Exhibit 99.1(a)

APPENDIX Share buy-back programme - Specification for April 14 – April 18, 2025

Issuer	Date	Time CET	Quantity	Price (DKK)	Venue
GENMAB A/S	14-Apr-2025	9:55:18 AM	78	1259.50	XCSE
GENMAB A/S	14-Apr-2025	9:55:30 AM	82	1259.00	CEUX
GENMAB A/S	14-Apr-2025	9:55:32 AM	86	1258.50	XCSE
GENMAB A/S	14-Apr-2025	9:56:01 AM	76	1258.00	TQEX
GENMAB A/S	14-Apr-2025	9:56:14 AM	74	1258.00	AQEU
GENMAB A/S	14-Apr-2025	9:56:31 AM	84	1257.50	XCSE
GENMAB A/S	14-Apr-2025	9:56:31 AM	77	1257.50	CEUX
GENMAB A/S	14-Apr-2025	9:56:32 AM	76	1257.00	TQEX
GENMAB A/S	14-Apr-2025	9:56:32 AM	77	1256.50	CEUX
GENMAB A/S	14-Apr-2025	9:56:32 AM	3	1256.50	CEUX
GENMAB A/S	14-Apr-2025	9:56:32 AM	87	1257.00	AQEU
GENMAB A/S	14-Apr-2025	9:56:33 AM	38	1256.00	XCSE
GENMAB A/S	14-Apr-2025	9:56:33 AM	81	1256.00	TQEX
GENMAB A/S	14-Apr-2025	9:56:33 AM	83	1256.00	AQEU
GENMAB A/S	14-Apr-2025	10:00:33 AM	22	1258.00	XCSE
GENMAB A/S	14-Apr-2025	10:00:33 AM	53	1258.00	XCSE
GENMAB A/S	14-Apr-2025	10:00:33 AM	12	1258.00	XCSE
GENMAB A/S	14-Apr-2025	10:00:33 AM	25	1258.00	CEUX
GENMAB A/S	14-Apr-2025	10:00:58 AM	18	1260.00	CEUX
GENMAB A/S	14-Apr-2025	10:02:01 AM	85	1261.00	XCSE
GENMAB A/S	14-Apr-2025	10:02:01 AM	31	1261.00	TQEX
GENMAB A/S	14-Apr-2025	10:02:01 AM	15	1261.00	CEUX
GENMAB A/S	14-Apr-2025	10:02:01 AM	32	1261.00	CEUX
GENMAB A/S	14-Apr-2025	10:04:31 AM	52	1261.00	CEUX
GENMAB A/S	14-Apr-2025	10:04:39 AM	31	1260.50	XCSE
GENMAB A/S	14-Apr-2025	10:04:39 AM	53	1260.50	XCSE
GENMAB A/S	14-Apr-2025	10:04:39 AM	25	1260.50	TQEX
GENMAB A/S	14-Apr-2025	10:04:39 AM	8	1260.00	CEUX
GENMAB A/S	14-Apr-2025	10:04:39 AM	5	1260.00	CEUX
GENMAB A/S	14-Apr-2025	10:04:39 AM	7	1260.00	CEUX
GENMAB A/S	14-Apr-2025	10:06:13 AM	60	1261.00	CEUX
GENMAB A/S	14-Apr-2025	10:06:45 AM	88	1260.50	XCSE
GENMAB A/S	14-Apr-2025	10:09:28 AM	83	1259.50	XCSE
GENMAB A/S	14-Apr-2025	10:09:28 AM	3	1259.50	XCSE
GENMAB A/S	14-Apr-2025	10:09:28 AM	16	1259.50	XCSE
GENMAB A/S	14-Apr-2025	10:09:28 AM	8	1259.50	XCSE
GENMAB A/S	14-Apr-2025	10:09:28 AM	13	1259.50	XCSE
GENMAB A/S	14-Apr-2025	10:09:28 AM	5	1259.50	XCSE
GENMAB A/S	14-Apr-2025	10:09:28 AM	5	1259.50	XCSE
GENMAB A/S	14-Apr-2025	10:09:28 AM	15	1259.50	XCSE
GENMAB A/S	14-Apr-2025	10:09:28 AM	8	1259.50	XCSE

Exhibit 99.1(a)

APPENDIX Share buy-back programme - Specification for April 14 – April 18, 2025

GENMAB A/S	14-Apr-2025	10:09:28 AM	30	1260.00	TQEX
GENMAB A/S	14-Apr-2025	10:09:28 AM	2	1259.00	TQEX
GENMAB A/S	14-Apr-2025	10:09:28 AM	5	1259.00	TQEX
GENMAB A/S	14-Apr-2025	10:09:28 AM	2	1259.00	TQEX
GENMAB A/S	14-Apr-2025	10:09:28 AM	7	1259.00	TQEX
GENMAB A/S	14-Apr-2025	10:09:28 AM	2	1259.00	TQEX
GENMAB A/S	14-Apr-2025	10:09:28 AM	6	1260.00	CEUX
GENMAB A/S	14-Apr-2025	10:09:28 AM	8	1259.00	CEUX
GENMAB A/S	14-Apr-2025	10:09:28 AM	2	1259.00	CEUX
GENMAB A/S	14-Apr-2025	10:09:28 AM	7	1259.00	CEUX
GENMAB A/S	14-Apr-2025	10:09:47 AM	39	1260.00	XCSE
GENMAB A/S	14-Apr-2025	10:09:56 AM	11	1260.00	XCSE
GENMAB A/S	14-Apr-2025	10:09:56 AM	10	1260.00	XCSE
GENMAB A/S	14-Apr-2025	10:09:56 AM	39	1260.00	XCSE
GENMAB A/S	14-Apr-2025	10:10:03 AM	39	1260.00	XCSE
GENMAB A/S	14-Apr-2025	10:10:30 AM	19	1260.00	XCSE
GENMAB A/S	14-Apr-2025	10:10:30 AM	39	1260.00	XCSE
GENMAB A/S	14-Apr-2025	10:10:58 AM	82	1259.50	XCSE
GENMAB A/S	14-Apr-2025	10:10:58 AM	50	1259.50	XCSE
GENMAB A/S	14-Apr-2025	10:10:58 AM	59	1259.50	XCSE
GENMAB A/S	14-Apr-2025	10:10:58 AM	3	1259.50	XCSE
GENMAB A/S	14-Apr-2025	10:10:58 AM	14	1259.00	CEUX
GENMAB A/S	14-Apr-2025	10:10:58 AM	29	1259.50	AQEU
GENMAB A/S	14-Apr-2025	10:11:00 AM	75	1258.50	XCSE
GENMAB A/S	14-Apr-2025	10:11:00 AM	13	1258.50	TQEX
GENMAB A/S	14-Apr-2025	10:11:00 AM	17	1258.50	TQEX
GENMAB A/S	14-Apr-2025	10:11:58 AM	9	1259.50	XCSE
GENMAB A/S	14-Apr-2025	10:11:58 AM	74	1259.50	XCSE
GENMAB A/S	14-Apr-2025	10:11:58 AM	84	1259.50	CEUX
GENMAB A/S	14-Apr-2025	10:12:17 AM	38	1260.00	XCSE
GENMAB A/S	14-Apr-2025	10:13:21 AM	21	1260.00	XCSE
GENMAB A/S	14-Apr-2025	10:13:21 AM	5	1260.00	XCSE
GENMAB A/S	14-Apr-2025	10:13:21 AM	48	1260.00	XCSE
GENMAB A/S	14-Apr-2025	10:13:21 AM	64	1260.00	XCSE
GENMAB A/S	14-Apr-2025	10:13:21 AM	27	1259.50	TQEX
GENMAB A/S	14-Apr-2025	10:13:21 AM	16	1260.00	CEUX
GENMAB A/S	14-Apr-2025	10:13:21 AM	11	1260.00	CEUX
GENMAB A/S	14-Apr-2025	10:13:21 AM	3	1260.00	CEUX
GENMAB A/S	14-Apr-2025	10:13:21 AM	24	1259.50	CEUX
GENMAB A/S	14-Apr-2025	10:13:21 AM	5	1259.50	CEUX
GENMAB A/S	14-Apr-2025	10:13:21 AM	10	1259.50	CEUX
GENMAB A/S	14-Apr-2025	10:13:21 AM	18	1259.50	CEUX
GENMAB A/S	14-Apr-2025	10:13:22 AM	76	1260.00	XCSE

Exhibit 99.1(a)

APPENDIX Share buy-back programme - Specification for April 14 – April 18, 2025

GENMAB A/S	14-Apr-2025	10:14:37 AM	6	1263.00	XCSE
GENMAB A/S	14-Apr-2025	10:14:48 AM	47	1263.50	XCSE
GENMAB A/S	14-Apr-2025	10:14:58 AM	84	1263.50	CEUX
GENMAB A/S	14-Apr-2025	10:15:05 AM	84	1263.00	XCSE
GENMAB A/S	14-Apr-2025	10:15:05 AM	24	1263.50	XCSE
GENMAB A/S	14-Apr-2025	10:15:05 AM	39	1263.50	XCSE
GENMAB A/S	14-Apr-2025	10:15:05 AM	36	1263.50	XCSE
GENMAB A/S	14-Apr-2025	10:15:05 AM	42	1263.00	XCSE
GENMAB A/S	14-Apr-2025	10:15:05 AM	32	1263.50	CEUX
GENMAB A/S	14-Apr-2025	10:15:05 AM	28	1263.00	AQEU
GENMAB A/S	14-Apr-2025	10:15:22 AM	87	1263.00	XCSE
GENMAB A/S	14-Apr-2025	10:15:22 AM	6	1263.00	CEUX
GENMAB A/S	14-Apr-2025	10:15:22 AM	9	1263.00	CEUX
GENMAB A/S	14-Apr-2025	10:15:22 AM	5	1263.00	CEUX
GENMAB A/S	14-Apr-2025	10:15:22 AM	5	1263.00	CEUX
GENMAB A/S	14-Apr-2025	10:15:22 AM	2	1262.50	CEUX
GENMAB A/S	14-Apr-2025	10:15:22 AM	1	1262.50	CEUX
GENMAB A/S	14-Apr-2025	10:15:22 AM	25	1262.50	CEUX
GENMAB A/S	14-Apr-2025	10:15:22 AM	3	1262.50	CEUX
GENMAB A/S	14-Apr-2025	10:15:22 AM	7	1262.50	CEUX
GENMAB A/S	14-Apr-2025	10:15:22 AM	8	1262.50	CEUX
GENMAB A/S	14-Apr-2025	10:15:22 AM	9	1262.50	CEUX
GENMAB A/S	14-Apr-2025	10:15:22 AM	5	1262.50	CEUX
GENMAB A/S	14-Apr-2025	10:15:22 AM	3	1262.50	CEUX
GENMAB A/S	14-Apr-2025	10:15:23 AM	20	1262.50	CEUX
GENMAB A/S	14-Apr-2025	10:19:02 AM	41	1265.50	XCSE
GENMAB A/S	14-Apr-2025	10:19:08 AM	41	1265.50	XCSE
GENMAB A/S	14-Apr-2025	10:21:37 AM	20	1265.00	XCSE
GENMAB A/S	14-Apr-2025	10:21:40 AM	28	1265.00	XCSE
GENMAB A/S	14-Apr-2025	10:21:40 AM	13	1265.00	XCSE
GENMAB A/S	14-Apr-2025	10:21:43 AM	28	1265.00	XCSE
GENMAB A/S	14-Apr-2025	10:21:43 AM	21	1265.00	XCSE
GENMAB A/S	14-Apr-2025	10:21:43 AM	14	1265.00	XCSE
GENMAB A/S	14-Apr-2025	10:21:56 AM	28	1265.00	XCSE
GENMAB A/S	14-Apr-2025	10:21:56 AM	28	1265.00	XCSE
GENMAB A/S	14-Apr-2025	10:21:58 AM	28	1265.00	XCSE
GENMAB A/S	14-Apr-2025	10:21:58 AM	28	1265.00	XCSE
GENMAB A/S	14-Apr-2025	10:21:58 AM	28	1265.00	XCSE
GENMAB A/S	14-Apr-2025	10:22:39 AM	11	1264.50	XCSE
GENMAB A/S	14-Apr-2025	10:22:39 AM	32	1265.00	TQEX
GENMAB A/S	14-Apr-2025	10:22:39 AM	49	1265.50	CEUX
GENMAB A/S	14-Apr-2025	10:23:28 AM	12	1265.00	TQEX
GENMAB A/S	14-Apr-2025	10:23:28 AM	23	1265.00	TQEX

Exhibit 99.1(a)

APPENDIX Share buy-back programme - Specification for April 14 – April 18, 2025

GENMAB A/S	14-Apr-2025	10:23:30 AM	36	1265.00	CEUX
GENMAB A/S	14-Apr-2025	10:23:30 AM	36	1265.00	CEUX
GENMAB A/S	14-Apr-2025	10:23:38 AM	46	1264.50	XCSE
GENMAB A/S	14-Apr-2025	10:23:38 AM	3	1264.50	XCSE
GENMAB A/S	14-Apr-2025	10:23:38 AM	29	1264.50	XCSE
GENMAB A/S	14-Apr-2025	10:23:38 AM	8	1264.00	XCSE
GENMAB A/S	14-Apr-2025	10:23:38 AM	5	1264.00	TQEX
GENMAB A/S	14-Apr-2025	10:23:38 AM	13	1264.00	TQEX
GENMAB A/S	14-Apr-2025	10:23:38 AM	9	1264.00	TQEX
GENMAB A/S	14-Apr-2025	10:23:38 AM	6	1264.50	CEUX
GENMAB A/S	14-Apr-2025	10:23:38 AM	3	1264.50	CEUX
GENMAB A/S	14-Apr-2025	10:23:38 AM	34	1264.50	CEUX
GENMAB A/S	14-Apr-2025	10:23:38 AM	44	1264.50	CEUX
GENMAB A/S	14-Apr-2025	10:23:38 AM	26	1264.50	CEUX
GENMAB A/S	14-Apr-2025	10:23:38 AM	9	1263.50	CEUX
GENMAB A/S	14-Apr-2025	10:23:38 AM	2	1263.50	CEUX
GENMAB A/S	14-Apr-2025	10:23:38 AM	3	1263.50	CEUX
GENMAB A/S	14-Apr-2025	10:23:38 AM	4	1263.50	CEUX
GENMAB A/S	14-Apr-2025	10:23:38 AM	43	1264.50	AQEU
GENMAB A/S	14-Apr-2025	10:24:37 AM	86	1264.50	CEUX
GENMAB A/S	14-Apr-2025	10:26:23 AM	76	1264.50	CEUX
GENMAB A/S	14-Apr-2025	10:26:29 AM	71	1265.00	XCSE
GENMAB A/S	14-Apr-2025	10:26:43 AM	24	1265.00	AQEU
GENMAB A/S	14-Apr-2025	10:28:29 AM	12	1265.00	XCSE
GENMAB A/S	14-Apr-2025	10:29:42 AM	36	1267.50	XCSE
GENMAB A/S	14-Apr-2025	10:29:43 AM	36	1267.50	XCSE
GENMAB A/S	14-Apr-2025	10:29:43 AM	5	1267.50	XCSE
GENMAB A/S	14-Apr-2025	10:30:37 AM	91	1268.00	XCSE
GENMAB A/S	14-Apr-2025	10:30:37 AM	21	1268.00	XCSE
GENMAB A/S	14-Apr-2025	10:30:38 AM	90	1268.00	XCSE
GENMAB A/S	14-Apr-2025	10:30:38 AM	22	1268.00	XCSE
GENMAB A/S	14-Apr-2025	10:30:38 AM	91	1268.00	XCSE
GENMAB A/S	14-Apr-2025	10:30:38 AM	21	1268.00	XCSE
GENMAB A/S	14-Apr-2025	10:30:47 AM	48	1269.50	XCSE
GENMAB A/S	14-Apr-2025	10:30:47 AM	32	1269.50	XCSE
GENMAB A/S	14-Apr-2025	10:30:47 AM	32	1269.50	XCSE
GENMAB A/S	14-Apr-2025	10:30:47 AM	4	1269.00	CEUX
GENMAB A/S	14-Apr-2025	10:30:48 AM	31	1269.50	CEUX
GENMAB A/S	14-Apr-2025	10:30:50 AM	112	1270.00	XCSE
GENMAB A/S	14-Apr-2025	10:31:14 AM	36	1272.00	CEUX
GENMAB A/S	14-Apr-2025	10:31:36 AM	34	1272.00	XCSE
GENMAB A/S	14-Apr-2025	10:32:02 AM	45	1272.50	CEUX
GENMAB A/S	14-Apr-2025	10:32:02 AM	41	1272.50	CEUX

Exhibit 99.1(a)

APPENDIX Share buy-back programme - Specification for April 14 – April 18, 2025

GENMAB A/S	14-Apr-2025	10:32:03 AM	82	1272.50	XCSE
GENMAB A/S	14-Apr-2025	10:32:03 AM	31	1272.50	XCSE
GENMAB A/S	14-Apr-2025	10:32:03 AM	19	1272.50	TQEX
GENMAB A/S	14-Apr-2025	10:32:03 AM	7	1272.50	TQEX
GENMAB A/S	14-Apr-2025	10:32:03 AM	40	1273.50	CEUX
GENMAB A/S	14-Apr-2025	10:32:03 AM	12	1273.50	CEUX
GENMAB A/S	14-Apr-2025	10:32:03 AM	42	1272.50	CEUX
GENMAB A/S	14-Apr-2025	10:32:03 AM	40	1272.50	CEUX
GENMAB A/S	14-Apr-2025	10:32:03 AM	38	1273.00	AQEU
GENMAB A/S	14-Apr-2025	10:32:04 AM	47	1272.50	XCSE
GENMAB A/S	14-Apr-2025	10:32:04 AM	31	1272.50	XCSE
GENMAB A/S	14-Apr-2025	10:32:04 AM	34	1272.50	XCSE
GENMAB A/S	14-Apr-2025	10:32:04 AM	31	1272.50	XCSE
GENMAB A/S	14-Apr-2025	10:32:04 AM	32	1272.50	CEUX
GENMAB A/S	14-Apr-2025	10:32:17 AM	31	1272.50	XCSE
GENMAB A/S	14-Apr-2025	10:32:17 AM	32	1272.50	CEUX
GENMAB A/S	14-Apr-2025	10:32:18 AM	4	1272.50	XCSE
GENMAB A/S	14-Apr-2025	10:32:30 AM	89	1272.50	XCSE
GENMAB A/S	14-Apr-2025	10:32:30 AM	39	1273.00	XCSE
GENMAB A/S	14-Apr-2025	10:32:30 AM	16	1273.00	XCSE
GENMAB A/S	14-Apr-2025	10:32:30 AM	30	1272.50	TQEX
GENMAB A/S	14-Apr-2025	10:32:30 AM	83	1272.50	CEUX
GENMAB A/S	14-Apr-2025	10:32:30 AM	11	1272.50	AQEU
GENMAB A/S	14-Apr-2025	10:32:30 AM	32	1272.50	AQEU
GENMAB A/S	14-Apr-2025	10:32:39 AM	84	1271.50	XCSE
GENMAB A/S	14-Apr-2025	10:32:39 AM	27	1271.50	TQEX
GENMAB A/S	14-Apr-2025	10:32:39 AM	28	1271.50	CEUX
GENMAB A/S	14-Apr-2025	10:32:39 AM	35	1271.50	CEUX
GENMAB A/S	14-Apr-2025	10:32:39 AM	26	1271.50	CEUX
GENMAB A/S	14-Apr-2025	10:32:39 AM	28	1271.50	AQEU
GENMAB A/S	14-Apr-2025	10:33:08 AM	83	1270.50	XCSE
GENMAB A/S	14-Apr-2025	10:33:08 AM	8	1270.50	CEUX
GENMAB A/S	14-Apr-2025	10:33:09 AM	78	1270.50	CEUX
GENMAB A/S	14-Apr-2025	10:33:26 AM	25	1270.00	AQEU
GENMAB A/S	14-Apr-2025	10:33:55 AM	82	1269.00	XCSE
GENMAB A/S	14-Apr-2025	10:34:14 AM	85	1269.00	CEUX
GENMAB A/S	14-Apr-2025	10:34:32 AM	7	1268.00	CEUX
GENMAB A/S	14-Apr-2025	10:37:22 AM	22	1270.00	XCSE
GENMAB A/S	14-Apr-2025	10:37:22 AM	90	1270.00	XCSE
GENMAB A/S	14-Apr-2025	10:37:23 AM	12	1270.00	CEUX
GENMAB A/S	14-Apr-2025	10:37:23 AM	24	1270.00	CEUX
GENMAB A/S	14-Apr-2025	10:37:24 AM	32	1270.00	CEUX
GENMAB A/S	14-Apr-2025	10:37:24 AM	12	1270.00	CEUX

Exhibit 99.1(a)

APPENDIX Share buy-back programme - Specification for April 14 – April 18, 2025

GENMAB A/S	14-Apr-2025	10:37:24 AM	3	1270.00	CEUX
GENMAB A/S	14-Apr-2025	10:37:40 AM	22	1270.00	XCSE
GENMAB A/S	14-Apr-2025	10:37:40 AM	3	1270.00	XCSE
GENMAB A/S	14-Apr-2025	10:38:10 AM	31	1271.00	XCSE
GENMAB A/S	14-Apr-2025	10:38:21 AM	13	1271.50	XCSE
GENMAB A/S	14-Apr-2025	10:38:21 AM	12	1271.50	XCSE
GENMAB A/S	14-Apr-2025	10:38:30 AM	85	1271.00	XCSE
GENMAB A/S	14-Apr-2025	10:38:32 AM	27	1270.50	TQEX
GENMAB A/S	14-Apr-2025	10:40:00 AM	47	1271.00	XCSE
GENMAB A/S	14-Apr-2025	10:40:00 AM	65	1271.00	XCSE
GENMAB A/S	14-Apr-2025	10:41:47 AM	39	1271.00	XCSE
GENMAB A/S	14-Apr-2025	10:41:47 AM	35	1271.00	XCSE
GENMAB A/S	14-Apr-2025	10:41:47 AM	11	1271.00	XCSE
GENMAB A/S	14-Apr-2025	10:41:47 AM	27	1271.00	XCSE
GENMAB A/S	14-Apr-2025	10:41:47 AM	1	1271.00	TQEX
GENMAB A/S	14-Apr-2025	10:41:47 AM	24	1271.00	TQEX
GENMAB A/S	14-Apr-2025	10:41:47 AM	3	1271.00	CEUX
GENMAB A/S	14-Apr-2025	10:41:47 AM	84	1271.00	CEUX
GENMAB A/S	14-Apr-2025	10:42:33 AM	83	1270.00	XCSE
GENMAB A/S	14-Apr-2025	10:42:33 AM	35	1270.00	XCSE
GENMAB A/S	14-Apr-2025	10:42:33 AM	82	1270.00	CEUX
GENMAB A/S	14-Apr-2025	10:42:33 AM	33	1270.00	AQEU
GENMAB A/S	14-Apr-2025	10:42:45 AM	17	1269.50	TQEX
GENMAB A/S	14-Apr-2025	10:43:07 AM	83	1269.00	CEUX
GENMAB A/S	14-Apr-2025	10:43:07 AM	27	1269.00	AQEU
GENMAB A/S	14-Apr-2025	10:43:07 AM	5	1269.00	AQEU
GENMAB A/S	14-Apr-2025	10:43:15 AM	58	1268.50	XCSE
GENMAB A/S	14-Apr-2025	10:43:15 AM	24	1268.50	XCSE
GENMAB A/S	14-Apr-2025	10:45:42 AM	10	1268.50	XCSE
GENMAB A/S	14-Apr-2025	10:46:59 AM	64	1268.50	XCSE
GENMAB A/S	14-Apr-2025	10:46:59 AM	20	1268.50	XCSE
GENMAB A/S	14-Apr-2025	10:46:59 AM	35	1268.50	XCSE
GENMAB A/S	14-Apr-2025	10:46:59 AM	26	1268.50	XCSE
GENMAB A/S	14-Apr-2025	10:46:59 AM	83	1268.50	CEUX
GENMAB A/S	14-Apr-2025	10:47:10 AM	26	1268.50	XCSE
GENMAB A/S	14-Apr-2025	10:47:10 AM	35	1268.50	XCSE
GENMAB A/S	14-Apr-2025	10:47:21 AM	28	1268.00	TQEX
GENMAB A/S	14-Apr-2025	10:49:09 AM	59	1268.50	XCSE
GENMAB A/S	14-Apr-2025	10:49:23 AM	21	1268.50	XCSE
GENMAB A/S	14-Apr-2025	10:49:34 AM	37	1269.50	XCSE
GENMAB A/S	14-Apr-2025	10:49:34 AM	26	1269.50	XCSE
GENMAB A/S	14-Apr-2025	10:49:34 AM	16	1269.50	XCSE
GENMAB A/S	14-Apr-2025	10:49:34 AM	33	1269.50	XCSE

Exhibit 99.1(a)

APPENDIX Share buy-back programme - Specification for April 14 – April 18, 2025

GENMAB A/S	14-Apr-2025	10:50:10 AM	11	1269.50	XCSE
GENMAB A/S	14-Apr-2025	10:50:10 AM	39	1269.50	XCSE
GENMAB A/S	14-Apr-2025	10:50:10 AM	23	1269.50	XCSE
GENMAB A/S	14-Apr-2025	10:50:40 AM	45	1269.00	XCSE
GENMAB A/S	14-Apr-2025	10:51:05 AM	3	1268.50	XCSE
GENMAB A/S	14-Apr-2025	10:51:05 AM	28	1268.50	TQEX
GENMAB A/S	14-Apr-2025	10:51:05 AM	86	1268.50	CEUX
GENMAB A/S	14-Apr-2025	10:51:05 AM	37	1268.50	AQEU
GENMAB A/S	14-Apr-2025	10:51:13 AM	83	1267.50	XCSE
GENMAB A/S	14-Apr-2025	10:51:13 AM	89	1267.50	CEUX
GENMAB A/S	14-Apr-2025	10:51:13 AM	34	1267.50	AQEU
GENMAB A/S	14-Apr-2025	10:53:59 AM	73	1267.50	XCSE
GENMAB A/S	14-Apr-2025	10:54:34 AM	89	1268.50	XCSE
GENMAB A/S	14-Apr-2025	10:54:34 AM	27	1268.50	TQEX
GENMAB A/S	14-Apr-2025	10:54:34 AM	89	1268.50	CEUX
GENMAB A/S	14-Apr-2025	10:54:34 AM	36	1268.50	AQEU
GENMAB A/S	14-Apr-2025	10:54:40 AM	35	1268.50	XCSE
GENMAB A/S	14-Apr-2025	10:54:40 AM	26	1268.50	XCSE
GENMAB A/S	14-Apr-2025	10:54:40 AM	10	1268.50	XCSE
GENMAB A/S	14-Apr-2025	10:56:09 AM	44	1268.50	XCSE
GENMAB A/S	14-Apr-2025	10:56:09 AM	42	1268.50	XCSE
GENMAB A/S	14-Apr-2025	10:56:09 AM	82	1268.50	CEUX
GENMAB A/S	14-Apr-2025	10:56:14 AM	25	1268.50	TQEX
GENMAB A/S	14-Apr-2025	10:56:29 AM	32	1268.00	AQEU
GENMAB A/S	14-Apr-2025	10:56:40 AM	48	1268.50	XCSE
GENMAB A/S	14-Apr-2025	10:56:40 AM	32	1268.50	XCSE
GENMAB A/S	14-Apr-2025	10:56:40 AM	21	1268.50	XCSE
GENMAB A/S	14-Apr-2025	10:56:40 AM	11	1268.50	XCSE
GENMAB A/S	14-Apr-2025	10:59:24 AM	84	1269.50	XCSE
GENMAB A/S	14-Apr-2025	10:59:30 AM	34	1269.50	XCSE
GENMAB A/S	14-Apr-2025	11:00:23 AM	31	1269.50	XCSE
GENMAB A/S	14-Apr-2025	11:00:23 AM	9	1270.00	CEUX
GENMAB A/S	14-Apr-2025	11:01:00 AM	12	1270.50	XCSE
GENMAB A/S	14-Apr-2025	11:01:00 AM	100	1270.50	XCSE
GENMAB A/S	14-Apr-2025	11:01:02 AM	36	1270.50	XCSE
GENMAB A/S	14-Apr-2025	11:01:34 AM	75	1271.50	XCSE
GENMAB A/S	14-Apr-2025	11:01:34 AM	5	1271.50	CEUX
GENMAB A/S	14-Apr-2025	11:03:43 AM	88	1272.50	XCSE
GENMAB A/S	14-Apr-2025	11:03:43 AM	27	1272.50	TQEX
GENMAB A/S	14-Apr-2025	11:03:43 AM	39	1272.50	CEUX
GENMAB A/S	14-Apr-2025	11:03:43 AM	47	1272.50	CEUX
GENMAB A/S	14-Apr-2025	11:03:43 AM	20	1272.50	CEUX
GENMAB A/S	14-Apr-2025	11:04:42 AM	5	1272.50	XCSE

Exhibit 99.1(a)

APPENDIX Share buy-back programme - Specification for April 14 – April 18, 2025

GENMAB A/S	14-Apr-2025	11:04:42 AM	89	1273.00	CEUX
GENMAB A/S	14-Apr-2025	11:04:42 AM	28	1273.00	AQEU
GENMAB A/S	14-Apr-2025	11:05:41 AM	35	1273.00	XCSE
GENMAB A/S	14-Apr-2025	11:05:41 AM	13	1273.00	XCSE
GENMAB A/S	14-Apr-2025	11:05:41 AM	41	1273.00	XCSE
GENMAB A/S	14-Apr-2025	11:05:41 AM	84	1272.50	XCSE
GENMAB A/S	14-Apr-2025	11:05:41 AM	25	1272.50	TQEX
GENMAB A/S	14-Apr-2025	11:05:41 AM	5	1273.00	CEUX
GENMAB A/S	14-Apr-2025	11:05:41 AM	5	1273.00	CEUX
GENMAB A/S	14-Apr-2025	11:05:41 AM	32	1272.50	CEUX
GENMAB A/S	14-Apr-2025	11:05:45 AM	32	1272.50	CEUX
GENMAB A/S	14-Apr-2025	11:06:34 AM	46	1272.50	XCSE
GENMAB A/S	14-Apr-2025	11:06:34 AM	26	1272.50	XCSE
GENMAB A/S	14-Apr-2025	11:06:39 AM	13	1272.50	XCSE
GENMAB A/S	14-Apr-2025	11:06:39 AM	26	1272.50	CEUX
GENMAB A/S	14-Apr-2025	11:06:40 AM	13	1272.50	XCSE
GENMAB A/S	14-Apr-2025	11:07:03 AM	29	1272.50	XCSE
GENMAB A/S	14-Apr-2025	11:07:03 AM	4	1271.50	XCSE
GENMAB A/S	14-Apr-2025	11:07:03 AM	82	1271.50	XCSE
GENMAB A/S	14-Apr-2025	11:07:03 AM	26	1271.50	TQEX
GENMAB A/S	14-Apr-2025	11:07:03 AM	5	1272.50	CEUX
GENMAB A/S	14-Apr-2025	11:07:03 AM	5	1272.50	CEUX
GENMAB A/S	14-Apr-2025	11:07:03 AM	87	1272.00	CEUX
GENMAB A/S	14-Apr-2025	11:07:03 AM	7	1271.00	CEUX
GENMAB A/S	14-Apr-2025	11:07:03 AM	2	1271.00	CEUX
GENMAB A/S	14-Apr-2025	11:07:03 AM	45	1271.00	CEUX
GENMAB A/S	14-Apr-2025	11:07:03 AM	24	1271.00	CEUX
GENMAB A/S	14-Apr-2025	11:07:03 AM	5	1271.00	CEUX
GENMAB A/S	14-Apr-2025	11:07:03 AM	28	1272.00	AQEU
GENMAB A/S	14-Apr-2025	11:08:27 AM	36	1272.50	XCSE
GENMAB A/S	14-Apr-2025	11:10:26 AM	39	1272.00	XCSE
GENMAB A/S	14-Apr-2025	11:10:26 AM	28	1272.50	XCSE
GENMAB A/S	14-Apr-2025	11:10:26 AM	11	1272.50	XCSE
GENMAB A/S	14-Apr-2025	11:10:26 AM	34	1272.50	XCSE
GENMAB A/S	14-Apr-2025	11:10:26 AM	25	1272.00	TQEX
GENMAB A/S	14-Apr-2025	11:10:26 AM	87	1272.00	CEUX
GENMAB A/S	14-Apr-2025	11:10:30 AM	43	1272.50	XCSE
GENMAB A/S	14-Apr-2025	11:10:40 AM	5	1272.50	XCSE
GENMAB A/S	14-Apr-2025	11:11:16 AM	21	1273.00	CEUX
GENMAB A/S	14-Apr-2025	11:11:20 AM	62	1273.00	CEUX
GENMAB A/S	14-Apr-2025	11:12:10 AM	35	1272.50	XCSE
GENMAB A/S	14-Apr-2025	11:12:10 AM	53	1272.50	XCSE
GENMAB A/S	14-Apr-2025	11:12:10 AM	25	1272.50	TQEX

Exhibit 99.1(a)

APPENDIX Share buy-back programme - Specification for April 14 – April 18, 2025

GENMAB A/S	14-Apr-2025	11:12:10 AM	25	1272.50	AQEU
GENMAB A/S	14-Apr-2025	11:14:42 AM	55	1272.50	XCSE
GENMAB A/S	14-Apr-2025	11:14:42 AM	12	1272.50	XCSE
GENMAB A/S	14-Apr-2025	11:14:42 AM	17	1272.50	XCSE
GENMAB A/S	14-Apr-2025	11:14:42 AM	28	1272.50	XCSE
GENMAB A/S	14-Apr-2025	11:15:55 AM	39	1274.00	CEUX
GENMAB A/S	14-Apr-2025	11:15:55 AM	28	1274.00	CEUX
GENMAB A/S	14-Apr-2025	11:16:12 AM	33	1274.00	XCSE
GENMAB A/S	14-Apr-2025	11:16:12 AM	15	1274.00	XCSE
GENMAB A/S	14-Apr-2025	11:16:12 AM	39	1274.00	XCSE
GENMAB A/S	14-Apr-2025	11:16:13 AM	49	1274.00	XCSE
GENMAB A/S	14-Apr-2025	11:17:02 AM	85	1273.50	XCSE
GENMAB A/S	14-Apr-2025	11:17:48 AM	32	1274.00	CEUX
GENMAB A/S	14-Apr-2025	11:18:16 AM	15	1273.50	TQEX
GENMAB A/S	14-Apr-2025	11:18:16 AM	46	1273.50	CEUX
GENMAB A/S	14-Apr-2025	11:18:16 AM	27	1273.50	CEUX
GENMAB A/S	14-Apr-2025	11:18:16 AM	12	1273.50	CEUX
GENMAB A/S	14-Apr-2025	11:18:17 AM	10	1273.50	TQEX
GENMAB A/S	14-Apr-2025	11:18:29 AM	39	1273.50	XCSE
GENMAB A/S	14-Apr-2025	11:18:29 AM	26	1273.50	XCSE
GENMAB A/S	14-Apr-2025	11:18:29 AM	21	1273.50	AQEU
GENMAB A/S	14-Apr-2025	11:18:29 AM	12	1273.50	AQEU
GENMAB A/S	14-Apr-2025	11:19:49 AM	55	1272.50	XCSE
GENMAB A/S	14-Apr-2025	11:20:18 AM	32	1272.50	XCSE
GENMAB A/S	14-Apr-2025	11:20:18 AM	13	1272.50	XCSE
GENMAB A/S	14-Apr-2025	11:20:18 AM	12	1272.50	XCSE
GENMAB A/S	14-Apr-2025	11:20:18 AM	26	1272.50	TQEX
GENMAB A/S	14-Apr-2025	11:20:18 AM	25	1272.50	AQEU
GENMAB A/S	14-Apr-2025	11:20:20 AM	58	1272.50	XCSE
GENMAB A/S	14-Apr-2025	11:20:20 AM	11	1272.50	XCSE
GENMAB A/S	14-Apr-2025	11:20:20 AM	82	1272.00	CEUX
GENMAB A/S	14-Apr-2025	11:20:23 AM	3	1272.50	XCSE
GENMAB A/S	14-Apr-2025	11:20:25 AM	88	1271.50	XCSE
GENMAB A/S	14-Apr-2025	11:20:25 AM	50	1272.00	XCSE
GENMAB A/S	14-Apr-2025	11:20:25 AM	3	1272.00	XCSE
GENMAB A/S	14-Apr-2025	11:20:25 AM	58	1272.00	XCSE
GENMAB A/S	14-Apr-2025	11:20:25 AM	1	1272.50	XCSE
GENMAB A/S	14-Apr-2025	11:20:25 AM	47	1272.00	CEUX
GENMAB A/S	14-Apr-2025	11:20:25 AM	42	1272.00	CEUX
GENMAB A/S	14-Apr-2025	11:21:29 AM	31	1271.50	AQEU
GENMAB A/S	14-Apr-2025	11:22:17 AM	88	1271.50	XCSE
GENMAB A/S	14-Apr-2025	11:22:17 AM	25	1271.50	XCSE
GENMAB A/S	14-Apr-2025	11:22:17 AM	25	1271.50	TQEX

Exhibit 99.1(a)

APPENDIX Share buy-back programme - Specification for April 14 – April 18, 2025

GENMAB A/S	14-Apr-2025	11:23:09 AM	82	1271.00	CEUX
GENMAB A/S	14-Apr-2025	11:23:31 AM	38	1270.50	XCSE
GENMAB A/S	14-Apr-2025	11:23:31 AM	87	1270.00	XCSE
GENMAB A/S	14-Apr-2025	11:23:50 AM	35	1270.00	XCSE
GENMAB A/S	14-Apr-2025	11:24:18 AM	48	1270.00	XCSE
GENMAB A/S	14-Apr-2025	11:24:18 AM	34	1270.00	AQEU
GENMAB A/S	14-Apr-2025	11:26:33 AM	35	1270.00	XCSE
GENMAB A/S	14-Apr-2025	11:26:33 AM	13	1270.00	XCSE
GENMAB A/S	14-Apr-2025	11:26:33 AM	47	1270.00	XCSE
GENMAB A/S	14-Apr-2025	11:26:33 AM	75	1269.50	CEUX
GENMAB A/S	14-Apr-2025	11:26:33 AM	10	1269.50	CEUX
GENMAB A/S	14-Apr-2025	11:29:38 AM	89	1271.50	XCSE
GENMAB A/S	14-Apr-2025	11:29:38 AM	58	1271.50	XCSE
GENMAB A/S	14-Apr-2025	11:29:38 AM	13	1271.50	XCSE
GENMAB A/S	14-Apr-2025	11:29:38 AM	25	1271.50	TQEX
GENMAB A/S	14-Apr-2025	11:29:38 AM	85	1271.50	CEUX
GENMAB A/S	14-Apr-2025	11:29:53 AM	10	1271.50	XCSE
GENMAB A/S	14-Apr-2025	11:29:53 AM	21	1271.50	XCSE
GENMAB A/S	14-Apr-2025	11:30:48 AM	22	1272.00	AQEU
GENMAB A/S	14-Apr-2025	11:31:44 AM	84	1273.50	CEUX
GENMAB A/S	14-Apr-2025	11:31:45 AM	51	1274.00	XCSE
GENMAB A/S	14-Apr-2025	11:31:45 AM	47	1274.00	XCSE
GENMAB A/S	14-Apr-2025	11:31:45 AM	14	1274.00	XCSE
GENMAB A/S	14-Apr-2025	11:31:45 AM	76	1273.50	CEUX
GENMAB A/S	14-Apr-2025	11:31:45 AM	6	1273.50	CEUX
GENMAB A/S	14-Apr-2025	11:32:10 AM	10	1274.00	XCSE
GENMAB A/S	14-Apr-2025	11:32:10 AM	58	1274.00	XCSE
GENMAB A/S	14-Apr-2025	11:32:10 AM	44	1274.00	XCSE
GENMAB A/S	14-Apr-2025	11:32:57 AM	85	1274.00	XCSE
GENMAB A/S	14-Apr-2025	11:32:57 AM	25	1274.00	AQEU
GENMAB A/S	14-Apr-2025	11:32:57 AM	25	1274.50	TQEX
GENMAB A/S	14-Apr-2025	11:32:57 AM	83	1274.50	CEUX
GENMAB A/S	14-Apr-2025	11:35:50 AM	13	1273.50	CEUX
GENMAB A/S	14-Apr-2025	11:36:59 AM	84	1273.00	XCSE
GENMAB A/S	14-Apr-2025	11:36:59 AM	68	1273.00	XCSE
GENMAB A/S	14-Apr-2025	11:36:59 AM	15	1273.00	XCSE
GENMAB A/S	14-Apr-2025	11:36:59 AM	25	1273.50	TQEX
GENMAB A/S	14-Apr-2025	11:36:59 AM	75	1273.50	CEUX
GENMAB A/S	14-Apr-2025	11:37:00 AM	31	1273.00	XCSE
GENMAB A/S	14-Apr-2025	11:37:00 AM	11	1273.00	XCSE
GENMAB A/S	14-Apr-2025	11:37:13 AM	35	1272.50	CEUX
GENMAB A/S	14-Apr-2025	11:37:24 AM	27	1273.00	XCSE
GENMAB A/S	14-Apr-2025	11:37:26 AM	35	1273.00	XCSE

Exhibit 99.1(a)

APPENDIX Share buy-back programme - Specification for April 14 – April 18, 2025

GENMAB A/S	14-Apr-2025	11:37:26 AM	21	1273.00	XCSE
GENMAB A/S	14-Apr-2025	11:39:00 AM	31	1273.00	XCSE
GENMAB A/S	14-Apr-2025	11:39:00 AM	29	1272.50	AQEU
GENMAB A/S	14-Apr-2025	11:39:00 AM	26	1272.50	TQEX
GENMAB A/S	14-Apr-2025	11:39:00 AM	45	1272.50	CEUX
GENMAB A/S	14-Apr-2025	11:39:00 AM	3	1272.50	CEUX
GENMAB A/S	14-Apr-2025	11:39:30 AM	50	1272.50	XCSE
GENMAB A/S	14-Apr-2025	11:39:30 AM	58	1272.50	XCSE
GENMAB A/S	14-Apr-2025	11:39:49 AM	25	1272.00	CEUX
GENMAB A/S	14-Apr-2025	11:39:49 AM	1	1272.00	CEUX
GENMAB A/S	14-Apr-2025	11:40:43 AM	50	1272.50	XCSE
GENMAB A/S	14-Apr-2025	11:40:43 AM	12	1272.50	XCSE
GENMAB A/S	14-Apr-2025	11:41:29 AM	84	1273.50	XCSE
GENMAB A/S	14-Apr-2025	11:42:50 AM	37	1274.50	XCSE
GENMAB A/S	14-Apr-2025	11:43:30 AM	5	1274.50	XCSE
GENMAB A/S	14-Apr-2025	11:43:55 AM	44	1275.50	XCSE
GENMAB A/S	14-Apr-2025	11:44:20 AM	83	1275.50	XCSE
GENMAB A/S	14-Apr-2025	11:44:20 AM	25	1275.50	TQEX
GENMAB A/S	14-Apr-2025	11:45:17 AM	15	1275.50	CEUX
GENMAB A/S	14-Apr-2025	11:45:48 AM	39	1275.50	XCSE
GENMAB A/S	14-Apr-2025	11:46:19 AM	38	1275.50	XCSE
GENMAB A/S	14-Apr-2025	11:46:19 AM	55	1275.00	CEUX
GENMAB A/S	14-Apr-2025	11:46:19 AM	32	1275.00	CEUX
GENMAB A/S	14-Apr-2025	11:46:24 AM	26	1275.00	AQEU
GENMAB A/S	14-Apr-2025	11:46:30 AM	47	1275.00	XCSE
GENMAB A/S	14-Apr-2025	11:46:30 AM	35	1275.00	XCSE
GENMAB A/S	14-Apr-2025	11:46:30 AM	11	1275.00	XCSE
GENMAB A/S	14-Apr-2025	11:46:30 AM	49	1274.50	XCSE
GENMAB A/S	14-Apr-2025	11:46:30 AM	36	1274.50	XCSE
GENMAB A/S	14-Apr-2025	11:46:30 AM	10	1274.00	CEUX
GENMAB A/S	14-Apr-2025	11:46:30 AM	2	1274.00	CEUX
GENMAB A/S	14-Apr-2025	11:47:37 AM	32	1274.50	CEUX
GENMAB A/S	14-Apr-2025	11:47:37 AM	25	1274.50	CEUX
GENMAB A/S	14-Apr-2025	11:48:01 AM	82	1273.50	XCSE
GENMAB A/S	14-Apr-2025	11:48:01 AM	26	1274.00	AQEU
GENMAB A/S	14-Apr-2025	11:48:01 AM	74	1274.00	CEUX
GENMAB A/S	14-Apr-2025	11:49:01 AM	24	1273.00	AQEU
GENMAB A/S	14-Apr-2025	11:49:01 AM	25	1273.00	TQEX
GENMAB A/S	14-Apr-2025	11:49:01 AM	86	1273.00	CEUX
GENMAB A/S	14-Apr-2025	11:50:09 AM	66	1272.00	XCSE
GENMAB A/S	14-Apr-2025	11:51:43 AM	9	1273.00	XCSE
GENMAB A/S	14-Apr-2025	11:54:34 AM	25	1272.50	TQEX
GENMAB A/S	14-Apr-2025	11:54:44 AM	22	1272.50	AQEU

Exhibit 99.1(a)

APPENDIX Share buy-back programme - Specification for April 14 – April 18, 2025

GENMAB A/S	14-Apr-2025	11:55:19 AM	16	1272.00	XCSE
GENMAB A/S	14-Apr-2025	11:55:57 AM	36	1272.50	CEUX
GENMAB A/S	14-Apr-2025	11:56:20 AM	29	1273.00	XCSE
GENMAB A/S	14-Apr-2025	11:56:20 AM	27	1273.00	XCSE
GENMAB A/S	14-Apr-2025	11:56:20 AM	11	1273.00	XCSE
GENMAB A/S	14-Apr-2025	11:56:20 AM	11	1273.00	XCSE
GENMAB A/S	14-Apr-2025	11:56:21 AM	10	1273.00	XCSE
GENMAB A/S	14-Apr-2025	11:56:21 AM	1	1273.00	CEUX
GENMAB A/S	14-Apr-2025	11:58:08 AM	42	1273.00	XCSE
GENMAB A/S	14-Apr-2025	11:58:08 AM	50	1273.00	XCSE
GENMAB A/S	14-Apr-2025	11:58:08 AM	42	1273.00	XCSE
GENMAB A/S	14-Apr-2025	11:58:08 AM	11	1273.00	XCSE
GENMAB A/S	14-Apr-2025	11:58:08 AM	6	1273.00	CEUX
GENMAB A/S	14-Apr-2025	11:59:13 AM	8	1273.50	XCSE
GENMAB A/S	14-Apr-2025	11:59:13 AM	10	1273.50	XCSE
GENMAB A/S	14-Apr-2025	11:59:13 AM	35	1273.50	XCSE
GENMAB A/S	14-Apr-2025	11:59:13 AM	43	1273.50	XCSE
GENMAB A/S	14-Apr-2025	11:59:13 AM	15	1273.50	XCSE
GENMAB A/S	14-Apr-2025	11:59:13 AM	1	1273.50	XCSE
GENMAB A/S	14-Apr-2025	11:59:13 AM	62	1273.50	XCSE
GENMAB A/S	14-Apr-2025	11:59:13 AM	13	1273.50	XCSE
GENMAB A/S	14-Apr-2025	11:59:13 AM	37	1273.50	XCSE
GENMAB A/S	14-Apr-2025	11:59:14 AM	6	1273.50	XCSE
GENMAB A/S	14-Apr-2025	11:59:14 AM	12	1273.50	XCSE
GENMAB A/S	14-Apr-2025	11:59:14 AM	12	1273.50	XCSE
GENMAB A/S	14-Apr-2025	11:59:20 AM	10	1273.50	XCSE
GENMAB A/S	14-Apr-2025	11:59:20 AM	87	1273.00	CEUX
GENMAB A/S	14-Apr-2025	11:59:21 AM	38	1273.50	XCSE
GENMAB A/S	14-Apr-2025	11:59:51 AM	36	1274.00	CEUX
GENMAB A/S	14-Apr-2025	12:01:10 PM	84	1274.00	XCSE
GENMAB A/S	14-Apr-2025	12:01:10 PM	36	1274.50	CEUX
GENMAB A/S	14-Apr-2025	12:01:43 PM	47	1274.00	XCSE
GENMAB A/S	14-Apr-2025	12:01:43 PM	58	1274.00	XCSE
GENMAB A/S	14-Apr-2025	12:01:43 PM	7	1274.00	XCSE
GENMAB A/S	14-Apr-2025	12:01:43 PM	29	1274.00	AQEU
GENMAB A/S	14-Apr-2025	12:01:43 PM	35	1274.00	TQEX
GENMAB A/S	14-Apr-2025	12:01:44 PM	3	1274.00	CEUX
GENMAB A/S	14-Apr-2025	12:02:59 PM	33	1275.00	XCSE
GENMAB A/S	14-Apr-2025	12:02:59 PM	37	1275.00	XCSE
GENMAB A/S	14-Apr-2025	12:02:59 PM	2	1275.00	XCSE
GENMAB A/S	14-Apr-2025	12:04:04 PM	76	1276.00	XCSE
GENMAB A/S	14-Apr-2025	12:04:04 PM	8	1276.00	CEUX
GENMAB A/S	14-Apr-2025	12:04:04 PM	32	1276.00	CEUX

Exhibit 99.1(a)

APPENDIX Share buy-back programme - Specification for April 14 – April 18, 2025

GENMAB A/S	14-Apr-2025	12:04:04 PM	1	1276.00	CEUX
GENMAB A/S	14-Apr-2025	12:04:20 PM	74	1275.50	XCSE
GENMAB A/S	14-Apr-2025	12:04:20 PM	15	1275.50	XCSE
GENMAB A/S	14-Apr-2025	12:04:20 PM	36	1276.00	CEUX
GENMAB A/S	14-Apr-2025	12:04:20 PM	4	1276.00	CEUX
GENMAB A/S	14-Apr-2025	12:04:25 PM	36	1276.00	CEUX
GENMAB A/S	14-Apr-2025	12:05:01 PM	14	1276.00	CEUX
GENMAB A/S	14-Apr-2025	12:05:05 PM	39	1276.00	CEUX
GENMAB A/S	14-Apr-2025	12:05:27 PM	6	1276.00	CEUX
GENMAB A/S	14-Apr-2025	12:05:45 PM	5	1276.00	CEUX
GENMAB A/S	14-Apr-2025	12:05:45 PM	6	1276.00	CEUX
GENMAB A/S	14-Apr-2025	12:06:19 PM	6	1276.00	CEUX
GENMAB A/S	14-Apr-2025	12:06:19 PM	6	1276.00	CEUX
GENMAB A/S	14-Apr-2025	12:06:19 PM	36	1276.00	CEUX
GENMAB A/S	14-Apr-2025	12:06:30 PM	46	1275.00	XCSE
GENMAB A/S	14-Apr-2025	12:06:37 PM	18	1275.50	CEUX
GENMAB A/S	14-Apr-2025	12:06:38 PM	42	1275.50	XCSE
GENMAB A/S	14-Apr-2025	12:07:16 PM	25	1275.50	XCSE
GENMAB A/S	14-Apr-2025	12:08:11 PM	28	1275.50	XCSE
GENMAB A/S	14-Apr-2025	12:08:43 PM	83	1275.00	CEUX
GENMAB A/S	14-Apr-2025	12:09:01 PM	40	1275.50	XCSE
GENMAB A/S	14-Apr-2025	12:10:39 PM	63	1275.50	XCSE
GENMAB A/S	14-Apr-2025	12:10:41 PM	20	1275.50	XCSE
GENMAB A/S	14-Apr-2025	12:10:41 PM	6	1276.00	CEUX
GENMAB A/S	14-Apr-2025	12:11:05 PM	6	1276.00	CEUX
GENMAB A/S	14-Apr-2025	12:13:03 PM	15	1276.50	CEUX
GENMAB A/S	14-Apr-2025	12:13:13 PM	82	1276.50	CEUX
GENMAB A/S	14-Apr-2025	12:13:55 PM	48	1277.00	XCSE
GENMAB A/S	14-Apr-2025	12:14:27 PM	10	1277.00	XCSE
GENMAB A/S	14-Apr-2025	12:14:27 PM	23	1277.00	XCSE
GENMAB A/S	14-Apr-2025	12:16:12 PM	45	1277.00	XCSE
GENMAB A/S	14-Apr-2025	12:16:19 PM	78	1276.00	XCSE
GENMAB A/S	14-Apr-2025	12:16:19 PM	45	1276.50	AQEU
GENMAB A/S	14-Apr-2025	12:16:19 PM	3	1276.50	CEUX
GENMAB A/S	14-Apr-2025	12:17:07 PM	8	1276.00	XCSE
GENMAB A/S	14-Apr-2025	12:17:07 PM	2	1276.00	TQEX
GENMAB A/S	14-Apr-2025	12:17:07 PM	44	1276.00	TQEX
GENMAB A/S	14-Apr-2025	12:17:08 PM	44	1276.00	XCSE
GENMAB A/S	14-Apr-2025	12:17:08 PM	13	1276.00	XCSE
GENMAB A/S	14-Apr-2025	12:17:08 PM	44	1276.00	XCSE
GENMAB A/S	14-Apr-2025	12:17:09 PM	99	1276.00	XCSE
GENMAB A/S	14-Apr-2025	12:17:09 PM	13	1276.00	XCSE
GENMAB A/S	14-Apr-2025	12:17:09 PM	99	1276.00	XCSE

Exhibit 99.1(a)

APPENDIX Share buy-back programme - Specification for April 14 – April 18, 2025

GENMAB A/S	14-Apr-2025	12:17:09 PM	13	1276.00	XCSE
GENMAB A/S	14-Apr-2025	12:17:09 PM	1	1276.00	CEUX
GENMAB A/S	14-Apr-2025	12:19:43 PM	44	1276.50	CEUX
GENMAB A/S	14-Apr-2025	12:20:44 PM	49	1276.50	XCSE
GENMAB A/S	14-Apr-2025	12:20:44 PM	40	1276.50	CEUX
GENMAB A/S	14-Apr-2025	12:21:49 PM	36	1276.00	XCSE
GENMAB A/S	14-Apr-2025	12:21:49 PM	39	1276.00	AQEU
GENMAB A/S	14-Apr-2025	12:21:49 PM	15	1276.00	CEUX
GENMAB A/S	14-Apr-2025	12:21:49 PM	86	1275.50	CEUX
GENMAB A/S	14-Apr-2025	12:21:51 PM	36	1276.00	XCSE
GENMAB A/S	14-Apr-2025	12:21:53 PM	36	1276.00	XCSE
GENMAB A/S	14-Apr-2025	12:21:53 PM	23	1276.00	XCSE
GENMAB A/S	14-Apr-2025	12:21:53 PM	13	1276.00	XCSE
GENMAB A/S	14-Apr-2025	12:21:53 PM	35	1276.00	XCSE
GENMAB A/S	14-Apr-2025	12:21:53 PM	10	1276.00	XCSE
GENMAB A/S	14-Apr-2025	12:21:53 PM	31	1276.00	XCSE
GENMAB A/S	14-Apr-2025	12:21:53 PM	11	1276.00	XCSE
GENMAB A/S	14-Apr-2025	12:21:53 PM	11	1276.00	XCSE
GENMAB A/S	14-Apr-2025	12:21:53 PM	43	1276.00	XCSE
GENMAB A/S	14-Apr-2025	12:21:53 PM	36	1276.00	XCSE
GENMAB A/S	14-Apr-2025	12:21:53 PM	11	1276.00	XCSE
GENMAB A/S	14-Apr-2025	12:25:09 PM	84	1275.00	XCSE
GENMAB A/S	14-Apr-2025	12:27:45 PM	30	1278.00	XCSE
GENMAB A/S	14-Apr-2025	12:27:45 PM	10	1278.00	XCSE
GENMAB A/S	14-Apr-2025	12:27:45 PM	35	1278.00	XCSE
GENMAB A/S	14-Apr-2025	12:27:45 PM	37	1278.00	XCSE
GENMAB A/S	14-Apr-2025	12:27:46 PM	24	1278.00	XCSE
GENMAB A/S	14-Apr-2025	12:27:46 PM	10	1278.00	XCSE
GENMAB A/S	14-Apr-2025	12:27:46 PM	11	1278.00	XCSE
GENMAB A/S	14-Apr-2025	12:27:46 PM	30	1278.00	XCSE
GENMAB A/S	14-Apr-2025	12:27:46 PM	11	1278.00	XCSE
GENMAB A/S	14-Apr-2025	12:27:46 PM	26	1278.00	XCSE
GENMAB A/S	14-Apr-2025	12:27:56 PM	27	1277.50	XCSE
GENMAB A/S	14-Apr-2025	12:28:47 PM	47	1277.50	XCSE
GENMAB A/S	14-Apr-2025	12:29:03 PM	83	1277.00	XCSE
GENMAB A/S	14-Apr-2025	12:29:03 PM	38	1277.00	XCSE
GENMAB A/S	14-Apr-2025	12:29:03 PM	84	1277.00	CEUX
GENMAB A/S	14-Apr-2025	12:29:03 PM	10	1277.00	CEUX
GENMAB A/S	14-Apr-2025	12:30:13 PM	84	1276.00	CEUX
GENMAB A/S	14-Apr-2025	12:32:39 PM	66	1276.00	XCSE
GENMAB A/S	14-Apr-2025	12:34:13 PM	23	1276.00	XCSE
GENMAB A/S	14-Apr-2025	12:34:13 PM	10	1276.00	XCSE
GENMAB A/S	14-Apr-2025	12:34:13 PM	53	1276.00	TQEX

Exhibit 99.1(a)

APPENDIX Share buy-back programme - Specification for April 14 – April 18, 2025

GENMAB A/S	14-Apr-2025	12:34:13 PM	39	1276.00	AQEU
GENMAB A/S	14-Apr-2025	12:34:49 PM	84	1275.00	XCSE
GENMAB A/S	14-Apr-2025	12:34:49 PM	27	1275.50	XCSE
GENMAB A/S	14-Apr-2025	12:34:49 PM	11	1275.50	XCSE
GENMAB A/S	14-Apr-2025	12:34:49 PM	43	1275.50	XCSE
GENMAB A/S	14-Apr-2025	12:34:49 PM	31	1275.00	TQEX
GENMAB A/S	14-Apr-2025	12:34:49 PM	28	1275.00	AQEU
GENMAB A/S	14-Apr-2025	12:34:49 PM	36	1275.50	CEUX
GENMAB A/S	14-Apr-2025	12:34:49 PM	2	1275.50	CEUX
GENMAB A/S	14-Apr-2025	12:34:49 PM	47	1275.50	CEUX
GENMAB A/S	14-Apr-2025	12:34:49 PM	86	1275.00	CEUX
GENMAB A/S	14-Apr-2025	12:35:50 PM	51	1275.00	XCSE
GENMAB A/S	14-Apr-2025	12:35:50 PM	35	1275.00	XCSE
GENMAB A/S	14-Apr-2025	12:40:28 PM	31	1275.00	XCSE
GENMAB A/S	14-Apr-2025	12:40:28 PM	54	1275.00	XCSE
GENMAB A/S	14-Apr-2025	12:40:41 PM	11	1275.00	XCSE
GENMAB A/S	14-Apr-2025	12:40:41 PM	11	1275.00	XCSE
GENMAB A/S	14-Apr-2025	12:40:41 PM	1	1275.00	XCSE
GENMAB A/S	14-Apr-2025	12:40:41 PM	5	1275.00	CEUX
GENMAB A/S	14-Apr-2025	12:40:41 PM	5	1275.00	CEUX
GENMAB A/S	14-Apr-2025	12:40:41 PM	6	1275.00	CEUX
GENMAB A/S	14-Apr-2025	12:41:45 PM	35	1275.00	XCSE
GENMAB A/S	14-Apr-2025	12:41:45 PM	43	1275.00	XCSE
GENMAB A/S	14-Apr-2025	12:41:45 PM	34	1275.00	XCSE
GENMAB A/S	14-Apr-2025	12:41:45 PM	13	1275.00	XCSE
GENMAB A/S	14-Apr-2025	12:41:45 PM	43	1275.00	XCSE
GENMAB A/S	14-Apr-2025	12:41:45 PM	13	1275.00	XCSE
GENMAB A/S	14-Apr-2025	12:41:45 PM	13	1275.00	XCSE
GENMAB A/S	14-Apr-2025	12:41:45 PM	30	1275.00	XCSE
GENMAB A/S	14-Apr-2025	12:41:45 PM	36	1275.00	CEUX
GENMAB A/S	14-Apr-2025	12:41:45 PM	5	1275.00	CEUX
GENMAB A/S	14-Apr-2025	12:41:45 PM	1	1275.00	CEUX
GENMAB A/S	14-Apr-2025	12:41:45 PM	48	1275.00	CEUX
GENMAB A/S	14-Apr-2025	12:41:45 PM	6	1274.50	CEUX
GENMAB A/S	14-Apr-2025	12:42:09 PM	64	1273.50	XCSE
GENMAB A/S	14-Apr-2025	12:42:09 PM	1	1274.50	CEUX
GENMAB A/S	14-Apr-2025	12:42:09 PM	16	1274.50	CEUX
GENMAB A/S	14-Apr-2025	12:42:09 PM	13	1274.50	CEUX
GENMAB A/S	14-Apr-2025	12:42:09 PM	11	1274.50	CEUX
GENMAB A/S	14-Apr-2025	12:42:09 PM	22	1274.50	CEUX
GENMAB A/S	14-Apr-2025	12:42:10 PM	1	1274.50	CEUX
GENMAB A/S	14-Apr-2025	12:42:11 PM	2	1274.50	CEUX
GENMAB A/S	14-Apr-2025	12:42:23 PM	36	1274.50	CEUX

Exhibit 99.1(a)

APPENDIX Share buy-back programme - Specification for April 14 – April 18, 2025

GENMAB A/S	14-Apr-2025	12:42:23 PM	6	1274.50	CEUX
GENMAB A/S	14-Apr-2025	12:42:23 PM	5	1274.50	CEUX
GENMAB A/S	14-Apr-2025	12:42:23 PM	6	1274.50	CEUX
GENMAB A/S	14-Apr-2025	12:42:23 PM	5	1274.50	CEUX
GENMAB A/S	14-Apr-2025	12:42:23 PM	32	1274.50	CEUX
GENMAB A/S	14-Apr-2025	12:42:23 PM	6	1274.50	CEUX
GENMAB A/S	14-Apr-2025	12:42:23 PM	6	1274.50	CEUX
GENMAB A/S	14-Apr-2025	12:42:24 PM	5	1274.50	CEUX
GENMAB A/S	14-Apr-2025	12:42:24 PM	6	1274.50	CEUX
GENMAB A/S	14-Apr-2025	12:42:24 PM	5	1274.50	CEUX
GENMAB A/S	14-Apr-2025	12:42:24 PM	6	1274.50	CEUX
GENMAB A/S	14-Apr-2025	12:42:24 PM	6	1274.50	CEUX
GENMAB A/S	14-Apr-2025	12:42:24 PM	6	1274.50	CEUX
GENMAB A/S	14-Apr-2025	12:42:25 PM	6	1274.50	CEUX
GENMAB A/S	14-Apr-2025	12:42:25 PM	6	1274.50	CEUX
GENMAB A/S	14-Apr-2025	12:42:25 PM	6	1274.50	CEUX
GENMAB A/S	14-Apr-2025	12:42:25 PM	5	1274.50	CEUX
GENMAB A/S	14-Apr-2025	12:42:25 PM	5	1274.50	CEUX
GENMAB A/S	14-Apr-2025	12:42:25 PM	5	1274.50	CEUX
GENMAB A/S	14-Apr-2025	12:42:25 PM	5	1274.50	CEUX
GENMAB A/S	14-Apr-2025	12:42:25 PM	5	1274.50	CEUX
GENMAB A/S	14-Apr-2025	12:42:25 PM	5	1274.50	CEUX
GENMAB A/S	14-Apr-2025	12:42:26 PM	5	1274.50	CEUX
GENMAB A/S	14-Apr-2025	12:42:26 PM	6	1274.50	CEUX
GENMAB A/S	14-Apr-2025	12:42:26 PM	6	1274.50	CEUX
GENMAB A/S	14-Apr-2025	12:42:26 PM	6	1274.50	CEUX
GENMAB A/S	14-Apr-2025	12:42:26 PM	6	1274.50	CEUX
GENMAB A/S	14-Apr-2025	12:42:26 PM	6	1274.50	CEUX
GENMAB A/S	14-Apr-2025	12:42:27 PM	5	1274.50	CEUX
GENMAB A/S	14-Apr-2025	12:42:27 PM	6	1274.50	CEUX
GENMAB A/S	14-Apr-2025	12:42:27 PM	5	1274.50	CEUX
GENMAB A/S	14-Apr-2025	12:42:27 PM	6	1274.50	CEUX
GENMAB A/S	14-Apr-2025	12:42:27 PM	5	1274.50	CEUX
GENMAB A/S	14-Apr-2025	12:42:27 PM	5	1274.50	CEUX
GENMAB A/S	14-Apr-2025	12:42:27 PM	5	1274.50	CEUX
GENMAB A/S	14-Apr-2025	12:42:27 PM	6	1274.50	CEUX
GENMAB A/S	14-Apr-2025	12:42:27 PM	5	1274.50	CEUX
GENMAB A/S	14-Apr-2025	12:42:57 PM	15	1274.50	CEUX
GENMAB A/S	14-Apr-2025	12:42:57 PM	6	1274.50	CEUX
GENMAB A/S	14-Apr-2025	12:42:57 PM	6	1274.50	CEUX
GENMAB A/S	14-Apr-2025	12:42:57 PM	6	1274.50	CEUX
GENMAB A/S	14-Apr-2025	12:42:57 PM	11	1274.50	CEUX
GENMAB A/S	14-Apr-2025	12:42:57 PM	7	1274.50	CEUX

Exhibit 99.1(a)

APPENDIX Share buy-back programme - Specification for April 14 – April 18, 2025

GENMAB A/S	14-Apr-2025	12:43:14 PM	24	1274.00	TQEX
GENMAB A/S	14-Apr-2025	12:43:14 PM	7	1274.00	TQEX
GENMAB A/S	14-Apr-2025	12:43:14 PM	25	1274.00	AQEU
GENMAB A/S	14-Apr-2025	12:43:14 PM	84	1274.00	CEUX
GENMAB A/S	14-Apr-2025	12:43:40 PM	47	1274.00	XCSE
GENMAB A/S	14-Apr-2025	12:43:40 PM	6	1274.00	XCSE
GENMAB A/S	14-Apr-2025	12:47:09 PM	23	1273.50	XCSE
GENMAB A/S	14-Apr-2025	12:47:15 PM	63	1274.00	TQEX
GENMAB A/S	14-Apr-2025	12:47:15 PM	67	1274.00	CEUX
GENMAB A/S	14-Apr-2025	12:47:47 PM	22	1274.00	CEUX
GENMAB A/S	14-Apr-2025	12:49:39 PM	35	1275.00	TQEX
GENMAB A/S	14-Apr-2025	12:49:53 PM	11	1275.00	TQEX
GENMAB A/S	14-Apr-2025	12:51:13 PM	12	1275.00	XCSE
GENMAB A/S	14-Apr-2025	12:51:13 PM	1	1275.00	XCSE
GENMAB A/S	14-Apr-2025	12:51:13 PM	11	1275.00	XCSE
GENMAB A/S	14-Apr-2025	12:51:13 PM	34	1275.00	XCSE
GENMAB A/S	14-Apr-2025	12:51:13 PM	85	1274.50	CEUX
GENMAB A/S	14-Apr-2025	12:53:26 PM	49	1275.00	XCSE
GENMAB A/S	14-Apr-2025	12:53:26 PM	13	1275.00	XCSE
GENMAB A/S	14-Apr-2025	12:53:26 PM	43	1275.00	XCSE
GENMAB A/S	14-Apr-2025	12:53:26 PM	7	1275.00	XCSE
GENMAB A/S	14-Apr-2025	12:53:27 PM	14	1274.50	AQEU
GENMAB A/S	14-Apr-2025	12:53:29 PM	40	1274.50	AQEU
GENMAB A/S	14-Apr-2025	12:53:38 PM	83	1274.50	CEUX
GENMAB A/S	14-Apr-2025	12:53:39 PM	46	1275.00	XCSE
GENMAB A/S	14-Apr-2025	12:53:39 PM	12	1275.00	XCSE
GENMAB A/S	14-Apr-2025	12:53:39 PM	43	1275.00	XCSE
GENMAB A/S	14-Apr-2025	12:53:39 PM	11	1275.00	XCSE
GENMAB A/S	14-Apr-2025	12:53:40 PM	10	1275.00	XCSE
GENMAB A/S	14-Apr-2025	12:53:40 PM	11	1275.00	XCSE
GENMAB A/S	14-Apr-2025	12:53:40 PM	43	1275.00	XCSE
GENMAB A/S	14-Apr-2025	12:53:40 PM	48	1275.00	XCSE
GENMAB A/S	14-Apr-2025	12:54:54 PM	28	1275.50	XCSE
GENMAB A/S	14-Apr-2025	12:54:54 PM	12	1275.50	XCSE
GENMAB A/S	14-Apr-2025	12:54:54 PM	12	1275.50	XCSE
GENMAB A/S	14-Apr-2025	12:54:54 PM	13	1275.50	XCSE
GENMAB A/S	14-Apr-2025	12:54:54 PM	43	1275.50	XCSE
GENMAB A/S	14-Apr-2025	12:54:54 PM	10	1275.50	XCSE
GENMAB A/S	14-Apr-2025	12:54:54 PM	43	1275.50	XCSE
GENMAB A/S	14-Apr-2025	12:54:54 PM	12	1275.50	XCSE
GENMAB A/S	14-Apr-2025	12:54:54 PM	13	1275.50	XCSE
GENMAB A/S	14-Apr-2025	12:55:48 PM	45	1275.00	XCSE
GENMAB A/S	14-Apr-2025	12:56:09 PM	9	1274.00	TQEX

Exhibit 99.1(a)

APPENDIX Share buy-back programme - Specification for April 14 – April 18, 2025

GENMAB A/S	14-Apr-2025	12:56:09 PM	9	1274.00	TQEX
GENMAB A/S	14-Apr-2025	12:56:09 PM	13	1275.00	CEUX
GENMAB A/S	14-Apr-2025	12:56:15 PM	11	1274.50	XCSE
GENMAB A/S	14-Apr-2025	12:56:16 PM	1	1274.50	XCSE
GENMAB A/S	14-Apr-2025	12:56:20 PM	57	1274.50	CEUX
GENMAB A/S	14-Apr-2025	12:57:25 PM	86	1275.00	XCSE
GENMAB A/S	14-Apr-2025	12:57:25 PM	25	1275.00	TQEX
GENMAB A/S	14-Apr-2025	12:57:29 PM	27	1274.50	CEUX
GENMAB A/S	14-Apr-2025	12:57:30 PM	10	1275.00	XCSE
GENMAB A/S	14-Apr-2025	12:57:30 PM	32	1275.00	XCSE
GENMAB A/S	14-Apr-2025	12:58:08 PM	59	1274.00	XCSE
GENMAB A/S	14-Apr-2025	12:58:09 PM	28	1274.50	AQEU
GENMAB A/S	14-Apr-2025	12:58:11 PM	27	1274.00	XCSE
GENMAB A/S	14-Apr-2025	12:58:11 PM	26	1274.00	TQEX
GENMAB A/S	14-Apr-2025	1:00:08 PM	68	1274.00	XCSE
GENMAB A/S	14-Apr-2025	1:00:08 PM	36	1274.00	CEUX
GENMAB A/S	14-Apr-2025	1:00:23 PM	11	1274.00	CEUX
GENMAB A/S	14-Apr-2025	1:00:30 PM	26	1274.00	XCSE
GENMAB A/S	14-Apr-2025	1:01:16 PM	7	1274.00	XCSE
GENMAB A/S	14-Apr-2025	1:01:16 PM	47	1274.00	XCSE
GENMAB A/S	14-Apr-2025	1:01:16 PM	43	1274.00	XCSE
GENMAB A/S	14-Apr-2025	1:01:16 PM	5	1274.00	XCSE
GENMAB A/S	14-Apr-2025	1:02:50 PM	39	1275.00	XCSE
GENMAB A/S	14-Apr-2025	1:02:50 PM	43	1275.00	XCSE
GENMAB A/S	14-Apr-2025	1:02:50 PM	11	1275.00	XCSE
GENMAB A/S	14-Apr-2025	1:02:50 PM	10	1275.00	XCSE
GENMAB A/S	14-Apr-2025	1:02:50 PM	9	1275.00	XCSE
GENMAB A/S	14-Apr-2025	1:04:40 PM	1	1275.00	XCSE
GENMAB A/S	14-Apr-2025	1:04:40 PM	43	1275.00	XCSE
GENMAB A/S	14-Apr-2025	1:04:40 PM	11	1275.00	XCSE
GENMAB A/S	14-Apr-2025	1:04:40 PM	12	1275.00	XCSE
GENMAB A/S	14-Apr-2025	1:04:40 PM	21	1275.00	XCSE
GENMAB A/S	14-Apr-2025	1:04:41 PM	36	1274.50	CEUX
GENMAB A/S	14-Apr-2025	1:06:23 PM	85	1274.00	CEUX
GENMAB A/S	14-Apr-2025	1:06:40 PM	88	1274.00	XCSE
GENMAB A/S	14-Apr-2025	1:06:40 PM	43	1274.50	XCSE
GENMAB A/S	14-Apr-2025	1:06:40 PM	12	1274.50	XCSE
GENMAB A/S	14-Apr-2025	1:06:40 PM	13	1274.50	XCSE
GENMAB A/S	14-Apr-2025	1:06:40 PM	4	1274.50	XCSE
GENMAB A/S	14-Apr-2025	1:06:40 PM	13	1274.50	XCSE
GENMAB A/S	14-Apr-2025	1:06:40 PM	27	1274.50	XCSE
GENMAB A/S	14-Apr-2025	1:06:40 PM	26	1274.00	TQEX
GENMAB A/S	14-Apr-2025	1:06:40 PM	30	1274.00	CEUX

Exhibit 99.1(a)

APPENDIX Share buy-back programme - Specification for April 14 – April 18, 2025

GENMAB A/S	14-Apr-2025	1:06:49 PM	10	1273.00	XCSE
GENMAB A/S	14-Apr-2025	1:06:49 PM	41	1273.50	AQEU
GENMAB A/S	14-Apr-2025	1:06:49 PM	2	1273.50	AQEU
GENMAB A/S	14-Apr-2025	1:06:49 PM	11	1273.50	AQEU
GENMAB A/S	14-Apr-2025	1:07:27 PM	77	1273.00	XCSE
GENMAB A/S	14-Apr-2025	1:07:27 PM	3	1273.50	CEUX
GENMAB A/S	14-Apr-2025	1:07:27 PM	9	1273.50	CEUX
GENMAB A/S	14-Apr-2025	1:07:27 PM	36	1273.50	CEUX
GENMAB A/S	14-Apr-2025	1:07:27 PM	1	1273.50	CEUX
GENMAB A/S	14-Apr-2025	1:07:27 PM	47	1273.50	CEUX
GENMAB A/S	14-Apr-2025	1:07:27 PM	4	1273.00	CEUX
GENMAB A/S	14-Apr-2025	1:07:27 PM	20	1273.00	CEUX
GENMAB A/S	14-Apr-2025	1:07:27 PM	64	1273.00	CEUX
GENMAB A/S	14-Apr-2025	1:07:48 PM	15	1272.50	TQEX
GENMAB A/S	14-Apr-2025	1:08:04 PM	33	1272.50	TQEX
GENMAB A/S	14-Apr-2025	1:08:04 PM	42	1272.50	AQEU
GENMAB A/S	14-Apr-2025	1:08:04 PM	12	1272.00	CEUX
GENMAB A/S	14-Apr-2025	1:08:04 PM	73	1272.00	CEUX
GENMAB A/S	14-Apr-2025	1:08:06 PM	12	1271.50	XCSE
GENMAB A/S	14-Apr-2025	1:08:06 PM	74	1271.50	XCSE
GENMAB A/S	14-Apr-2025	1:12:33 PM	8	1271.00	CEUX
GENMAB A/S	14-Apr-2025	1:12:51 PM	74	1271.00	CEUX
GENMAB A/S	14-Apr-2025	1:13:00 PM	27	1271.00	TQEX
GENMAB A/S	14-Apr-2025	1:13:00 PM	27	1271.00	AQEU
GENMAB A/S	14-Apr-2025	1:13:00 PM	3	1271.00	CEUX
GENMAB A/S	14-Apr-2025	1:13:46 PM	11	1271.50	XCSE
GENMAB A/S	14-Apr-2025	1:13:46 PM	11	1271.50	XCSE
GENMAB A/S	14-Apr-2025	1:13:46 PM	43	1271.50	XCSE
GENMAB A/S	14-Apr-2025	1:13:47 PM	10	1271.50	XCSE
GENMAB A/S	14-Apr-2025	1:13:47 PM	43	1271.50	XCSE
GENMAB A/S	14-Apr-2025	1:13:47 PM	30	1271.50	XCSE
GENMAB A/S	14-Apr-2025	1:13:47 PM	12	1271.50	XCSE
GENMAB A/S	14-Apr-2025	1:13:47 PM	11	1271.50	XCSE
GENMAB A/S	14-Apr-2025	1:14:13 PM	36	1270.50	XCSE
GENMAB A/S	14-Apr-2025	1:14:13 PM	49	1270.50	XCSE
GENMAB A/S	14-Apr-2025	1:14:13 PM	25	1271.00	TQEX
GENMAB A/S	14-Apr-2025	1:14:13 PM	25	1271.00	AQEU
GENMAB A/S	14-Apr-2025	1:14:58 PM	16	1270.00	AQEU
GENMAB A/S	14-Apr-2025	1:15:30 PM	89	1269.50	XCSE
GENMAB A/S	14-Apr-2025	1:16:27 PM	4	1270.00	CEUX
GENMAB A/S	14-Apr-2025	1:16:27 PM	26	1270.00	CEUX
GENMAB A/S	14-Apr-2025	1:16:28 PM	26	1270.00	TQEX
GENMAB A/S	14-Apr-2025	1:16:53 PM	86	1269.00	XCSE

Exhibit 99.1(a)

APPENDIX Share buy-back programme - Specification for April 14 – April 18, 2025

GENMAB A/S	14-Apr-2025	1:16:53 PM	86	1269.50	CEUX
GENMAB A/S	14-Apr-2025	1:18:29 PM	7	1268.50	XCSE
GENMAB A/S	14-Apr-2025	1:18:29 PM	25	1268.50	AQEU
GENMAB A/S	14-Apr-2025	1:18:29 PM	82	1268.50	CEUX
GENMAB A/S	14-Apr-2025	1:18:30 PM	85	1268.00	XCSE
GENMAB A/S	14-Apr-2025	1:18:53 PM	86	1269.00	XCSE
GENMAB A/S	14-Apr-2025	1:21:41 PM	89	1269.50	XCSE
GENMAB A/S	14-Apr-2025	1:21:41 PM	33	1269.50	CEUX
GENMAB A/S	14-Apr-2025	1:21:42 PM	27	1269.50	AQEU
GENMAB A/S	14-Apr-2025	1:21:42 PM	53	1269.50	CEUX
GENMAB A/S	14-Apr-2025	1:24:11 PM	13	1270.00	XCSE
GENMAB A/S	14-Apr-2025	1:24:11 PM	43	1270.00	XCSE
GENMAB A/S	14-Apr-2025	1:24:11 PM	31	1270.00	XCSE
GENMAB A/S	14-Apr-2025	1:24:11 PM	25	1270.00	XCSE
GENMAB A/S	14-Apr-2025	1:24:12 PM	13	1269.50	CEUX
GENMAB A/S	14-Apr-2025	1:24:53 PM	72	1269.50	CEUX
GENMAB A/S	14-Apr-2025	1:25:02 PM	12	1270.00	XCSE
GENMAB A/S	14-Apr-2025	1:25:02 PM	11	1270.00	XCSE
GENMAB A/S	14-Apr-2025	1:25:02 PM	25	1270.00	XCSE
GENMAB A/S	14-Apr-2025	1:25:02 PM	31	1270.00	XCSE
GENMAB A/S	14-Apr-2025	1:25:02 PM	33	1270.00	XCSE
GENMAB A/S	14-Apr-2025	1:25:02 PM	25	1269.50	TQEX
GENMAB A/S	14-Apr-2025	1:25:04 PM	84	1269.00	XCSE
GENMAB A/S	14-Apr-2025	1:25:04 PM	15	1269.50	AQEU
GENMAB A/S	14-Apr-2025	1:25:50 PM	82	1270.50	XCSE
GENMAB A/S	14-Apr-2025	1:25:50 PM	86	1270.50	CEUX
GENMAB A/S	14-Apr-2025	1:27:53 PM	11	1272.00	TQEX
GENMAB A/S	14-Apr-2025	1:27:58 PM	14	1272.00	TQEX
GENMAB A/S	14-Apr-2025	1:29:16 PM	87	1271.50	XCSE
GENMAB A/S	14-Apr-2025	1:29:16 PM	25	1272.00	XCSE
GENMAB A/S	14-Apr-2025	1:29:16 PM	41	1271.50	CEUX
GENMAB A/S	14-Apr-2025	1:29:16 PM	47	1271.50	CEUX
GENMAB A/S	14-Apr-2025	1:31:00 PM	49	1272.00	XCSE
GENMAB A/S	14-Apr-2025	1:31:20 PM	12	1272.00	XCSE
GENMAB A/S	14-Apr-2025	1:31:20 PM	21	1272.00	XCSE
GENMAB A/S	14-Apr-2025	1:31:45 PM	14	1271.50	CEUX
GENMAB A/S	14-Apr-2025	1:31:50 PM	13	1272.00	XCSE
GENMAB A/S	14-Apr-2025	1:31:50 PM	28	1272.00	XCSE
GENMAB A/S	14-Apr-2025	1:31:51 PM	17	1271.50	AQEU
GENMAB A/S	14-Apr-2025	1:32:02 PM	55	1271.50	CEUX
GENMAB A/S	14-Apr-2025	1:32:13 PM	84	1271.50	XCSE
GENMAB A/S	14-Apr-2025	1:32:13 PM	16	1271.50	CEUX
GENMAB A/S	14-Apr-2025	1:32:14 PM	9	1271.50	AQEU

Exhibit 99.1(a)

APPENDIX Share buy-back programme - Specification for April 14 – April 18, 2025

GENMAB A/S	14-Apr-2025	1:34:27 PM	41	1271.50	XCSE
GENMAB A/S	14-Apr-2025	1:34:27 PM	71	1271.50	XCSE
GENMAB A/S	14-Apr-2025	1:34:29 PM	25	1271.00	TQEX
GENMAB A/S	14-Apr-2025	1:34:29 PM	21	1270.50	CEUX
GENMAB A/S	14-Apr-2025	1:34:39 PM	83	1270.50	XCSE
GENMAB A/S	14-Apr-2025	1:34:39 PM	68	1270.50	CEUX
GENMAB A/S	14-Apr-2025	1:34:40 PM	13	1270.00	TQEX
GENMAB A/S	14-Apr-2025	1:34:40 PM	12	1270.00	AQEU
GENMAB A/S	14-Apr-2025	1:37:14 PM	11	1271.00	XCSE
GENMAB A/S	14-Apr-2025	1:37:14 PM	22	1271.00	XCSE
GENMAB A/S	14-Apr-2025	1:37:14 PM	29	1271.00	XCSE
GENMAB A/S	14-Apr-2025	1:37:14 PM	31	1270.50	TQEX
GENMAB A/S	14-Apr-2025	1:38:10 PM	47	1271.00	XCSE
GENMAB A/S	14-Apr-2025	1:38:10 PM	12	1271.00	XCSE
GENMAB A/S	14-Apr-2025	1:38:10 PM	10	1271.00	XCSE
GENMAB A/S	14-Apr-2025	1:38:10 PM	41	1271.00	XCSE
GENMAB A/S	14-Apr-2025	1:38:10 PM	2	1271.00	XCSE
GENMAB A/S	14-Apr-2025	1:38:20 PM	85	1270.50	XCSE
GENMAB A/S	14-Apr-2025	1:40:59 PM	36	1270.50	CEUX
GENMAB A/S	14-Apr-2025	1:44:09 PM	20	1270.50	CEUX
GENMAB A/S	14-Apr-2025	1:44:10 PM	12	1270.50	XCSE
GENMAB A/S	14-Apr-2025	1:44:10 PM	15	1270.50	CEUX
GENMAB A/S	14-Apr-2025	1:45:11 PM	31	1270.50	XCSE
GENMAB A/S	14-Apr-2025	1:45:11 PM	52	1270.50	XCSE
GENMAB A/S	14-Apr-2025	1:46:09 PM	41	1270.50	XCSE
GENMAB A/S	14-Apr-2025	1:46:09 PM	12	1270.50	XCSE
GENMAB A/S	14-Apr-2025	1:46:09 PM	22	1270.50	XCSE
GENMAB A/S	14-Apr-2025	1:46:09 PM	36	1270.50	CEUX
GENMAB A/S	14-Apr-2025	1:46:09 PM	14	1270.50	CEUX
GENMAB A/S	14-Apr-2025	1:46:35 PM	26	1270.50	TQEX
GENMAB A/S	14-Apr-2025	1:47:39 PM	54	1269.50	XCSE
GENMAB A/S	14-Apr-2025	1:47:39 PM	14	1270.50	CEUX
GENMAB A/S	14-Apr-2025	1:48:58 PM	19	1270.00	AQEU
GENMAB A/S	14-Apr-2025	1:48:58 PM	36	1270.00	CEUX
GENMAB A/S	14-Apr-2025	1:48:58 PM	3	1270.00	CEUX
GENMAB A/S	14-Apr-2025	1:48:59 PM	50	1270.00	CEUX
GENMAB A/S	14-Apr-2025	1:48:59 PM	11	1270.00	CEUX
GENMAB A/S	14-Apr-2025	1:50:29 PM	35	1269.50	XCSE
GENMAB A/S	14-Apr-2025	1:50:29 PM	28	1269.50	TQEX
GENMAB A/S	14-Apr-2025	1:50:29 PM	2	1269.50	CEUX
GENMAB A/S	14-Apr-2025	1:50:29 PM	20	1269.50	CEUX
GENMAB A/S	14-Apr-2025	1:50:53 PM	63	1269.50	CEUX
GENMAB A/S	14-Apr-2025	1:51:10 PM	45	1270.00	CEUX

Exhibit 99.1(a)

APPENDIX Share buy-back programme - Specification for April 14 – April 18, 2025

GENMAB A/S	14-Apr-2025	1:51:42 PM	37	1270.00	CEUX
GENMAB A/S	14-Apr-2025	1:53:23 PM	6	1271.00	XCSE
GENMAB A/S	14-Apr-2025	1:53:23 PM	43	1271.00	XCSE
GENMAB A/S	14-Apr-2025	1:53:23 PM	12	1271.00	XCSE
GENMAB A/S	14-Apr-2025	1:53:23 PM	10	1271.00	XCSE
GENMAB A/S	14-Apr-2025	1:53:23 PM	35	1271.00	XCSE
GENMAB A/S	14-Apr-2025	1:53:23 PM	43	1271.00	XCSE
GENMAB A/S	14-Apr-2025	1:53:23 PM	10	1271.00	XCSE
GENMAB A/S	14-Apr-2025	1:53:23 PM	11	1271.00	XCSE
GENMAB A/S	14-Apr-2025	1:53:23 PM	32	1271.00	CEUX
GENMAB A/S	14-Apr-2025	1:53:23 PM	11	1271.00	CEUX
GENMAB A/S	14-Apr-2025	1:53:23 PM	14	1271.00	CEUX
GENMAB A/S	14-Apr-2025	1:53:23 PM	30	1271.00	CEUX
GENMAB A/S	14-Apr-2025	1:53:23 PM	5	1271.00	CEUX
GENMAB A/S	14-Apr-2025	1:53:23 PM	6	1271.00	CEUX
GENMAB A/S	14-Apr-2025	1:53:37 PM	28	1271.00	XCSE
GENMAB A/S	14-Apr-2025	1:53:50 PM	24	1271.00	XCSE
GENMAB A/S	14-Apr-2025	1:53:50 PM	14	1271.00	XCSE
GENMAB A/S	14-Apr-2025	1:53:50 PM	19	1271.00	XCSE
GENMAB A/S	14-Apr-2025	1:54:49 PM	26	1271.50	XCSE
GENMAB A/S	14-Apr-2025	1:54:49 PM	13	1271.50	XCSE
GENMAB A/S	14-Apr-2025	1:54:49 PM	13	1271.50	XCSE
GENMAB A/S	14-Apr-2025	1:55:16 PM	42	1271.50	XCSE
GENMAB A/S	14-Apr-2025	1:55:16 PM	12	1271.50	XCSE
GENMAB A/S	14-Apr-2025	1:55:16 PM	12	1271.50	XCSE
GENMAB A/S	14-Apr-2025	1:55:16 PM	5	1271.50	CEUX
GENMAB A/S	14-Apr-2025	1:55:16 PM	5	1271.50	CEUX
GENMAB A/S	14-Apr-2025	1:55:17 PM	36	1271.50	CEUX
GENMAB A/S	14-Apr-2025	1:55:17 PM	5	1271.50	CEUX
GENMAB A/S	14-Apr-2025	1:55:17 PM	5	1271.50	CEUX
GENMAB A/S	14-Apr-2025	1:55:18 PM	36	1271.50	CEUX
GENMAB A/S	14-Apr-2025	1:56:02 PM	6	1271.50	CEUX
GENMAB A/S	14-Apr-2025	1:56:29 PM	35	1271.00	XCSE
GENMAB A/S	14-Apr-2025	1:56:29 PM	11	1271.00	XCSE
GENMAB A/S	14-Apr-2025	1:56:29 PM	43	1271.00	XCSE
GENMAB A/S	14-Apr-2025	1:56:29 PM	11	1271.00	XCSE
GENMAB A/S	14-Apr-2025	1:56:29 PM	4	1271.00	XCSE
GENMAB A/S	14-Apr-2025	1:56:29 PM	13	1271.00	XCSE
GENMAB A/S	14-Apr-2025	1:56:29 PM	43	1271.00	XCSE
GENMAB A/S	14-Apr-2025	1:56:29 PM	10	1271.00	XCSE
GENMAB A/S	14-Apr-2025	1:56:29 PM	12	1271.00	XCSE
GENMAB A/S	14-Apr-2025	1:56:29 PM	34	1271.00	XCSE
GENMAB A/S	14-Apr-2025	1:56:29 PM	30	1271.00	XCSE

Exhibit 99.1(a)

APPENDIX Share buy-back programme - Specification for April 14 – April 18, 2025

GENMAB A/S	14-Apr-2025	1:56:29 PM	12	1271.00	XCSE
GENMAB A/S	14-Apr-2025	1:56:29 PM	13	1271.00	XCSE
GENMAB A/S	14-Apr-2025	1:56:29 PM	10	1271.00	XCSE
GENMAB A/S	14-Apr-2025	1:56:29 PM	43	1271.00	XCSE
GENMAB A/S	14-Apr-2025	1:56:29 PM	4	1271.00	XCSE
GENMAB A/S	14-Apr-2025	1:56:29 PM	36	1271.00	CEUX
GENMAB A/S	14-Apr-2025	1:56:29 PM	6	1271.00	CEUX
GENMAB A/S	14-Apr-2025	1:56:29 PM	5	1271.00	CEUX
GENMAB A/S	14-Apr-2025	1:56:29 PM	6	1271.00	CEUX
GENMAB A/S	14-Apr-2025	1:56:29 PM	1	1271.00	CEUX
GENMAB A/S	14-Apr-2025	1:56:29 PM	47	1271.00	CEUX
GENMAB A/S	14-Apr-2025	1:56:29 PM	30	1270.50	CEUX
GENMAB A/S	14-Apr-2025	1:56:30 PM	12	1271.00	XCSE
GENMAB A/S	14-Apr-2025	1:56:30 PM	13	1271.00	XCSE
GENMAB A/S	14-Apr-2025	1:56:30 PM	43	1271.00	XCSE
GENMAB A/S	14-Apr-2025	1:56:30 PM	13	1271.00	XCSE
GENMAB A/S	14-Apr-2025	1:56:30 PM	31	1271.00	XCSE
GENMAB A/S	14-Apr-2025	1:56:30 PM	11	1271.00	XCSE
GENMAB A/S	14-Apr-2025	1:56:30 PM	12	1271.00	XCSE
GENMAB A/S	14-Apr-2025	1:56:30 PM	13	1271.00	XCSE
GENMAB A/S	14-Apr-2025	1:56:30 PM	43	1271.00	XCSE
GENMAB A/S	14-Apr-2025	1:56:30 PM	33	1271.00	XCSE
GENMAB A/S	14-Apr-2025	1:56:30 PM	25	1270.50	TQEX
GENMAB A/S	14-Apr-2025	1:56:30 PM	16	1270.50	CEUX
GENMAB A/S	14-Apr-2025	1:56:30 PM	35	1270.50	CEUX
GENMAB A/S	14-Apr-2025	1:56:30 PM	6	1270.50	CEUX
GENMAB A/S	14-Apr-2025	1:56:40 PM	49	1271.00	XCSE
GENMAB A/S	14-Apr-2025	1:56:40 PM	10	1271.00	XCSE
GENMAB A/S	14-Apr-2025	1:56:40 PM	43	1271.00	XCSE
GENMAB A/S	14-Apr-2025	1:56:40 PM	10	1271.00	XCSE
GENMAB A/S	14-Apr-2025	1:56:40 PM	17	1270.50	AQEU
GENMAB A/S	14-Apr-2025	1:56:44 PM	85	1270.00	XCSE
GENMAB A/S	14-Apr-2025	1:56:44 PM	35	1270.50	AQEU
GENMAB A/S	14-Apr-2025	1:58:10 PM	89	1269.00	XCSE
GENMAB A/S	14-Apr-2025	1:58:10 PM	22	1269.50	TQEX
GENMAB A/S	14-Apr-2025	1:58:10 PM	3	1269.50	TQEX
GENMAB A/S	14-Apr-2025	1:58:10 PM	32	1269.00	AQEU
GENMAB A/S	14-Apr-2025	1:58:10 PM	82	1269.00	CEUX
GENMAB A/S	14-Apr-2025	1:58:29 PM	82	1268.00	XCSE
GENMAB A/S	14-Apr-2025	2:00:13 PM	86	1268.00	CEUX
GENMAB A/S	14-Apr-2025	2:01:57 PM	42	1268.50	XCSE
GENMAB A/S	14-Apr-2025	2:01:57 PM	40	1268.50	XCSE
GENMAB A/S	14-Apr-2025	2:01:57 PM	35	1268.50	XCSE

Exhibit 99.1(a)

APPENDIX Share buy-back programme - Specification for April 14 – April 18, 2025

GENMAB A/S	14-Apr-2025	2:01:57 PM	12	1268.50	XCSE
GENMAB A/S	14-Apr-2025	2:02:01 PM	31	1268.50	XCSE
GENMAB A/S	14-Apr-2025	2:02:01 PM	13	1268.00	TQEX
GENMAB A/S	14-Apr-2025	2:03:04 PM	60	1268.00	XCSE
GENMAB A/S	14-Apr-2025	2:03:04 PM	7	1268.00	XCSE
GENMAB A/S	14-Apr-2025	2:03:04 PM	14	1268.00	TQEX
GENMAB A/S	14-Apr-2025	2:03:04 PM	26	1268.00	AQEU
GENMAB A/S	14-Apr-2025	2:03:04 PM	20	1268.00	CEUX
GENMAB A/S	14-Apr-2025	2:03:04 PM	28	1268.00	CEUX
GENMAB A/S	14-Apr-2025	2:03:04 PM	42	1268.00	CEUX
GENMAB A/S	14-Apr-2025	2:03:09 PM	8	1268.50	XCSE
GENMAB A/S	14-Apr-2025	2:04:19 PM	42	1269.00	XCSE
GENMAB A/S	14-Apr-2025	2:04:19 PM	10	1269.00	XCSE
GENMAB A/S	14-Apr-2025	2:04:19 PM	13	1269.00	XCSE
GENMAB A/S	14-Apr-2025	2:04:22 PM	10	1269.00	XCSE
GENMAB A/S	14-Apr-2025	2:04:22 PM	13	1269.00	XCSE
GENMAB A/S	14-Apr-2025	2:04:47 PM	2	1268.50	XCSE
GENMAB A/S	14-Apr-2025	2:04:52 PM	10	1269.50	XCSE
GENMAB A/S	14-Apr-2025	2:04:52 PM	43	1269.50	XCSE
GENMAB A/S	14-Apr-2025	2:04:52 PM	11	1269.50	XCSE
GENMAB A/S	14-Apr-2025	2:04:52 PM	11	1269.50	XCSE
GENMAB A/S	14-Apr-2025	2:04:52 PM	2	1269.00	TQEX
GENMAB A/S	14-Apr-2025	2:04:52 PM	2	1269.00	TQEX
GENMAB A/S	14-Apr-2025	2:05:11 PM	32	1269.00	TQEX
GENMAB A/S	14-Apr-2025	2:05:20 PM	11	1269.50	XCSE
GENMAB A/S	14-Apr-2025	2:05:20 PM	12	1269.50	XCSE
GENMAB A/S	14-Apr-2025	2:05:20 PM	43	1269.50	XCSE
GENMAB A/S	14-Apr-2025	2:05:20 PM	35	1269.50	XCSE
GENMAB A/S	14-Apr-2025	2:05:20 PM	11	1269.50	XCSE
GENMAB A/S	14-Apr-2025	2:05:34 PM	77	1268.50	XCSE
GENMAB A/S	14-Apr-2025	2:05:34 PM	6	1268.50	XCSE
GENMAB A/S	14-Apr-2025	2:05:34 PM	36	1268.50	CEUX
GENMAB A/S	14-Apr-2025	2:05:35 PM	32	1268.50	CEUX
GENMAB A/S	14-Apr-2025	2:05:35 PM	65	1268.00	CEUX
GENMAB A/S	14-Apr-2025	2:07:05 PM	24	1268.00	CEUX
GENMAB A/S	14-Apr-2025	2:08:49 PM	7	1268.00	XCSE
GENMAB A/S	14-Apr-2025	2:08:49 PM	43	1268.00	XCSE
GENMAB A/S	14-Apr-2025	2:08:49 PM	37	1268.00	XCSE
GENMAB A/S	14-Apr-2025	2:08:49 PM	4	1267.50	XCSE
GENMAB A/S	14-Apr-2025	2:08:49 PM	3	1267.50	XCSE
GENMAB A/S	14-Apr-2025	2:08:49 PM	6	1267.50	XCSE
GENMAB A/S	14-Apr-2025	2:08:49 PM	5	1267.50	XCSE
GENMAB A/S	14-Apr-2025	2:08:49 PM	1	1268.00	TQEX

Exhibit 99.1(a)

APPENDIX Share buy-back programme - Specification for April 14 – April 18, 2025

GENMAB A/S	14-Apr-2025	2:08:49 PM	24	1268.00	TQEX
GENMAB A/S	14-Apr-2025	2:08:49 PM	8	1268.00	AQEU
GENMAB A/S	14-Apr-2025	2:08:49 PM	37	1268.00	AQEU
GENMAB A/S	14-Apr-2025	2:08:49 PM	2	1268.00	CEUX
GENMAB A/S	14-Apr-2025	2:09:09 PM	3	1267.50	XCSE
GENMAB A/S	14-Apr-2025	2:09:29 PM	64	1267.50	XCSE
GENMAB A/S	14-Apr-2025	2:09:30 PM	5	1268.00	XCSE
GENMAB A/S	14-Apr-2025	2:09:30 PM	10	1268.00	XCSE
GENMAB A/S	14-Apr-2025	2:09:30 PM	13	1268.00	XCSE
GENMAB A/S	14-Apr-2025	2:09:30 PM	10	1268.00	XCSE
GENMAB A/S	14-Apr-2025	2:09:30 PM	10	1268.00	XCSE
GENMAB A/S	14-Apr-2025	2:09:30 PM	7	1268.00	XCSE
GENMAB A/S	14-Apr-2025	2:09:48 PM	17	1268.50	XCSE
GENMAB A/S	14-Apr-2025	2:09:54 PM	31	1268.50	XCSE
GENMAB A/S	14-Apr-2025	2:09:54 PM	36	1268.50	CEUX
GENMAB A/S	14-Apr-2025	2:09:54 PM	11	1268.50	CEUX
GENMAB A/S	14-Apr-2025	2:09:54 PM	5	1268.50	CEUX
GENMAB A/S	14-Apr-2025	2:09:54 PM	6	1268.50	CEUX
GENMAB A/S	14-Apr-2025	2:09:54 PM	5	1268.50	CEUX
GENMAB A/S	14-Apr-2025	2:10:08 PM	6	1268.50	CEUX
GENMAB A/S	14-Apr-2025	2:10:09 PM	11	1268.50	CEUX
GENMAB A/S	14-Apr-2025	2:10:09 PM	6	1268.50	CEUX
GENMAB A/S	14-Apr-2025	2:10:09 PM	5	1268.50	CEUX
GENMAB A/S	14-Apr-2025	2:10:09 PM	3	1268.50	CEUX
GENMAB A/S	14-Apr-2025	2:10:09 PM	2	1268.50	CEUX
GENMAB A/S	14-Apr-2025	2:10:09 PM	5	1268.50	CEUX
GENMAB A/S	14-Apr-2025	2:10:09 PM	6	1268.50	CEUX
GENMAB A/S	14-Apr-2025	2:10:11 PM	35	1268.50	XCSE
GENMAB A/S	14-Apr-2025	2:10:11 PM	8	1268.50	XCSE
GENMAB A/S	14-Apr-2025	2:10:11 PM	31	1268.50	XCSE
GENMAB A/S	14-Apr-2025	2:10:14 PM	5	1268.50	CEUX
GENMAB A/S	14-Apr-2025	2:10:14 PM	5	1268.50	CEUX
GENMAB A/S	14-Apr-2025	2:10:14 PM	6	1268.50	CEUX
GENMAB A/S	14-Apr-2025	2:10:23 PM	10	1268.00	AQEU
GENMAB A/S	14-Apr-2025	2:11:05 PM	12	1268.00	AQEU
GENMAB A/S	14-Apr-2025	2:11:05 PM	14	1268.00	AQEU
GENMAB A/S	14-Apr-2025	2:11:11 PM	8	1268.00	AQEU
GENMAB A/S	14-Apr-2025	2:11:12 PM	66	1268.00	XCSE
GENMAB A/S	14-Apr-2025	2:11:12 PM	3	1267.50	XCSE
GENMAB A/S	14-Apr-2025	2:12:09 PM	20	1267.50	CEUX
GENMAB A/S	14-Apr-2025	2:12:09 PM	65	1267.00	CEUX
GENMAB A/S	14-Apr-2025	2:12:14 PM	35	1267.50	XCSE
GENMAB A/S	14-Apr-2025	2:12:14 PM	15	1267.50	XCSE

Exhibit 99.1(a)

APPENDIX Share buy-back programme - Specification for April 14 – April 18, 2025

GENMAB A/S	14-Apr-2025	2:12:14 PM	48	1267.50	XCSE
GENMAB A/S	14-Apr-2025	2:13:05 PM	38	1267.50	XCSE
GENMAB A/S	14-Apr-2025	2:13:05 PM	20	1267.00	CEUX
GENMAB A/S	14-Apr-2025	2:13:16 PM	15	1267.00	AQEU
GENMAB A/S	14-Apr-2025	2:13:50 PM	43	1268.00	XCSE
GENMAB A/S	14-Apr-2025	2:13:50 PM	7	1268.00	XCSE
GENMAB A/S	14-Apr-2025	2:13:50 PM	43	1268.00	XCSE
GENMAB A/S	14-Apr-2025	2:13:50 PM	19	1268.00	XCSE
GENMAB A/S	14-Apr-2025	2:13:50 PM	36	1268.00	CEUX
GENMAB A/S	14-Apr-2025	2:13:50 PM	5	1268.00	CEUX
GENMAB A/S	14-Apr-2025	2:13:50 PM	6	1268.00	CEUX
GENMAB A/S	14-Apr-2025	2:13:50 PM	6	1268.00	CEUX
GENMAB A/S	14-Apr-2025	2:14:01 PM	87	1267.50	XCSE
GENMAB A/S	14-Apr-2025	2:14:01 PM	9	1267.50	TQEX
GENMAB A/S	14-Apr-2025	2:14:01 PM	14	1267.50	TQEX
GENMAB A/S	14-Apr-2025	2:14:01 PM	16	1267.50	TQEX
GENMAB A/S	14-Apr-2025	2:14:01 PM	33	1268.00	AQEU
GENMAB A/S	14-Apr-2025	2:14:01 PM	25	1267.50	CEUX
GENMAB A/S	14-Apr-2025	2:16:22 PM	35	1268.50	XCSE
GENMAB A/S	14-Apr-2025	2:16:22 PM	80	1268.00	XCSE
GENMAB A/S	14-Apr-2025	2:16:22 PM	2	1268.00	XCSE
GENMAB A/S	14-Apr-2025	2:16:22 PM	35	1268.00	TQEX
GENMAB A/S	14-Apr-2025	2:16:22 PM	15	1268.00	AQEU
GENMAB A/S	14-Apr-2025	2:16:22 PM	87	1268.00	CEUX
GENMAB A/S	14-Apr-2025	2:16:29 PM	16	1268.00	AQEU
GENMAB A/S	14-Apr-2025	2:17:59 PM	33	1267.50	TQEX
GENMAB A/S	14-Apr-2025	2:18:00 PM	21	1267.50	CEUX
GENMAB A/S	14-Apr-2025	2:18:52 PM	30	1268.00	XCSE
GENMAB A/S	14-Apr-2025	2:18:52 PM	50	1268.00	XCSE
GENMAB A/S	14-Apr-2025	2:18:52 PM	30	1268.00	XCSE
GENMAB A/S	14-Apr-2025	2:18:52 PM	2	1268.00	XCSE
GENMAB A/S	14-Apr-2025	2:18:52 PM	43	1268.00	XCSE
GENMAB A/S	14-Apr-2025	2:18:52 PM	43	1268.00	XCSE
GENMAB A/S	14-Apr-2025	2:18:52 PM	10	1267.50	TQEX
GENMAB A/S	14-Apr-2025	2:19:20 PM	19	1268.00	XCSE
GENMAB A/S	14-Apr-2025	2:19:51 PM	10	1269.00	XCSE
GENMAB A/S	14-Apr-2025	2:19:51 PM	47	1269.00	XCSE
GENMAB A/S	14-Apr-2025	2:19:51 PM	5	1269.00	XCSE
GENMAB A/S	14-Apr-2025	2:21:37 PM	31	1269.50	XCSE
GENMAB A/S	14-Apr-2025	2:21:44 PM	45	1270.00	XCSE
GENMAB A/S	14-Apr-2025	2:21:44 PM	7	1270.00	XCSE
GENMAB A/S	14-Apr-2025	2:21:44 PM	60	1270.00	XCSE
GENMAB A/S	14-Apr-2025	2:21:44 PM	33	1270.00	CEUX

Exhibit 99.1(a)

APPENDIX Share buy-back programme - Specification for April 14 – April 18, 2025

GENMAB A/S	14-Apr-2025	2:21:44 PM	44	1270.00	CEUX
GENMAB A/S	14-Apr-2025	2:21:44 PM	35	1270.00	CEUX
GENMAB A/S	14-Apr-2025	2:21:56 PM	17	1270.00	CEUX
GENMAB A/S	14-Apr-2025	2:22:34 PM	9	1270.50	CEUX
GENMAB A/S	14-Apr-2025	2:22:38 PM	36	1270.50	CEUX
GENMAB A/S	14-Apr-2025	2:22:38 PM	5	1270.50	CEUX
GENMAB A/S	14-Apr-2025	2:22:40 PM	36	1270.50	CEUX
GENMAB A/S	14-Apr-2025	2:22:40 PM	6	1270.50	CEUX
GENMAB A/S	14-Apr-2025	2:23:42 PM	67	1270.50	XCSE
GENMAB A/S	14-Apr-2025	2:23:44 PM	2	1270.50	CEUX
GENMAB A/S	14-Apr-2025	2:23:46 PM	62	1270.50	XCSE
GENMAB A/S	14-Apr-2025	2:23:46 PM	21	1270.50	XCSE
GENMAB A/S	14-Apr-2025	2:24:00 PM	10	1271.00	XCSE
GENMAB A/S	14-Apr-2025	2:24:00 PM	41	1271.00	XCSE
GENMAB A/S	14-Apr-2025	2:24:00 PM	43	1271.00	XCSE
GENMAB A/S	14-Apr-2025	2:24:00 PM	18	1271.00	XCSE
GENMAB A/S	14-Apr-2025	2:24:49 PM	85	1270.50	CEUX
GENMAB A/S	14-Apr-2025	2:26:49 PM	89	1271.00	XCSE
GENMAB A/S	14-Apr-2025	2:26:49 PM	112	1271.00	XCSE
GENMAB A/S	14-Apr-2025	2:26:49 PM	57	1269.50	XCSE
GENMAB A/S	14-Apr-2025	2:26:49 PM	30	1271.00	TQEX
GENMAB A/S	14-Apr-2025	2:26:49 PM	25	1270.00	TQEX
GENMAB A/S	14-Apr-2025	2:26:49 PM	36	1271.00	AQEU
GENMAB A/S	14-Apr-2025	2:26:49 PM	40	1270.00	AQEU
GENMAB A/S	14-Apr-2025	2:26:49 PM	84	1271.00	CEUX
GENMAB A/S	14-Apr-2025	2:26:49 PM	25	1271.00	CEUX
GENMAB A/S	14-Apr-2025	2:26:49 PM	25	1270.00	CEUX
GENMAB A/S	14-Apr-2025	2:26:51 PM	18	1269.50	CEUX
GENMAB A/S	14-Apr-2025	2:27:26 PM	1	1269.50	XCSE
GENMAB A/S	14-Apr-2025	2:27:26 PM	69	1269.50	CEUX
GENMAB A/S	14-Apr-2025	2:28:52 PM	42	1270.00	XCSE
GENMAB A/S	14-Apr-2025	2:28:52 PM	84	1269.50	XCSE
GENMAB A/S	14-Apr-2025	2:29:13 PM	76	1269.50	CEUX
GENMAB A/S	14-Apr-2025	2:32:19 PM	87	1271.00	XCSE
GENMAB A/S	14-Apr-2025	2:32:19 PM	54	1271.50	XCSE
GENMAB A/S	14-Apr-2025	2:32:19 PM	10	1271.50	XCSE
GENMAB A/S	14-Apr-2025	2:32:19 PM	35	1271.50	XCSE
GENMAB A/S	14-Apr-2025	2:32:19 PM	13	1271.50	XCSE
GENMAB A/S	14-Apr-2025	2:32:19 PM	49	1271.50	XCSE
GENMAB A/S	14-Apr-2025	2:32:19 PM	12	1271.50	XCSE
GENMAB A/S	14-Apr-2025	2:32:19 PM	51	1271.50	XCSE
GENMAB A/S	14-Apr-2025	2:32:19 PM	7	1271.00	TQEX
GENMAB A/S	14-Apr-2025	2:32:19 PM	5	1271.00	TQEX

Exhibit 99.1(a)

APPENDIX Share buy-back programme - Specification for April 14 – April 18, 2025

GENMAB A/S	14-Apr-2025	2:32:19 PM	22	1271.00	TQEX
GENMAB A/S	14-Apr-2025	2:32:19 PM	84	1271.50	CEUX
GENMAB A/S	14-Apr-2025	2:32:19 PM	4	1271.50	CEUX
GENMAB A/S	14-Apr-2025	2:32:32 PM	9	1271.00	AQEU
GENMAB A/S	14-Apr-2025	2:32:44 PM	18	1271.00	AQEU
GENMAB A/S	14-Apr-2025	2:33:10 PM	54	1271.50	XCSE
GENMAB A/S	14-Apr-2025	2:33:10 PM	10	1271.50	XCSE
GENMAB A/S	14-Apr-2025	2:36:33 PM	13	1272.50	XCSE
GENMAB A/S	14-Apr-2025	2:36:33 PM	54	1272.50	XCSE
GENMAB A/S	14-Apr-2025	2:36:33 PM	11	1272.50	CEUX
GENMAB A/S	14-Apr-2025	2:36:33 PM	28	1272.50	CEUX
GENMAB A/S	14-Apr-2025	2:38:04 PM	48	1274.50	XCSE
GENMAB A/S	14-Apr-2025	2:38:23 PM	48	1274.50	XCSE
GENMAB A/S	14-Apr-2025	2:38:23 PM	36	1274.50	CEUX
GENMAB A/S	14-Apr-2025	2:38:25 PM	48	1274.50	XCSE
GENMAB A/S	14-Apr-2025	2:38:26 PM	48	1274.50	XCSE
GENMAB A/S	14-Apr-2025	2:38:26 PM	48	1274.50	XCSE
GENMAB A/S	14-Apr-2025	2:38:26 PM	14	1274.50	CEUX
GENMAB A/S	14-Apr-2025	2:38:27 PM	48	1274.50	XCSE
GENMAB A/S	14-Apr-2025	2:40:36 PM	85	1273.50	XCSE
GENMAB A/S	14-Apr-2025	2:40:36 PM	45	1274.00	XCSE
GENMAB A/S	14-Apr-2025	2:40:36 PM	54	1274.00	XCSE
GENMAB A/S	14-Apr-2025	2:40:36 PM	19	1273.50	TQEX
GENMAB A/S	14-Apr-2025	2:40:36 PM	9	1273.50	TQEX
GENMAB A/S	14-Apr-2025	2:40:36 PM	8	1273.50	TQEX
GENMAB A/S	14-Apr-2025	2:40:37 PM	48	1274.00	XCSE
GENMAB A/S	14-Apr-2025	2:40:37 PM	54	1274.00	XCSE
GENMAB A/S	14-Apr-2025	2:40:37 PM	10	1274.00	XCSE
GENMAB A/S	14-Apr-2025	2:40:37 PM	61	1273.50	XCSE
GENMAB A/S	14-Apr-2025	2:40:37 PM	22	1273.50	XCSE
GENMAB A/S	14-Apr-2025	2:40:41 PM	85	1273.00	CEUX
GENMAB A/S	14-Apr-2025	2:40:47 PM	1	1272.50	AQEU
GENMAB A/S	14-Apr-2025	2:42:03 PM	38	1273.00	XCSE
GENMAB A/S	14-Apr-2025	2:42:03 PM	54	1273.00	XCSE
GENMAB A/S	14-Apr-2025	2:42:03 PM	84	1272.50	XCSE
GENMAB A/S	14-Apr-2025	2:42:03 PM	5	1272.50	TQEX
GENMAB A/S	14-Apr-2025	2:42:03 PM	30	1272.50	TQEX
GENMAB A/S	14-Apr-2025	2:42:03 PM	14	1272.50	AQEU
GENMAB A/S	14-Apr-2025	2:42:10 PM	21	1272.50	AQEU
GENMAB A/S	14-Apr-2025	2:42:10 PM	2	1272.50	AQEU
GENMAB A/S	14-Apr-2025	2:42:20 PM	84	1272.00	XCSE
GENMAB A/S	14-Apr-2025	2:42:20 PM	36	1272.50	CEUX
GENMAB A/S	14-Apr-2025	2:42:20 PM	88	1272.00	CEUX

Exhibit 99.1(a)

APPENDIX Share buy-back programme - Specification for April 14 – April 18, 2025

GENMAB A/S	14-Apr-2025	2:43:03 PM	36	1272.00	CEUX
GENMAB A/S	14-Apr-2025	2:43:53 PM	82	1271.00	XCSE
GENMAB A/S	14-Apr-2025	2:43:53 PM	5	1271.00	XCSE
GENMAB A/S	14-Apr-2025	2:43:53 PM	25	1271.00	TQEX
GENMAB A/S	14-Apr-2025	2:43:53 PM	24	1271.00	AQEU
GENMAB A/S	14-Apr-2025	2:43:53 PM	36	1271.50	CEUX
GENMAB A/S	14-Apr-2025	2:43:54 PM	16	1271.50	CEUX
GENMAB A/S	14-Apr-2025	2:43:54 PM	6	1271.50	CEUX
GENMAB A/S	14-Apr-2025	2:43:58 PM	12	1271.50	CEUX
GENMAB A/S	14-Apr-2025	2:43:59 PM	11	1271.50	CEUX
GENMAB A/S	14-Apr-2025	2:43:59 PM	12	1271.50	CEUX
GENMAB A/S	14-Apr-2025	2:46:13 PM	12	1272.00	XCSE
GENMAB A/S	14-Apr-2025	2:46:13 PM	34	1271.50	XCSE
GENMAB A/S	14-Apr-2025	2:46:13 PM	47	1271.50	CEUX
GENMAB A/S	14-Apr-2025	2:46:13 PM	23	1271.50	CEUX
GENMAB A/S	14-Apr-2025	2:46:37 PM	51	1271.50	XCSE
GENMAB A/S	14-Apr-2025	2:46:37 PM	1	1271.50	CEUX
GENMAB A/S	14-Apr-2025	2:48:13 PM	40	1272.50	XCSE
GENMAB A/S	14-Apr-2025	2:48:13 PM	35	1272.50	XCSE
GENMAB A/S	14-Apr-2025	2:48:13 PM	19	1272.50	XCSE
GENMAB A/S	14-Apr-2025	2:48:13 PM	13	1271.50	CEUX
GENMAB A/S	14-Apr-2025	2:48:17 PM	12	1272.50	XCSE
GENMAB A/S	14-Apr-2025	2:48:17 PM	10	1272.50	XCSE
GENMAB A/S	14-Apr-2025	2:48:17 PM	40	1272.50	XCSE
GENMAB A/S	14-Apr-2025	2:48:17 PM	35	1272.50	XCSE
GENMAB A/S	14-Apr-2025	2:48:17 PM	41	1272.00	AQEU
GENMAB A/S	14-Apr-2025	2:48:18 PM	36	1272.00	CEUX
GENMAB A/S	14-Apr-2025	2:48:18 PM	6	1272.00	CEUX
GENMAB A/S	14-Apr-2025	2:48:18 PM	48	1272.00	CEUX
GENMAB A/S	14-Apr-2025	2:48:18 PM	70	1271.50	CEUX
GENMAB A/S	14-Apr-2025	2:48:18 PM	13	1271.50	CEUX
GENMAB A/S	14-Apr-2025	2:48:30 PM	10	1272.00	XCSE
GENMAB A/S	14-Apr-2025	2:48:30 PM	40	1272.00	XCSE
GENMAB A/S	14-Apr-2025	2:48:30 PM	13	1272.00	XCSE
GENMAB A/S	14-Apr-2025	2:48:30 PM	47	1272.50	XCSE
GENMAB A/S	14-Apr-2025	2:48:30 PM	2	1272.50	XCSE
GENMAB A/S	14-Apr-2025	2:48:30 PM	17	1271.50	CEUX
GENMAB A/S	14-Apr-2025	2:48:30 PM	8	1271.50	CEUX
GENMAB A/S	14-Apr-2025	2:48:30 PM	62	1271.50	CEUX
GENMAB A/S	14-Apr-2025	2:49:30 PM	9	1272.00	XCSE
GENMAB A/S	14-Apr-2025	2:49:30 PM	40	1272.00	XCSE
GENMAB A/S	14-Apr-2025	2:49:30 PM	10	1272.00	XCSE
GENMAB A/S	14-Apr-2025	2:49:30 PM	13	1272.00	XCSE

Exhibit 99.1(a)

APPENDIX Share buy-back programme - Specification for April 14 – April 18, 2025

GENMAB A/S	14-Apr-2025	2:49:30 PM	35	1272.00	XCSE
GENMAB A/S	14-Apr-2025	2:49:31 PM	5	1272.00	CEUX
GENMAB A/S	14-Apr-2025	2:49:31 PM	5	1272.00	CEUX
GENMAB A/S	14-Apr-2025	2:49:31 PM	5	1272.00	CEUX
GENMAB A/S	14-Apr-2025	2:49:31 PM	5	1272.00	CEUX
GENMAB A/S	14-Apr-2025	2:49:32 PM	11	1272.00	CEUX
GENMAB A/S	14-Apr-2025	2:51:23 PM	40	1272.00	XCSE
GENMAB A/S	14-Apr-2025	2:51:23 PM	13	1272.00	XCSE
GENMAB A/S	14-Apr-2025	2:51:23 PM	59	1272.00	XCSE
GENMAB A/S	14-Apr-2025	2:51:23 PM	89	1271.50	CEUX
GENMAB A/S	14-Apr-2025	2:51:23 PM	86	1271.50	CEUX
GENMAB A/S	14-Apr-2025	2:52:49 PM	85	1271.00	XCSE
GENMAB A/S	14-Apr-2025	2:53:51 PM	2	1271.00	TQEX
GENMAB A/S	14-Apr-2025	2:53:51 PM	29	1271.00	TQEX
GENMAB A/S	14-Apr-2025	2:53:51 PM	4	1271.00	TQEX
GENMAB A/S	14-Apr-2025	2:53:51 PM	14	1271.00	AQEU
GENMAB A/S	14-Apr-2025	2:53:55 PM	35	1271.00	XCSE
GENMAB A/S	14-Apr-2025	2:53:55 PM	13	1271.00	XCSE
GENMAB A/S	14-Apr-2025	2:53:55 PM	40	1271.00	XCSE
GENMAB A/S	14-Apr-2025	2:53:55 PM	10	1271.00	XCSE
GENMAB A/S	14-Apr-2025	2:53:55 PM	11	1271.00	XCSE
GENMAB A/S	14-Apr-2025	2:53:55 PM	3	1271.00	XCSE
GENMAB A/S	14-Apr-2025	2:53:55 PM	18	1270.50	CEUX
GENMAB A/S	14-Apr-2025	2:53:55 PM	2	1270.50	CEUX
GENMAB A/S	14-Apr-2025	2:53:55 PM	62	1270.50	CEUX
GENMAB A/S	14-Apr-2025	2:53:56 PM	9	1271.00	XCSE
GENMAB A/S	14-Apr-2025	2:53:56 PM	41	1271.00	XCSE
GENMAB A/S	14-Apr-2025	2:53:56 PM	3	1271.00	XCSE
GENMAB A/S	14-Apr-2025	2:53:56 PM	10	1271.00	XCSE
GENMAB A/S	14-Apr-2025	2:53:56 PM	38	1271.00	XCSE
GENMAB A/S	14-Apr-2025	2:53:56 PM	7	1270.50	CEUX
GENMAB A/S	14-Apr-2025	2:54:00 PM	46	1270.00	XCSE
GENMAB A/S	14-Apr-2025	2:54:00 PM	41	1270.00	XCSE
GENMAB A/S	14-Apr-2025	2:54:00 PM	28	1270.00	TQEX
GENMAB A/S	14-Apr-2025	2:54:01 PM	5	1270.00	TQEX
GENMAB A/S	14-Apr-2025	2:54:01 PM	25	1270.00	AQEU
GENMAB A/S	14-Apr-2025	2:54:02 PM	84	1269.50	CEUX
GENMAB A/S	14-Apr-2025	2:54:20 PM	25	1269.50	TQEX
GENMAB A/S	14-Apr-2025	2:55:56 PM	17	1270.50	XCSE
GENMAB A/S	14-Apr-2025	2:55:56 PM	13	1270.50	XCSE
GENMAB A/S	14-Apr-2025	2:55:56 PM	11	1270.50	XCSE
GENMAB A/S	14-Apr-2025	2:56:08 PM	12	1270.50	XCSE
GENMAB A/S	14-Apr-2025	2:56:09 PM	11	1270.50	XCSE

Exhibit 99.1(a)

APPENDIX Share buy-back programme - Specification for April 14 – April 18, 2025

GENMAB A/S	14-Apr-2025	2:56:09 PM	13	1270.50	XCSE
GENMAB A/S	14-Apr-2025	2:56:20 PM	13	1270.50	XCSE
GENMAB A/S	14-Apr-2025	2:56:20 PM	11	1270.50	XCSE
GENMAB A/S	14-Apr-2025	2:56:21 PM	11	1270.50	XCSE
GENMAB A/S	14-Apr-2025	2:57:05 PM	21	1270.50	XCSE
GENMAB A/S	14-Apr-2025	2:57:09 PM	43	1270.50	XCSE
GENMAB A/S	14-Apr-2025	2:57:09 PM	18	1270.50	XCSE
GENMAB A/S	14-Apr-2025	2:57:34 PM	35	1270.50	XCSE
GENMAB A/S	14-Apr-2025	2:57:34 PM	39	1270.50	XCSE
GENMAB A/S	14-Apr-2025	2:57:34 PM	36	1270.50	CEUX
GENMAB A/S	14-Apr-2025	2:57:34 PM	6	1270.50	CEUX
GENMAB A/S	14-Apr-2025	2:57:34 PM	6	1270.50	CEUX
GENMAB A/S	14-Apr-2025	2:58:20 PM	47	1270.50	XCSE
GENMAB A/S	14-Apr-2025	2:58:59 PM	6	1271.00	CEUX
GENMAB A/S	14-Apr-2025	2:58:59 PM	6	1271.00	CEUX
GENMAB A/S	14-Apr-2025	2:59:03 PM	11	1271.00	XCSE
GENMAB A/S	14-Apr-2025	2:59:03 PM	13	1271.00	XCSE
GENMAB A/S	14-Apr-2025	2:59:05 PM	22	1270.50	AQEU
GENMAB A/S	14-Apr-2025	2:59:10 PM	10	1271.00	XCSE
GENMAB A/S	14-Apr-2025	2:59:10 PM	40	1271.00	XCSE
GENMAB A/S	14-Apr-2025	2:59:10 PM	10	1271.00	XCSE
GENMAB A/S	14-Apr-2025	2:59:10 PM	12	1271.00	XCSE
GENMAB A/S	14-Apr-2025	2:59:43 PM	24	1270.50	AQEU
GENMAB A/S	14-Apr-2025	2:59:50 PM	10	1271.00	XCSE
GENMAB A/S	14-Apr-2025	2:59:50 PM	12	1271.00	XCSE
GENMAB A/S	14-Apr-2025	2:59:50 PM	40	1271.00	XCSE
GENMAB A/S	14-Apr-2025	2:59:50 PM	13	1271.00	XCSE
GENMAB A/S	14-Apr-2025	2:59:50 PM	35	1271.00	XCSE
GENMAB A/S	14-Apr-2025	2:59:50 PM	2	1271.00	XCSE
GENMAB A/S	14-Apr-2025	3:00:07 PM	36	1270.50	CEUX
GENMAB A/S	14-Apr-2025	3:00:07 PM	60	1270.00	CEUX
GENMAB A/S	14-Apr-2025	3:00:07 PM	28	1270.00	CEUX
GENMAB A/S	14-Apr-2025	3:00:08 PM	8	1270.00	CEUX
GENMAB A/S	14-Apr-2025	3:00:08 PM	2	1270.00	CEUX
GENMAB A/S	14-Apr-2025	3:00:08 PM	15	1270.00	CEUX
GENMAB A/S	14-Apr-2025	3:01:08 PM	25	1269.50	XCSE
GENMAB A/S	14-Apr-2025	3:01:08 PM	58	1269.50	XCSE
GENMAB A/S	14-Apr-2025	3:01:08 PM	2	1269.50	TQEX
GENMAB A/S	14-Apr-2025	3:01:08 PM	8	1269.50	TQEX
GENMAB A/S	14-Apr-2025	3:01:08 PM	21	1269.50	AQEU
GENMAB A/S	14-Apr-2025	3:01:08 PM	18	1269.50	AQEU
GENMAB A/S	14-Apr-2025	3:01:08 PM	20	1269.50	CEUX
GENMAB A/S	14-Apr-2025	3:01:08 PM	36	1270.00	CEUX

Exhibit 99.1(a)

APPENDIX Share buy-back programme - Specification for April 14 – April 18, 2025

GENMAB A/S	14-Apr-2025	3:02:18 PM	20	1270.00	CEUX
GENMAB A/S	14-Apr-2025	3:03:32 PM	16	1270.00	CEUX
GENMAB A/S	14-Apr-2025	3:03:32 PM	50	1270.00	CEUX
GENMAB A/S	14-Apr-2025	3:04:13 PM	35	1269.50	XCSE
GENMAB A/S	14-Apr-2025	3:04:13 PM	19	1269.50	XCSE
GENMAB A/S	14-Apr-2025	3:04:13 PM	40	1270.00	XCSE
GENMAB A/S	14-Apr-2025	3:04:13 PM	18	1270.00	XCSE
GENMAB A/S	14-Apr-2025	3:04:13 PM	84	1268.50	XCSE
GENMAB A/S	14-Apr-2025	3:04:13 PM	47	1268.50	XCSE
GENMAB A/S	14-Apr-2025	3:04:13 PM	40	1268.50	XCSE
GENMAB A/S	14-Apr-2025	3:04:13 PM	25	1268.50	XCSE
GENMAB A/S	14-Apr-2025	3:04:13 PM	49	1269.50	TQEX
GENMAB A/S	14-Apr-2025	3:04:13 PM	25	1268.50	TQEX
GENMAB A/S	14-Apr-2025	3:04:13 PM	37	1269.50	AQEU
GENMAB A/S	14-Apr-2025	3:04:13 PM	33	1268.50	AQEU
GENMAB A/S	14-Apr-2025	3:04:13 PM	59	1269.00	CEUX
GENMAB A/S	14-Apr-2025	3:04:13 PM	23	1269.00	CEUX
GENMAB A/S	14-Apr-2025	3:04:13 PM	89	1268.00	CEUX
GENMAB A/S	14-Apr-2025	3:04:15 PM	12	1267.00	CEUX
GENMAB A/S	14-Apr-2025	3:04:37 PM	34	1267.00	CEUX
GENMAB A/S	14-Apr-2025	3:04:47 PM	5	1267.00	CEUX
GENMAB A/S	14-Apr-2025	3:05:19 PM	23	1267.50	AQEU
GENMAB A/S	14-Apr-2025	3:05:20 PM	7	1268.00	XCSE
GENMAB A/S	14-Apr-2025	3:05:20 PM	11	1268.00	XCSE
GENMAB A/S	14-Apr-2025	3:05:20 PM	7	1268.00	XCSE
GENMAB A/S	14-Apr-2025	3:05:20 PM	40	1268.00	XCSE
GENMAB A/S	14-Apr-2025	3:05:20 PM	11	1268.00	XCSE
GENMAB A/S	14-Apr-2025	3:05:20 PM	12	1268.00	XCSE
GENMAB A/S	14-Apr-2025	3:07:23 PM	31	1267.00	CEUX
GENMAB A/S	14-Apr-2025	3:07:24 PM	13	1269.00	XCSE
GENMAB A/S	14-Apr-2025	3:07:24 PM	73	1269.00	XCSE
GENMAB A/S	14-Apr-2025	3:07:43 PM	40	1269.00	XCSE
GENMAB A/S	14-Apr-2025	3:07:43 PM	11	1269.00	XCSE
GENMAB A/S	14-Apr-2025	3:07:43 PM	12	1269.00	XCSE
GENMAB A/S	14-Apr-2025	3:07:43 PM	11	1269.00	XCSE
GENMAB A/S	14-Apr-2025	3:07:43 PM	12	1269.00	XCSE
GENMAB A/S	14-Apr-2025	3:08:28 PM	13	1269.00	XCSE
GENMAB A/S	14-Apr-2025	3:09:09 PM	3	1268.00	XCSE
GENMAB A/S	14-Apr-2025	3:09:38 PM	29	1269.00	CEUX
GENMAB A/S	14-Apr-2025	3:10:10 PM	14	1270.00	XCSE
GENMAB A/S	14-Apr-2025	3:10:10 PM	40	1270.00	XCSE
GENMAB A/S	14-Apr-2025	3:10:10 PM	40	1270.00	XCSE
GENMAB A/S	14-Apr-2025	3:10:10 PM	13	1270.00	XCSE

Exhibit 99.1(a)

APPENDIX Share buy-back programme - Specification for April 14 – April 18, 2025

GENMAB A/S	14-Apr-2025	3:10:11 PM	11	1270.00	XCSE
GENMAB A/S	14-Apr-2025	3:10:11 PM	12	1270.00	XCSE
GENMAB A/S	14-Apr-2025	3:10:11 PM	10	1270.00	XCSE
GENMAB A/S	14-Apr-2025	3:10:11 PM	10	1270.00	XCSE
GENMAB A/S	14-Apr-2025	3:10:24 PM	11	1270.50	XCSE
GENMAB A/S	14-Apr-2025	3:10:24 PM	10	1270.50	XCSE
GENMAB A/S	14-Apr-2025	3:10:24 PM	13	1270.50	XCSE
GENMAB A/S	14-Apr-2025	3:10:24 PM	11	1270.50	XCSE
GENMAB A/S	14-Apr-2025	3:10:24 PM	40	1270.50	XCSE
GENMAB A/S	14-Apr-2025	3:10:24 PM	10	1270.50	XCSE
GENMAB A/S	14-Apr-2025	3:10:24 PM	13	1270.50	XCSE
GENMAB A/S	14-Apr-2025	3:10:31 PM	12	1270.50	XCSE
GENMAB A/S	14-Apr-2025	3:10:31 PM	40	1270.50	XCSE
GENMAB A/S	14-Apr-2025	3:10:31 PM	84	1270.00	XCSE
GENMAB A/S	14-Apr-2025	3:10:38 PM	36	1270.50	CEUX
GENMAB A/S	14-Apr-2025	3:10:53 PM	27	1270.00	AQEU
GENMAB A/S	14-Apr-2025	3:11:15 PM	41	1271.00	CEUX
GENMAB A/S	14-Apr-2025	3:11:15 PM	21	1271.00	CEUX
GENMAB A/S	14-Apr-2025	3:11:15 PM	13	1271.00	CEUX
GENMAB A/S	14-Apr-2025	3:11:40 PM	50	1271.50	XCSE
GENMAB A/S	14-Apr-2025	3:11:40 PM	12	1271.50	XCSE
GENMAB A/S	14-Apr-2025	3:11:40 PM	13	1271.50	XCSE
GENMAB A/S	14-Apr-2025	3:11:40 PM	10	1271.50	XCSE
GENMAB A/S	14-Apr-2025	3:11:40 PM	11	1271.50	XCSE
GENMAB A/S	14-Apr-2025	3:11:40 PM	16	1271.50	XCSE
GENMAB A/S	14-Apr-2025	3:11:40 PM	34	1271.00	XCSE
GENMAB A/S	14-Apr-2025	3:11:40 PM	1	1271.00	XCSE
GENMAB A/S	14-Apr-2025	3:11:40 PM	50	1271.00	XCSE
GENMAB A/S	14-Apr-2025	3:12:40 PM	21	1270.50	AQEU
GENMAB A/S	14-Apr-2025	3:12:40 PM	36	1271.00	CEUX
GENMAB A/S	14-Apr-2025	3:12:45 PM	33	1270.50	TQEX
GENMAB A/S	14-Apr-2025	3:12:46 PM	10	1270.50	TQEX
GENMAB A/S	14-Apr-2025	3:14:31 PM	72	1270.00	XCSE
GENMAB A/S	14-Apr-2025	3:14:31 PM	2	1270.50	TQEX
GENMAB A/S	14-Apr-2025	3:14:40 PM	16	1270.00	XCSE
GENMAB A/S	14-Apr-2025	3:14:40 PM	19	1270.50	CEUX
GENMAB A/S	14-Apr-2025	3:14:40 PM	86	1270.00	CEUX
GENMAB A/S	14-Apr-2025	3:15:24 PM	112	1270.00	XCSE
GENMAB A/S	14-Apr-2025	3:15:24 PM	36	1270.00	CEUX
GENMAB A/S	14-Apr-2025	3:15:24 PM	9	1270.00	CEUX
GENMAB A/S	14-Apr-2025	3:15:30 PM	60	1270.00	XCSE
GENMAB A/S	14-Apr-2025	3:15:30 PM	27	1270.00	XCSE
GENMAB A/S	14-Apr-2025	3:15:33 PM	36	1270.00	AQEU

Exhibit 99.1(a)

APPENDIX Share buy-back programme - Specification for April 14 – April 18, 2025

GENMAB A/S	14-Apr-2025	3:15:59 PM	85	1269.00	XCSE
GENMAB A/S	14-Apr-2025	3:19:19 PM	40	1272.50	XCSE
GENMAB A/S	14-Apr-2025	3:19:27 PM	28	1273.00	CEUX
GENMAB A/S	14-Apr-2025	3:19:28 PM	1	1273.00	CEUX
GENMAB A/S	14-Apr-2025	3:20:01 PM	42	1273.50	XCSE
GENMAB A/S	14-Apr-2025	3:20:17 PM	45	1273.50	XCSE
GENMAB A/S	14-Apr-2025	3:20:49 PM	32	1273.00	XCSE
GENMAB A/S	14-Apr-2025	3:20:49 PM	49	1273.00	XCSE
GENMAB A/S	14-Apr-2025	3:20:49 PM	21	1273.00	XCSE
GENMAB A/S	14-Apr-2025	3:20:49 PM	32	1273.00	XCSE
GENMAB A/S	14-Apr-2025	3:20:49 PM	71	1273.00	TQEX
GENMAB A/S	14-Apr-2025	3:20:49 PM	25	1273.00	AQEU
GENMAB A/S	14-Apr-2025	3:20:49 PM	84	1273.00	CEUX
GENMAB A/S	14-Apr-2025	3:20:49 PM	36	1273.00	CEUX
GENMAB A/S	14-Apr-2025	3:20:49 PM	30	1273.50	CEUX
GENMAB A/S	14-Apr-2025	3:20:53 PM	32	1273.00	XCSE
GENMAB A/S	14-Apr-2025	3:20:53 PM	22	1273.00	XCSE
GENMAB A/S	14-Apr-2025	3:20:53 PM	40	1273.00	XCSE
GENMAB A/S	14-Apr-2025	3:20:53 PM	44	1272.50	XCSE
GENMAB A/S	14-Apr-2025	3:20:53 PM	36	1273.00	CEUX
GENMAB A/S	14-Apr-2025	3:22:14 PM	10	1273.50	XCSE
GENMAB A/S	14-Apr-2025	3:22:14 PM	40	1273.50	XCSE
GENMAB A/S	14-Apr-2025	3:22:14 PM	13	1273.50	XCSE
GENMAB A/S	14-Apr-2025	3:22:14 PM	35	1273.50	XCSE
GENMAB A/S	14-Apr-2025	3:22:14 PM	14	1273.50	XCSE
GENMAB A/S	14-Apr-2025	3:22:15 PM	12	1273.50	XCSE
GENMAB A/S	14-Apr-2025	3:22:15 PM	13	1273.50	XCSE
GENMAB A/S	14-Apr-2025	3:22:15 PM	40	1273.50	XCSE
GENMAB A/S	14-Apr-2025	3:22:15 PM	12	1273.50	XCSE
GENMAB A/S	14-Apr-2025	3:22:15 PM	11	1273.50	XCSE
GENMAB A/S	14-Apr-2025	3:22:15 PM	12	1273.50	XCSE
GENMAB A/S	14-Apr-2025	3:22:15 PM	35	1273.50	XCSE
GENMAB A/S	14-Apr-2025	3:22:15 PM	2	1273.50	XCSE
GENMAB A/S	14-Apr-2025	3:22:16 PM	11	1273.50	XCSE
GENMAB A/S	14-Apr-2025	3:22:16 PM	40	1273.50	XCSE
GENMAB A/S	14-Apr-2025	3:22:18 PM	40	1273.50	XCSE
GENMAB A/S	14-Apr-2025	3:22:18 PM	12	1273.50	XCSE
GENMAB A/S	14-Apr-2025	3:22:18 PM	12	1273.50	XCSE
GENMAB A/S	14-Apr-2025	3:22:18 PM	71	1273.00	CEUX
GENMAB A/S	14-Apr-2025	3:22:18 PM	13	1273.00	CEUX
GENMAB A/S	14-Apr-2025	3:22:18 PM	5	1273.50	CEUX
GENMAB A/S	14-Apr-2025	3:22:18 PM	11	1273.50	CEUX
GENMAB A/S	14-Apr-2025	3:22:22 PM	12	1273.50	CEUX

Exhibit 99.1(a)

APPENDIX Share buy-back programme - Specification for April 14 – April 18, 2025

GENMAB A/S	14-Apr-2025	3:22:33 PM	89	1273.50	XCSE
GENMAB A/S	14-Apr-2025	3:22:33 PM	43	1273.50	XCSE
GENMAB A/S	14-Apr-2025	3:22:33 PM	38	1273.50	AQEU
GENMAB A/S	14-Apr-2025	3:22:33 PM	76	1273.50	CEUX
GENMAB A/S	14-Apr-2025	3:22:33 PM	6	1273.50	CEUX
GENMAB A/S	14-Apr-2025	3:22:33 PM	3	1273.50	CEUX
GENMAB A/S	14-Apr-2025	3:22:33 PM	10	1273.50	CEUX
GENMAB A/S	14-Apr-2025	3:22:45 PM	1	1273.50	CEUX
GENMAB A/S	14-Apr-2025	3:22:46 PM	1	1273.50	CEUX
GENMAB A/S	14-Apr-2025	3:22:50 PM	5	1273.50	XCSE
GENMAB A/S	14-Apr-2025	3:23:23 PM	10	1274.00	XCSE
GENMAB A/S	14-Apr-2025	3:23:23 PM	13	1274.00	XCSE
GENMAB A/S	14-Apr-2025	3:23:23 PM	11	1274.00	XCSE
GENMAB A/S	14-Apr-2025	3:23:24 PM	10	1274.00	XCSE
GENMAB A/S	14-Apr-2025	3:23:43 PM	78	1273.50	XCSE
GENMAB A/S	14-Apr-2025	3:23:43 PM	8	1273.50	XCSE
GENMAB A/S	14-Apr-2025	3:23:43 PM	50	1273.50	CEUX
GENMAB A/S	14-Apr-2025	3:23:43 PM	22	1273.50	CEUX
GENMAB A/S	14-Apr-2025	3:23:43 PM	8	1273.50	CEUX
GENMAB A/S	14-Apr-2025	3:23:43 PM	4	1273.50	CEUX
GENMAB A/S	14-Apr-2025	3:23:56 PM	30	1273.50	XCSE
GENMAB A/S	14-Apr-2025	3:23:56 PM	11	1273.50	XCSE
GENMAB A/S	14-Apr-2025	3:23:56 PM	9	1273.50	CEUX
GENMAB A/S	14-Apr-2025	3:23:56 PM	47	1273.50	CEUX
GENMAB A/S	14-Apr-2025	3:23:57 PM	43	1273.50	XCSE
GENMAB A/S	14-Apr-2025	3:23:57 PM	12	1273.50	CEUX
GENMAB A/S	14-Apr-2025	3:24:07 PM	34	1273.00	TQEX
GENMAB A/S	14-Apr-2025	3:24:07 PM	9	1273.00	TQEX
GENMAB A/S	14-Apr-2025	3:24:07 PM	36	1273.50	CEUX
GENMAB A/S	14-Apr-2025	3:24:07 PM	6	1273.50	CEUX
GENMAB A/S	14-Apr-2025	3:25:29 PM	75	1272.50	XCSE
GENMAB A/S	14-Apr-2025	3:25:29 PM	10	1272.50	XCSE
GENMAB A/S	14-Apr-2025	3:25:31 PM	17	1273.00	XCSE
GENMAB A/S	14-Apr-2025	3:25:31 PM	10	1273.00	XCSE
GENMAB A/S	14-Apr-2025	3:25:31 PM	11	1273.00	XCSE
GENMAB A/S	14-Apr-2025	3:25:31 PM	16	1273.00	XCSE
GENMAB A/S	14-Apr-2025	3:25:31 PM	10	1273.00	XCSE
GENMAB A/S	14-Apr-2025	3:26:09 PM	10	1273.00	CEUX
GENMAB A/S	14-Apr-2025	3:26:09 PM	8	1273.00	CEUX
GENMAB A/S	14-Apr-2025	3:26:33 PM	1	1272.00	AQEU
GENMAB A/S	14-Apr-2025	3:26:33 PM	83	1272.00	CEUX
GENMAB A/S	14-Apr-2025	3:27:19 PM	6	1271.50	XCSE
GENMAB A/S	14-Apr-2025	3:27:19 PM	61	1272.00	TQEX

Exhibit 99.1(a)

APPENDIX Share buy-back programme - Specification for April 14 – April 18, 2025

GENMAB A/S	14-Apr-2025	3:27:21 PM	3	1272.00	AQEU
GENMAB A/S	14-Apr-2025	3:27:29 PM	1	1272.00	AQEU
GENMAB A/S	14-Apr-2025	3:27:50 PM	2	1272.00	AQEU
GENMAB A/S	14-Apr-2025	3:27:50 PM	2	1272.00	AQEU
GENMAB A/S	14-Apr-2025	3:27:50 PM	2	1272.00	AQEU
GENMAB A/S	14-Apr-2025	3:27:50 PM	2	1272.00	AQEU
GENMAB A/S	14-Apr-2025	3:27:50 PM	2	1272.00	AQEU
GENMAB A/S	14-Apr-2025	3:27:50 PM	2	1272.00	AQEU
GENMAB A/S	14-Apr-2025	3:27:50 PM	3	1272.00	AQEU
GENMAB A/S	14-Apr-2025	3:27:50 PM	8	1272.00	AQEU
GENMAB A/S	14-Apr-2025	3:28:03 PM	1	1271.50	XCSE
GENMAB A/S	14-Apr-2025	3:28:03 PM	1	1271.50	XCSE
GENMAB A/S	14-Apr-2025	3:28:03 PM	63	1271.50	XCSE
GENMAB A/S	14-Apr-2025	3:28:03 PM	36	1272.00	CEUX
GENMAB A/S	14-Apr-2025	3:28:33 PM	11	1272.50	XCSE
GENMAB A/S	14-Apr-2025	3:28:33 PM	76	1272.00	CEUX
GENMAB A/S	14-Apr-2025	3:28:33 PM	9	1272.00	CEUX
GENMAB A/S	14-Apr-2025	3:28:34 PM	26	1272.00	AQEU
GENMAB A/S	14-Apr-2025	3:28:35 PM	17	1272.00	AQEU
GENMAB A/S	14-Apr-2025	3:28:40 PM	14	1271.50	XCSE
GENMAB A/S	14-Apr-2025	3:28:40 PM	22	1272.00	XCSE
GENMAB A/S	14-Apr-2025	3:28:40 PM	40	1272.00	XCSE
GENMAB A/S	14-Apr-2025	3:28:40 PM	35	1272.00	XCSE
GENMAB A/S	14-Apr-2025	3:28:40 PM	15	1272.00	XCSE
GENMAB A/S	14-Apr-2025	3:28:40 PM	36	1272.00	CEUX
GENMAB A/S	14-Apr-2025	3:28:40 PM	5	1272.00	CEUX
GENMAB A/S	14-Apr-2025	3:28:40 PM	5	1272.00	CEUX
GENMAB A/S	14-Apr-2025	3:28:40 PM	48	1272.00	CEUX
GENMAB A/S	14-Apr-2025	3:28:41 PM	35	1272.00	XCSE
GENMAB A/S	14-Apr-2025	3:28:41 PM	40	1272.00	XCSE
GENMAB A/S	14-Apr-2025	3:28:41 PM	37	1272.00	XCSE
GENMAB A/S	14-Apr-2025	3:28:41 PM	13	1272.00	XCSE
GENMAB A/S	14-Apr-2025	3:28:41 PM	11	1272.00	XCSE
GENMAB A/S	14-Apr-2025	3:28:41 PM	13	1272.00	XCSE
GENMAB A/S	14-Apr-2025	3:28:41 PM	18	1272.00	XCSE
GENMAB A/S	14-Apr-2025	3:28:41 PM	36	1272.00	CEUX
GENMAB A/S	14-Apr-2025	3:28:41 PM	6	1272.00	CEUX
GENMAB A/S	14-Apr-2025	3:28:41 PM	5	1272.00	CEUX
GENMAB A/S	14-Apr-2025	3:28:41 PM	5	1272.00	CEUX
GENMAB A/S	14-Apr-2025	3:28:41 PM	15	1272.00	CEUX
GENMAB A/S	14-Apr-2025	3:28:41 PM	17	1272.00	CEUX
GENMAB A/S	14-Apr-2025	3:28:41 PM	21	1272.00	CEUX
GENMAB A/S	14-Apr-2025	3:28:41 PM	6	1272.00	CEUX

Exhibit 99.1(a)

APPENDIX Share buy-back programme - Specification for April 14 – April 18, 2025

GENMAB A/S	14-Apr-2025	3:28:41 PM	6	1272.00	CEUX
GENMAB A/S	14-Apr-2025	3:28:41 PM	6	1272.00	CEUX
GENMAB A/S	14-Apr-2025	3:28:42 PM	6	1272.00	CEUX
GENMAB A/S	14-Apr-2025	3:29:02 PM	41	1272.00	XCSE
GENMAB A/S	14-Apr-2025	3:29:02 PM	12	1272.00	CEUX
GENMAB A/S	14-Apr-2025	3:29:10 PM	7	1272.50	XCSE
GENMAB A/S	14-Apr-2025	3:29:10 PM	48	1272.50	XCSE
GENMAB A/S	14-Apr-2025	3:29:10 PM	10	1272.50	XCSE
GENMAB A/S	14-Apr-2025	3:29:10 PM	13	1272.50	XCSE
GENMAB A/S	14-Apr-2025	3:29:10 PM	10	1272.50	XCSE
GENMAB A/S	14-Apr-2025	3:29:11 PM	12	1272.50	XCSE
GENMAB A/S	14-Apr-2025	3:29:11 PM	13	1272.50	XCSE
GENMAB A/S	14-Apr-2025	3:29:11 PM	13	1272.50	XCSE
GENMAB A/S	14-Apr-2025	3:29:15 PM	6	1271.50	XCSE
GENMAB A/S	14-Apr-2025	3:29:15 PM	63	1271.50	XCSE
GENMAB A/S	14-Apr-2025	3:29:15 PM	19	1271.50	XCSE
GENMAB A/S	14-Apr-2025	3:30:00 PM	35	1272.00	XCSE
GENMAB A/S	14-Apr-2025	3:30:00 PM	12	1272.00	XCSE
GENMAB A/S	14-Apr-2025	3:30:00 PM	40	1272.00	XCSE
GENMAB A/S	14-Apr-2025	3:30:00 PM	36	1272.00	CEUX
GENMAB A/S	14-Apr-2025	3:30:01 PM	4	1271.00	TQEX
GENMAB A/S	14-Apr-2025	3:30:01 PM	7	1271.00	TQEX
GENMAB A/S	14-Apr-2025	3:30:01 PM	2	1271.00	TQEX
GENMAB A/S	14-Apr-2025	3:30:01 PM	12	1271.00	TQEX
GENMAB A/S	14-Apr-2025	3:30:01 PM	36	1272.00	CEUX
GENMAB A/S	14-Apr-2025	3:30:01 PM	1	1272.00	CEUX
GENMAB A/S	14-Apr-2025	3:30:01 PM	49	1272.00	CEUX
GENMAB A/S	14-Apr-2025	3:30:10 PM	86	1272.00	XCSE
GENMAB A/S	14-Apr-2025	3:30:10 PM	22	1272.00	XCSE
GENMAB A/S	14-Apr-2025	3:30:10 PM	3	1272.00	XCSE
GENMAB A/S	14-Apr-2025	3:30:10 PM	5	1272.00	XCSE
GENMAB A/S	14-Apr-2025	3:30:10 PM	15	1272.00	XCSE
GENMAB A/S	14-Apr-2025	3:30:10 PM	50	1272.00	TQEX
GENMAB A/S	14-Apr-2025	3:30:10 PM	2	1272.00	TQEX
GENMAB A/S	14-Apr-2025	3:30:10 PM	45	1272.00	AQEU
GENMAB A/S	14-Apr-2025	3:30:22 PM	5	1272.00	CEUX
GENMAB A/S	14-Apr-2025	3:30:22 PM	6	1272.00	CEUX
GENMAB A/S	14-Apr-2025	3:30:22 PM	5	1272.00	CEUX
GENMAB A/S	14-Apr-2025	3:30:23 PM	3	1271.50	XCSE
GENMAB A/S	14-Apr-2025	3:30:23 PM	5	1271.00	TQEX
GENMAB A/S	14-Apr-2025	3:30:23 PM	2	1271.00	TQEX
GENMAB A/S	14-Apr-2025	3:30:23 PM	5	1271.00	TQEX
GENMAB A/S	14-Apr-2025	3:30:23 PM	2	1271.00	TQEX

Exhibit 99.1(a)

APPENDIX Share buy-back programme - Specification for April 14 – April 18, 2025

GENMAB A/S	14-Apr-2025	3:30:23 PM	5	1271.00	TQEX
GENMAB A/S	14-Apr-2025	3:30:23 PM	2	1271.00	TQEX
GENMAB A/S	14-Apr-2025	3:30:23 PM	3	1271.00	TQEX
GENMAB A/S	14-Apr-2025	3:30:23 PM	1	1271.00	TQEX
GENMAB A/S	14-Apr-2025	3:30:23 PM	1	1271.50	CEUX
GENMAB A/S	14-Apr-2025	3:30:23 PM	2	1271.50	CEUX
GENMAB A/S	14-Apr-2025	3:30:23 PM	10	1271.50	CEUX
GENMAB A/S	14-Apr-2025	3:30:23 PM	3	1271.50	CEUX
GENMAB A/S	14-Apr-2025	3:30:23 PM	2	1271.50	CEUX
GENMAB A/S	14-Apr-2025	3:30:23 PM	4	1271.50	CEUX
GENMAB A/S	14-Apr-2025	3:30:23 PM	4	1271.50	CEUX
GENMAB A/S	14-Apr-2025	3:30:23 PM	4	1271.00	CEUX
GENMAB A/S	14-Apr-2025	3:30:23 PM	3	1271.00	CEUX
GENMAB A/S	14-Apr-2025	3:30:23 PM	4	1271.00	CEUX
GENMAB A/S	14-Apr-2025	3:30:26 PM	8	1271.00	XCSE
GENMAB A/S	14-Apr-2025	3:30:26 PM	7	1271.00	XCSE
GENMAB A/S	14-Apr-2025	3:30:26 PM	3	1271.00	XCSE
GENMAB A/S	14-Apr-2025	3:30:26 PM	7	1271.00	XCSE
GENMAB A/S	14-Apr-2025	3:30:26 PM	13	1271.50	XCSE
GENMAB A/S	14-Apr-2025	3:30:26 PM	12	1271.50	XCSE
GENMAB A/S	14-Apr-2025	3:30:26 PM	22	1271.50	XCSE
GENMAB A/S	14-Apr-2025	3:30:26 PM	8	1271.50	XCSE
GENMAB A/S	14-Apr-2025	3:30:26 PM	12	1271.50	XCSE
GENMAB A/S	14-Apr-2025	3:30:26 PM	11	1271.50	XCSE
GENMAB A/S	14-Apr-2025	3:30:26 PM	12	1271.50	XCSE
GENMAB A/S	14-Apr-2025	3:30:26 PM	1	1271.50	XCSE
GENMAB A/S	14-Apr-2025	3:30:26 PM	21	1271.50	XCSE
GENMAB A/S	14-Apr-2025	3:30:26 PM	64	1271.00	XCSE
GENMAB A/S	14-Apr-2025	3:30:26 PM	3	1271.00	XCSE
GENMAB A/S	14-Apr-2025	3:30:26 PM	21	1271.00	XCSE
GENMAB A/S	14-Apr-2025	3:30:26 PM	3	1271.00	AQEU
GENMAB A/S	14-Apr-2025	3:30:26 PM	3	1271.00	AQEU
GENMAB A/S	14-Apr-2025	3:30:26 PM	20	1271.00	AQEU
GENMAB A/S	14-Apr-2025	3:30:26 PM	6	1271.00	AQEU
GENMAB A/S	14-Apr-2025	3:30:26 PM	24	1271.00	CEUX
GENMAB A/S	14-Apr-2025	3:30:26 PM	20	1271.00	CEUX
GENMAB A/S	14-Apr-2025	3:30:26 PM	33	1271.00	CEUX
GENMAB A/S	14-Apr-2025	3:30:26 PM	6	1271.00	CEUX
GENMAB A/S	14-Apr-2025	3:30:26 PM	6	1271.00	CEUX
GENMAB A/S	14-Apr-2025	3:30:26 PM	42	1271.00	CEUX
GENMAB A/S	14-Apr-2025	3:30:28 PM	13	1271.00	XCSE
GENMAB A/S	14-Apr-2025	3:30:29 PM	10	1271.00	XCSE
GENMAB A/S	14-Apr-2025	3:30:29 PM	13	1271.00	XCSE

Exhibit 99.1(a)

APPENDIX Share buy-back programme - Specification for April 14 – April 18, 2025

GENMAB A/S	14-Apr-2025	3:30:30 PM	11	1271.00	XCSE
GENMAB A/S	14-Apr-2025	3:30:36 PM	7	1270.50	CEUX
GENMAB A/S	14-Apr-2025	3:30:36 PM	7	1270.50	CEUX
GENMAB A/S	14-Apr-2025	3:30:36 PM	4	1270.50	CEUX
GENMAB A/S	14-Apr-2025	3:30:36 PM	3	1270.00	CEUX
GENMAB A/S	14-Apr-2025	3:30:36 PM	2	1270.00	CEUX
GENMAB A/S	14-Apr-2025	3:30:36 PM	2	1270.00	CEUX
GENMAB A/S	14-Apr-2025	3:30:36 PM	2	1270.00	CEUX
GENMAB A/S	14-Apr-2025	3:30:36 PM	2	1270.00	CEUX
GENMAB A/S	14-Apr-2025	3:30:36 PM	2	1270.00	CEUX
GENMAB A/S	14-Apr-2025	3:30:36 PM	2	1270.00	CEUX
GENMAB A/S	14-Apr-2025	3:30:36 PM	12	1270.00	CEUX
GENMAB A/S	14-Apr-2025	3:30:36 PM	12	1270.00	CEUX
GENMAB A/S	14-Apr-2025	3:30:36 PM	6	1270.00	CEUX
GENMAB A/S	14-Apr-2025	3:30:36 PM	2	1270.00	CEUX
GENMAB A/S	14-Apr-2025	3:30:38 PM	3	1270.00	CEUX
GENMAB A/S	14-Apr-2025	3:30:38 PM	3	1270.00	CEUX
GENMAB A/S	14-Apr-2025	3:30:38 PM	2	1270.00	CEUX
GENMAB A/S	14-Apr-2025	3:30:38 PM	3	1270.00	CEUX
GENMAB A/S	14-Apr-2025	3:30:39 PM	86	1270.00	XCSE
GENMAB A/S	14-Apr-2025	3:30:39 PM	26	1270.00	CEUX
GENMAB A/S	14-Apr-2025	3:30:41 PM	40	1270.00	XCSE
GENMAB A/S	14-Apr-2025	3:30:41 PM	5	1269.50	TQEX
GENMAB A/S	14-Apr-2025	3:30:41 PM	2	1269.50	TQEX
GENMAB A/S	14-Apr-2025	3:30:41 PM	3	1269.50	TQEX
GENMAB A/S	14-Apr-2025	3:30:41 PM	2	1269.50	TQEX
GENMAB A/S	14-Apr-2025	3:30:41 PM	10	1269.50	TQEX
GENMAB A/S	14-Apr-2025	3:30:41 PM	2	1269.50	TQEX
GENMAB A/S	14-Apr-2025	3:30:41 PM	5	1269.50	AQEU
GENMAB A/S	14-Apr-2025	3:30:41 PM	4	1269.50	AQEU
GENMAB A/S	14-Apr-2025	3:30:41 PM	3	1269.50	AQEU
GENMAB A/S	14-Apr-2025	3:30:41 PM	1	1270.00	CEUX
GENMAB A/S	14-Apr-2025	3:31:16 PM	88	1270.00	XCSE
GENMAB A/S	14-Apr-2025	3:31:16 PM	22	1270.00	XCSE
GENMAB A/S	14-Apr-2025	3:31:16 PM	19	1270.00	XCSE
GENMAB A/S	14-Apr-2025	3:31:16 PM	40	1270.00	XCSE
GENMAB A/S	14-Apr-2025	3:31:16 PM	11	1270.00	XCSE
GENMAB A/S	14-Apr-2025	3:31:16 PM	2	1270.00	XCSE
GENMAB A/S	14-Apr-2025	3:31:16 PM	9	1270.00	XCSE
GENMAB A/S	14-Apr-2025	3:31:16 PM	9	1270.00	XCSE
GENMAB A/S	14-Apr-2025	3:31:16 PM	88	1269.50	XCSE
GENMAB A/S	14-Apr-2025	3:31:16 PM	32	1270.50	TQEX
GENMAB A/S	14-Apr-2025	3:31:16 PM	1	1269.50	TQEX

Exhibit 99.1(a)

APPENDIX Share buy-back programme - Specification for April 14 – April 18, 2025

GENMAB A/S	14-Apr-2025	3:31:16 PM	34	1270.00	AQEU
GENMAB A/S	14-Apr-2025	3:31:16 PM	37	1269.00	AQEU
GENMAB A/S	14-Apr-2025	3:31:16 PM	2	1270.50	CEUX
GENMAB A/S	14-Apr-2025	3:31:16 PM	4	1270.50	CEUX
GENMAB A/S	14-Apr-2025	3:31:16 PM	21	1270.50	CEUX
GENMAB A/S	14-Apr-2025	3:31:16 PM	5	1270.50	CEUX
GENMAB A/S	14-Apr-2025	3:31:16 PM	71	1270.00	CEUX
GENMAB A/S	14-Apr-2025	3:31:16 PM	11	1270.00	CEUX
GENMAB A/S	14-Apr-2025	3:31:16 PM	83	1269.50	CEUX
GENMAB A/S	14-Apr-2025	3:31:24 PM	18	1269.00	XCSE
GENMAB A/S	14-Apr-2025	3:31:24 PM	13	1269.00	XCSE
GENMAB A/S	14-Apr-2025	3:31:24 PM	12	1269.00	XCSE
GENMAB A/S	14-Apr-2025	3:31:24 PM	3	1269.00	XCSE
GENMAB A/S	14-Apr-2025	3:31:24 PM	7	1269.00	XCSE
GENMAB A/S	14-Apr-2025	3:31:24 PM	8	1269.00	XCSE
GENMAB A/S	14-Apr-2025	3:31:24 PM	10	1269.00	XCSE
GENMAB A/S	14-Apr-2025	3:31:24 PM	10	1269.00	XCSE
GENMAB A/S	14-Apr-2025	3:31:24 PM	75	1268.50	XCSE
GENMAB A/S	14-Apr-2025	3:31:24 PM	19	1268.50	TQEX
GENMAB A/S	14-Apr-2025	3:31:24 PM	6	1268.50	TQEX
GENMAB A/S	14-Apr-2025	3:31:24 PM	4	1268.50	TQEX
GENMAB A/S	14-Apr-2025	3:31:24 PM	2	1268.50	TQEX
GENMAB A/S	14-Apr-2025	3:31:24 PM	2	1268.50	TQEX
GENMAB A/S	14-Apr-2025	3:31:24 PM	2	1268.50	TQEX
GENMAB A/S	14-Apr-2025	3:31:24 PM	6	1268.50	TQEX
GENMAB A/S	14-Apr-2025	3:31:24 PM	4	1268.50	CEUX
GENMAB A/S	14-Apr-2025	3:31:24 PM	20	1268.50	CEUX
GENMAB A/S	14-Apr-2025	3:31:24 PM	7	1268.50	CEUX
GENMAB A/S	14-Apr-2025	3:31:38 PM	9	1268.50	XCSE
GENMAB A/S	14-Apr-2025	3:31:38 PM	4	1268.00	TQEX
GENMAB A/S	14-Apr-2025	3:31:38 PM	2	1268.00	TQEX
GENMAB A/S	14-Apr-2025	3:31:38 PM	5	1268.00	TQEX
GENMAB A/S	14-Apr-2025	3:31:38 PM	8	1268.00	TQEX
GENMAB A/S	14-Apr-2025	3:31:38 PM	4	1268.50	CEUX
GENMAB A/S	14-Apr-2025	3:31:38 PM	35	1268.50	CEUX
GENMAB A/S	14-Apr-2025	3:31:38 PM	17	1268.50	CEUX
GENMAB A/S	14-Apr-2025	3:31:49 PM	85	1267.50	XCSE
GENMAB A/S	14-Apr-2025	3:31:49 PM	82	1267.50	CEUX
GENMAB A/S	14-Apr-2025	3:32:17 PM	55	1269.00	CEUX
GENMAB A/S	14-Apr-2025	3:32:21 PM	86	1269.00	XCSE
GENMAB A/S	14-Apr-2025	3:32:21 PM	12	1269.00	XCSE
GENMAB A/S	14-Apr-2025	3:32:21 PM	9	1269.00	XCSE
GENMAB A/S	14-Apr-2025	3:32:21 PM	25	1269.00	TQEX

Exhibit 99.1(a)

APPENDIX Share buy-back programme - Specification for April 14 – April 18, 2025

GENMAB A/S	14-Apr-2025	3:32:21 PM	30	1269.00	CEUX
GENMAB A/S	14-Apr-2025	3:32:25 PM	82	1268.00	XCSE
GENMAB A/S	14-Apr-2025	3:32:25 PM	35	1267.50	XCSE
GENMAB A/S	14-Apr-2025	3:32:25 PM	15	1267.50	XCSE
GENMAB A/S	14-Apr-2025	3:32:25 PM	40	1268.00	XCSE
GENMAB A/S	14-Apr-2025	3:32:25 PM	11	1268.00	XCSE
GENMAB A/S	14-Apr-2025	3:32:25 PM	5	1268.00	XCSE
GENMAB A/S	14-Apr-2025	3:32:25 PM	6	1268.00	XCSE
GENMAB A/S	14-Apr-2025	3:32:25 PM	14	1267.00	XCSE
GENMAB A/S	14-Apr-2025	3:32:25 PM	75	1267.00	XCSE
GENMAB A/S	14-Apr-2025	3:32:25 PM	33	1268.00	TQEX
GENMAB A/S	14-Apr-2025	3:32:25 PM	25	1268.50	AQEU
GENMAB A/S	14-Apr-2025	3:32:25 PM	6	1268.00	CEUX
GENMAB A/S	14-Apr-2025	3:32:25 PM	14	1268.00	CEUX
GENMAB A/S	14-Apr-2025	3:32:25 PM	68	1268.00	CEUX
GENMAB A/S	14-Apr-2025	3:32:25 PM	35	1267.00	CEUX
GENMAB A/S	14-Apr-2025	3:32:25 PM	51	1267.00	CEUX
GENMAB A/S	14-Apr-2025	3:32:33 PM	20	1266.50	XCSE
GENMAB A/S	14-Apr-2025	3:32:33 PM	68	1266.50	XCSE
GENMAB A/S	14-Apr-2025	3:32:33 PM	3	1266.50	XCSE
GENMAB A/S	14-Apr-2025	3:32:33 PM	7	1266.50	XCSE
GENMAB A/S	14-Apr-2025	3:32:33 PM	4	1266.50	XCSE
GENMAB A/S	14-Apr-2025	3:32:33 PM	2	1266.50	XCSE
GENMAB A/S	14-Apr-2025	3:32:33 PM	3	1266.50	XCSE
GENMAB A/S	14-Apr-2025	3:32:33 PM	19	1266.50	XCSE
GENMAB A/S	14-Apr-2025	3:32:33 PM	2	1266.50	XCSE
GENMAB A/S	14-Apr-2025	3:32:33 PM	5	1266.50	XCSE
GENMAB A/S	14-Apr-2025	3:32:33 PM	3	1266.50	XCSE
GENMAB A/S	14-Apr-2025	3:32:33 PM	6	1266.50	XCSE
GENMAB A/S	14-Apr-2025	3:32:33 PM	6	1267.00	XCSE
GENMAB A/S	14-Apr-2025	3:32:33 PM	40	1267.00	XCSE
GENMAB A/S	14-Apr-2025	3:32:33 PM	12	1267.00	XCSE
GENMAB A/S	14-Apr-2025	3:32:38 PM	7	1265.50	CEUX
GENMAB A/S	14-Apr-2025	3:32:38 PM	7	1265.50	CEUX
GENMAB A/S	14-Apr-2025	3:32:38 PM	11	1265.50	CEUX
GENMAB A/S	14-Apr-2025	3:32:38 PM	13	1265.50	CEUX
GENMAB A/S	14-Apr-2025	3:32:41 PM	9	1265.50	XCSE
GENMAB A/S	14-Apr-2025	3:32:41 PM	5	1265.50	XCSE
GENMAB A/S	14-Apr-2025	3:32:41 PM	3	1265.50	XCSE
GENMAB A/S	14-Apr-2025	3:32:41 PM	10	1265.50	XCSE
GENMAB A/S	14-Apr-2025	3:32:41 PM	2	1265.50	XCSE
GENMAB A/S	14-Apr-2025	3:32:41 PM	11	1265.50	XCSE
GENMAB A/S	14-Apr-2025	3:32:41 PM	47	1265.50	XCSE

Exhibit 99.1(a)

APPENDIX Share buy-back programme - Specification for April 14 – April 18, 2025

GENMAB A/S	14-Apr-2025	3:32:41 PM	6	1265.50	AQEU
GENMAB A/S	14-Apr-2025	3:32:41 PM	25	1265.50	AQEU
GENMAB A/S	14-Apr-2025	3:32:41 PM	3	1265.50	CEUX
GENMAB A/S	14-Apr-2025	3:32:41 PM	5	1265.50	CEUX
GENMAB A/S	14-Apr-2025	3:32:41 PM	12	1265.50	CEUX
GENMAB A/S	14-Apr-2025	3:32:41 PM	15	1265.50	CEUX
GENMAB A/S	14-Apr-2025	3:32:41 PM	15	1265.50	CEUX
GENMAB A/S	14-Apr-2025	3:32:49 PM	64	1264.50	XCSE
GENMAB A/S	14-Apr-2025	3:33:02 PM	25	1264.50	XCSE
GENMAB A/S	14-Apr-2025	3:33:11 PM	79	1265.00	XCSE
GENMAB A/S	14-Apr-2025	3:33:11 PM	9	1265.00	XCSE
GENMAB A/S	14-Apr-2025	3:33:11 PM	6	1265.00	TQEX
GENMAB A/S	14-Apr-2025	3:33:11 PM	4	1265.00	TQEX
GENMAB A/S	14-Apr-2025	3:33:39 PM	2	1265.00	XCSE
GENMAB A/S	14-Apr-2025	3:33:55 PM	83	1265.00	XCSE
GENMAB A/S	14-Apr-2025	3:33:55 PM	112	1265.00	XCSE
GENMAB A/S	14-Apr-2025	3:33:55 PM	50	1265.00	XCSE
GENMAB A/S	14-Apr-2025	3:33:55 PM	21	1265.00	XCSE
GENMAB A/S	14-Apr-2025	3:33:55 PM	40	1265.00	XCSE
GENMAB A/S	14-Apr-2025	3:33:55 PM	1	1265.00	AQEU
GENMAB A/S	14-Apr-2025	3:33:55 PM	28	1265.00	AQEU
GENMAB A/S	14-Apr-2025	3:33:55 PM	4	1265.50	CEUX
GENMAB A/S	14-Apr-2025	3:33:55 PM	8	1265.50	CEUX
GENMAB A/S	14-Apr-2025	3:33:55 PM	7	1265.50	CEUX
GENMAB A/S	14-Apr-2025	3:33:55 PM	5	1265.50	CEUX
GENMAB A/S	14-Apr-2025	3:33:55 PM	1	1265.50	CEUX
GENMAB A/S	14-Apr-2025	3:33:55 PM	10	1264.50	CEUX
GENMAB A/S	14-Apr-2025	3:33:55 PM	30	1264.50	CEUX
GENMAB A/S	14-Apr-2025	3:33:55 PM	48	1264.50	CEUX
GENMAB A/S	14-Apr-2025	3:34:06 PM	2	1264.00	XCSE
GENMAB A/S	14-Apr-2025	3:34:06 PM	2	1264.00	XCSE
GENMAB A/S	14-Apr-2025	3:34:06 PM	5	1264.00	XCSE
GENMAB A/S	14-Apr-2025	3:34:06 PM	79	1264.00	XCSE
GENMAB A/S	14-Apr-2025	3:34:06 PM	11	1264.00	XCSE
GENMAB A/S	14-Apr-2025	3:34:06 PM	5	1264.00	XCSE
GENMAB A/S	14-Apr-2025	3:34:06 PM	3	1264.00	XCSE
GENMAB A/S	14-Apr-2025	3:34:06 PM	2	1264.00	XCSE
GENMAB A/S	14-Apr-2025	3:34:06 PM	5	1264.00	XCSE
GENMAB A/S	14-Apr-2025	3:34:06 PM	2	1264.00	XCSE
GENMAB A/S	14-Apr-2025	3:34:06 PM	13	1264.00	XCSE
GENMAB A/S	14-Apr-2025	3:34:06 PM	40	1264.50	XCSE
GENMAB A/S	14-Apr-2025	3:34:06 PM	23	1264.50	XCSE
GENMAB A/S	14-Apr-2025	3:34:06 PM	8	1264.50	XCSE

Exhibit 99.1(a)

APPENDIX Share buy-back programme - Specification for April 14 – April 18, 2025

GENMAB A/S	14-Apr-2025	3:34:06 PM	15	1264.00	TQEX
GENMAB A/S	14-Apr-2025	3:34:06 PM	3	1264.00	TQEX
GENMAB A/S	14-Apr-2025	3:34:06 PM	2	1264.00	TQEX
GENMAB A/S	14-Apr-2025	3:34:06 PM	4	1264.00	TQEX
GENMAB A/S	14-Apr-2025	3:34:06 PM	4	1264.00	TQEX
GENMAB A/S	14-Apr-2025	3:34:06 PM	3	1263.50	AQEU
GENMAB A/S	14-Apr-2025	3:34:06 PM	20	1263.50	AQEU
GENMAB A/S	14-Apr-2025	3:34:06 PM	5	1263.50	CEUX
GENMAB A/S	14-Apr-2025	3:34:06 PM	8	1263.50	CEUX
GENMAB A/S	14-Apr-2025	3:34:06 PM	12	1263.50	CEUX
GENMAB A/S	14-Apr-2025	3:34:06 PM	28	1263.50	CEUX
GENMAB A/S	14-Apr-2025	3:34:06 PM	15	1263.50	CEUX
GENMAB A/S	14-Apr-2025	3:34:06 PM	10	1263.50	CEUX
GENMAB A/S	14-Apr-2025	3:34:06 PM	4	1263.50	CEUX
GENMAB A/S	14-Apr-2025	3:34:12 PM	30	1264.00	XCSE
GENMAB A/S	14-Apr-2025	3:34:15 PM	23	1264.00	XCSE
GENMAB A/S	14-Apr-2025	3:34:15 PM	31	1264.00	XCSE
GENMAB A/S	14-Apr-2025	3:34:15 PM	5	1264.00	XCSE
GENMAB A/S	14-Apr-2025	3:34:15 PM	83	1264.00	XCSE
GENMAB A/S	14-Apr-2025	3:34:15 PM	25	1263.50	TQEX
GENMAB A/S	14-Apr-2025	3:34:15 PM	5	1263.00	CEUX
GENMAB A/S	14-Apr-2025	3:34:15 PM	5	1263.00	CEUX
GENMAB A/S	14-Apr-2025	3:34:15 PM	15	1263.00	CEUX
GENMAB A/S	14-Apr-2025	3:34:15 PM	4	1263.00	CEUX
GENMAB A/S	14-Apr-2025	3:34:15 PM	3	1263.00	CEUX
GENMAB A/S	14-Apr-2025	3:34:15 PM	4	1263.00	CEUX
GENMAB A/S	14-Apr-2025	3:34:15 PM	3	1263.00	CEUX
GENMAB A/S	14-Apr-2025	3:34:15 PM	2	1263.00	CEUX
GENMAB A/S	14-Apr-2025	3:34:15 PM	3	1263.00	CEUX
GENMAB A/S	14-Apr-2025	3:34:15 PM	2	1263.00	CEUX
GENMAB A/S	14-Apr-2025	3:34:15 PM	4	1263.00	CEUX
GENMAB A/S	14-Apr-2025	3:34:15 PM	10	1263.00	CEUX
GENMAB A/S	14-Apr-2025	3:34:16 PM	7	1263.50	TQEX
GENMAB A/S	14-Apr-2025	3:34:16 PM	15	1263.50	TQEX
GENMAB A/S	14-Apr-2025	3:34:16 PM	4	1263.50	TQEX
GENMAB A/S	14-Apr-2025	3:34:17 PM	85	1263.00	XCSE
GENMAB A/S	14-Apr-2025	3:34:17 PM	10	1263.00	XCSE
GENMAB A/S	14-Apr-2025	3:34:17 PM	10	1263.00	XCSE
GENMAB A/S	14-Apr-2025	3:34:17 PM	10	1263.00	XCSE
GENMAB A/S	14-Apr-2025	3:34:17 PM	10	1263.00	XCSE
GENMAB A/S	14-Apr-2025	3:34:17 PM	13	1263.00	XCSE
GENMAB A/S	14-Apr-2025	3:34:17 PM	25	1263.00	CEUX
GENMAB A/S	14-Apr-2025	3:34:18 PM	4	1262.00	XCSE

Exhibit 99.1(a)

APPENDIX Share buy-back programme - Specification for April 14 – April 18, 2025

GENMAB A/S	14-Apr-2025	3:34:18 PM	28	1262.00	XCSE
GENMAB A/S	14-Apr-2025	3:34:18 PM	3	1262.00	CEUX
GENMAB A/S	14-Apr-2025	3:34:18 PM	4	1262.00	CEUX
GENMAB A/S	14-Apr-2025	3:34:18 PM	2	1262.00	CEUX
GENMAB A/S	14-Apr-2025	3:34:18 PM	5	1262.00	CEUX
GENMAB A/S	14-Apr-2025	3:34:18 PM	25	1262.00	CEUX
GENMAB A/S	14-Apr-2025	3:34:18 PM	16	1262.00	CEUX
GENMAB A/S	14-Apr-2025	3:34:19 PM	35	1262.50	CEUX
GENMAB A/S	14-Apr-2025	3:35:02 PM	4	1263.50	TQEX
GENMAB A/S	14-Apr-2025	3:35:02 PM	3	1263.50	TQEX
GENMAB A/S	14-Apr-2025	3:35:02 PM	2	1263.50	TQEX
GENMAB A/S	14-Apr-2025	3:35:02 PM	3	1263.50	TQEX
GENMAB A/S	14-Apr-2025	3:35:02 PM	9	1263.50	TQEX
GENMAB A/S	14-Apr-2025	3:35:02 PM	3	1263.50	CEUX
GENMAB A/S	14-Apr-2025	3:35:02 PM	5	1263.50	CEUX
GENMAB A/S	14-Apr-2025	3:35:02 PM	11	1263.50	CEUX
GENMAB A/S	14-Apr-2025	3:35:02 PM	3	1263.50	CEUX
GENMAB A/S	14-Apr-2025	3:35:02 PM	13	1263.50	CEUX
GENMAB A/S	14-Apr-2025	3:35:02 PM	7	1263.50	CEUX
GENMAB A/S	14-Apr-2025	3:35:18 PM	2	1265.50	XCSE
GENMAB A/S	14-Apr-2025	3:35:18 PM	2	1265.50	XCSE
GENMAB A/S	14-Apr-2025	3:35:18 PM	2	1265.50	XCSE
GENMAB A/S	14-Apr-2025	3:35:18 PM	7	1266.00	AQEU
GENMAB A/S	14-Apr-2025	3:35:18 PM	19	1266.00	AQEU
GENMAB A/S	14-Apr-2025	3:35:19 PM	7	1265.50	XCSE
GENMAB A/S	14-Apr-2025	3:35:19 PM	3	1265.50	XCSE
GENMAB A/S	14-Apr-2025	3:35:19 PM	2	1265.50	XCSE
GENMAB A/S	14-Apr-2025	3:35:19 PM	13	1265.50	XCSE
GENMAB A/S	14-Apr-2025	3:35:19 PM	4	1265.00	CEUX
GENMAB A/S	14-Apr-2025	3:35:19 PM	3	1265.00	CEUX
GENMAB A/S	14-Apr-2025	3:35:19 PM	3	1265.00	CEUX
GENMAB A/S	14-Apr-2025	3:35:19 PM	2	1265.00	CEUX
GENMAB A/S	14-Apr-2025	3:35:21 PM	28	1265.00	XCSE
GENMAB A/S	14-Apr-2025	3:35:21 PM	5	1265.00	AQEU
GENMAB A/S	14-Apr-2025	3:35:21 PM	5	1265.00	AQEU
GENMAB A/S	14-Apr-2025	3:35:21 PM	15	1265.00	AQEU
GENMAB A/S	14-Apr-2025	3:35:21 PM	3	1265.00	CEUX
GENMAB A/S	14-Apr-2025	3:35:21 PM	22	1265.00	CEUX
GENMAB A/S	14-Apr-2025	3:35:21 PM	52	1265.00	CEUX
GENMAB A/S	14-Apr-2025	3:35:25 PM	59	1265.00	XCSE
GENMAB A/S	14-Apr-2025	3:35:25 PM	15	1264.00	XCSE
GENMAB A/S	14-Apr-2025	3:35:25 PM	7	1264.00	XCSE
GENMAB A/S	14-Apr-2025	3:35:25 PM	5	1264.00	XCSE

Exhibit 99.1(a)

APPENDIX Share buy-back programme - Specification for April 14 – April 18, 2025

GENMAB A/S	14-Apr-2025	3:35:25 PM	3	1264.00	XCSE
GENMAB A/S	14-Apr-2025	3:35:25 PM	6	1264.00	XCSE
GENMAB A/S	14-Apr-2025	3:35:25 PM	48	1264.00	XCSE
GENMAB A/S	14-Apr-2025	3:35:50 PM	76	1263.00	XCSE
GENMAB A/S	14-Apr-2025	3:35:50 PM	14	1262.50	TQEX
GENMAB A/S	14-Apr-2025	3:35:50 PM	2	1262.50	TQEX
GENMAB A/S	14-Apr-2025	3:35:50 PM	43	1263.50	CEUX
GENMAB A/S	14-Apr-2025	3:35:51 PM	10	1262.50	CEUX
GENMAB A/S	14-Apr-2025	3:35:51 PM	2	1262.50	CEUX
GENMAB A/S	14-Apr-2025	3:35:51 PM	2	1262.50	CEUX
GENMAB A/S	14-Apr-2025	3:35:51 PM	28	1262.50	CEUX
GENMAB A/S	14-Apr-2025	3:35:51 PM	3	1262.50	CEUX
GENMAB A/S	14-Apr-2025	3:35:51 PM	2	1262.50	CEUX
GENMAB A/S	14-Apr-2025	3:35:58 PM	1	1262.00	XCSE
GENMAB A/S	14-Apr-2025	3:35:58 PM	1	1262.00	XCSE
GENMAB A/S	14-Apr-2025	3:36:07 PM	8	1263.50	CEUX
GENMAB A/S	14-Apr-2025	3:36:07 PM	12	1263.50	CEUX
GENMAB A/S	14-Apr-2025	3:36:07 PM	2	1263.50	CEUX
GENMAB A/S	14-Apr-2025	3:36:07 PM	13	1263.50	CEUX
GENMAB A/S	14-Apr-2025	3:36:07 PM	4	1263.50	CEUX
GENMAB A/S	14-Apr-2025	3:36:07 PM	5	1263.50	CEUX
GENMAB A/S	14-Apr-2025	3:36:13 PM	21	1263.50	CEUX
GENMAB A/S	14-Apr-2025	3:36:16 PM	17	1263.50	CEUX
GENMAB A/S	14-Apr-2025	3:36:17 PM	6	1263.50	CEUX
GENMAB A/S	14-Apr-2025	3:36:49 PM	5	1264.50	TQEX
GENMAB A/S	14-Apr-2025	3:36:50 PM	11	1264.50	XCSE
GENMAB A/S	14-Apr-2025	3:36:50 PM	12	1264.50	XCSE
GENMAB A/S	14-Apr-2025	3:36:50 PM	13	1264.50	XCSE
GENMAB A/S	14-Apr-2025	3:36:50 PM	13	1264.50	XCSE
GENMAB A/S	14-Apr-2025	3:36:50 PM	27	1264.50	XCSE
GENMAB A/S	14-Apr-2025	3:36:50 PM	25	1264.50	XCSE
GENMAB A/S	14-Apr-2025	3:36:50 PM	10	1264.50	TQEX
GENMAB A/S	14-Apr-2025	3:36:50 PM	19	1264.50	TQEX
GENMAB A/S	14-Apr-2025	3:37:04 PM	40	1265.00	XCSE
GENMAB A/S	14-Apr-2025	3:37:04 PM	18	1265.00	XCSE
GENMAB A/S	14-Apr-2025	3:37:04 PM	25	1265.00	XCSE
GENMAB A/S	14-Apr-2025	3:37:04 PM	3	1265.00	XCSE
GENMAB A/S	14-Apr-2025	3:37:04 PM	22	1265.00	XCSE
GENMAB A/S	14-Apr-2025	3:37:04 PM	4	1265.00	XCSE
GENMAB A/S	14-Apr-2025	3:37:04 PM	1	1264.50	XCSE
GENMAB A/S	14-Apr-2025	3:37:04 PM	3	1264.50	XCSE
GENMAB A/S	14-Apr-2025	3:37:04 PM	2	1264.50	XCSE
GENMAB A/S	14-Apr-2025	3:37:04 PM	3	1264.50	XCSE

Exhibit 99.1(a)

APPENDIX Share buy-back programme - Specification for April 14 – April 18, 2025

GENMAB A/S	14-Apr-2025	3:37:04 PM	3	1264.50	XCSE
GENMAB A/S	14-Apr-2025	3:37:04 PM	2	1264.50	XCSE
GENMAB A/S	14-Apr-2025	3:37:04 PM	25	1265.00	AQEU
GENMAB A/S	14-Apr-2025	3:37:04 PM	17	1264.50	CEUX
GENMAB A/S	14-Apr-2025	3:37:04 PM	2	1264.50	CEUX
GENMAB A/S	14-Apr-2025	3:37:04 PM	14	1264.50	CEUX
GENMAB A/S	14-Apr-2025	3:37:04 PM	4	1264.50	CEUX
GENMAB A/S	14-Apr-2025	3:37:04 PM	2	1264.50	CEUX
GENMAB A/S	14-Apr-2025	3:37:05 PM	6	1264.50	CEUX
GENMAB A/S	14-Apr-2025	3:37:06 PM	71	1264.50	XCSE
GENMAB A/S	14-Apr-2025	3:37:06 PM	40	1264.50	CEUX
GENMAB A/S	14-Apr-2025	3:37:06 PM	3	1263.50	CEUX
GENMAB A/S	14-Apr-2025	3:37:06 PM	3	1263.50	CEUX
GENMAB A/S	14-Apr-2025	3:37:06 PM	18	1263.50	CEUX
GENMAB A/S	14-Apr-2025	3:37:40 PM	5	1265.00	TQEX
GENMAB A/S	14-Apr-2025	3:37:40 PM	5	1265.00	TQEX
GENMAB A/S	14-Apr-2025	3:37:40 PM	5	1265.00	TQEX
GENMAB A/S	14-Apr-2025	3:37:40 PM	5	1265.00	TQEX
GENMAB A/S	14-Apr-2025	3:37:43 PM	2	1265.00	AQEU
GENMAB A/S	14-Apr-2025	3:37:50 PM	5	1265.00	AQEU
GENMAB A/S	14-Apr-2025	3:38:02 PM	84	1264.50	XCSE
GENMAB A/S	14-Apr-2025	3:38:02 PM	5	1265.00	AQEU
GENMAB A/S	14-Apr-2025	3:38:02 PM	2	1265.00	AQEU
GENMAB A/S	14-Apr-2025	3:38:02 PM	13	1265.00	AQEU
GENMAB A/S	14-Apr-2025	3:38:29 PM	85	1265.50	XCSE
GENMAB A/S	14-Apr-2025	3:38:29 PM	7	1265.50	CEUX
GENMAB A/S	14-Apr-2025	3:38:29 PM	38	1265.50	CEUX
GENMAB A/S	14-Apr-2025	3:38:29 PM	15	1265.50	CEUX
GENMAB A/S	14-Apr-2025	3:38:29 PM	15	1265.50	CEUX
GENMAB A/S	14-Apr-2025	3:38:29 PM	12	1265.50	CEUX
GENMAB A/S	14-Apr-2025	3:38:56 PM	84	1265.50	XCSE
GENMAB A/S	14-Apr-2025	3:38:56 PM	19	1265.50	XCSE
GENMAB A/S	14-Apr-2025	3:38:56 PM	40	1265.50	XCSE
GENMAB A/S	14-Apr-2025	3:38:56 PM	5	1265.50	XCSE
GENMAB A/S	14-Apr-2025	3:38:56 PM	9	1265.50	XCSE
GENMAB A/S	14-Apr-2025	3:38:56 PM	39	1265.50	XCSE
GENMAB A/S	14-Apr-2025	3:38:56 PM	34	1265.50	TQEX
GENMAB A/S	14-Apr-2025	3:38:56 PM	4	1264.50	CEUX
GENMAB A/S	14-Apr-2025	3:38:56 PM	15	1264.50	CEUX
GENMAB A/S	14-Apr-2025	3:38:56 PM	5	1264.50	CEUX
GENMAB A/S	14-Apr-2025	3:38:56 PM	20	1264.50	CEUX
GENMAB A/S	14-Apr-2025	3:39:39 PM	32	1267.00	CEUX
GENMAB A/S	14-Apr-2025	3:39:41 PM	35	1266.50	XCSE

Exhibit 99.1(a)

APPENDIX Share buy-back programme - Specification for April 14 – April 18, 2025

GENMAB A/S	14-Apr-2025	3:39:41 PM	49	1266.50	XCSE
GENMAB A/S	14-Apr-2025	3:39:41 PM	19	1266.50	XCSE
GENMAB A/S	14-Apr-2025	3:39:41 PM	10	1266.50	XCSE
GENMAB A/S	14-Apr-2025	3:39:41 PM	10	1266.50	XCSE
GENMAB A/S	14-Apr-2025	3:39:41 PM	11	1266.50	XCSE
GENMAB A/S	14-Apr-2025	3:39:41 PM	4	1266.00	AQEU
GENMAB A/S	14-Apr-2025	3:39:41 PM	4	1266.00	AQEU
GENMAB A/S	14-Apr-2025	3:39:41 PM	32	1266.50	CEUX
GENMAB A/S	14-Apr-2025	3:39:50 PM	35	1266.50	XCSE
GENMAB A/S	14-Apr-2025	3:39:50 PM	18	1266.50	XCSE
GENMAB A/S	14-Apr-2025	3:39:50 PM	40	1266.50	XCSE
GENMAB A/S	14-Apr-2025	3:39:50 PM	11	1266.50	XCSE
GENMAB A/S	14-Apr-2025	3:39:50 PM	8	1266.50	XCSE
GENMAB A/S	14-Apr-2025	3:39:50 PM	5	1266.50	XCSE
GENMAB A/S	14-Apr-2025	3:39:50 PM	11	1266.50	XCSE
GENMAB A/S	14-Apr-2025	3:39:50 PM	6	1266.50	XCSE
GENMAB A/S	14-Apr-2025	3:39:50 PM	10	1266.50	XCSE
GENMAB A/S	14-Apr-2025	3:39:50 PM	40	1266.50	XCSE
GENMAB A/S	14-Apr-2025	3:39:56 PM	1	1266.00	AQEU
GENMAB A/S	14-Apr-2025	3:39:59 PM	21	1266.00	AQEU
GENMAB A/S	14-Apr-2025	3:39:59 PM	32	1266.00	CEUX
GENMAB A/S	14-Apr-2025	3:40:09 PM	5	1266.50	XCSE
GENMAB A/S	14-Apr-2025	3:40:09 PM	40	1266.50	XCSE
GENMAB A/S	14-Apr-2025	3:40:09 PM	36	1266.50	XCSE
GENMAB A/S	14-Apr-2025	3:40:09 PM	24	1266.50	XCSE
GENMAB A/S	14-Apr-2025	3:40:09 PM	1	1266.50	XCSE
GENMAB A/S	14-Apr-2025	3:40:12 PM	34	1266.00	AQEU
GENMAB A/S	14-Apr-2025	3:40:13 PM	83	1265.50	XCSE
GENMAB A/S	14-Apr-2025	3:40:13 PM	2	1265.50	TQEX
GENMAB A/S	14-Apr-2025	3:40:13 PM	32	1266.00	CEUX
GENMAB A/S	14-Apr-2025	3:40:13 PM	5	1265.50	CEUX
GENMAB A/S	14-Apr-2025	3:40:14 PM	14	1265.50	TQEX
GENMAB A/S	14-Apr-2025	3:40:14 PM	15	1265.50	TQEX
GENMAB A/S	14-Apr-2025	3:40:14 PM	10	1265.50	CEUX
GENMAB A/S	14-Apr-2025	3:40:14 PM	11	1265.50	CEUX
GENMAB A/S	14-Apr-2025	3:40:14 PM	2	1265.50	CEUX
GENMAB A/S	14-Apr-2025	3:40:14 PM	3	1265.50	CEUX
GENMAB A/S	14-Apr-2025	3:40:14 PM	9	1265.50	CEUX
GENMAB A/S	14-Apr-2025	3:40:14 PM	15	1265.50	CEUX
GENMAB A/S	14-Apr-2025	3:40:14 PM	33	1265.50	CEUX
GENMAB A/S	14-Apr-2025	3:40:32 PM	84	1266.00	XCSE
GENMAB A/S	14-Apr-2025	3:40:32 PM	1	1266.00	XCSE
GENMAB A/S	14-Apr-2025	3:40:59 PM	4	1267.00	XCSE

Exhibit 99.1(a)

APPENDIX Share buy-back programme - Specification for April 14 – April 18, 2025

GENMAB A/S	14-Apr-2025	3:40:59 PM	27	1267.00	TQEX
GENMAB A/S	14-Apr-2025	3:40:59 PM	32	1267.00	CEUX
GENMAB A/S	14-Apr-2025	3:41:03 PM	35	1267.00	XCSE
GENMAB A/S	14-Apr-2025	3:41:03 PM	8	1267.00	XCSE
GENMAB A/S	14-Apr-2025	3:41:03 PM	13	1267.00	XCSE
GENMAB A/S	14-Apr-2025	3:41:03 PM	24	1267.00	XCSE
GENMAB A/S	14-Apr-2025	3:41:19 PM	83	1266.50	XCSE
GENMAB A/S	14-Apr-2025	3:41:33 PM	11	1267.00	XCSE
GENMAB A/S	14-Apr-2025	3:41:33 PM	14	1267.00	XCSE
GENMAB A/S	14-Apr-2025	3:41:33 PM	77	1266.50	CEUX
GENMAB A/S	14-Apr-2025	3:41:40 PM	8	1267.00	XCSE
GENMAB A/S	14-Apr-2025	3:41:45 PM	6	1267.00	TQEX
GENMAB A/S	14-Apr-2025	3:41:45 PM	10	1267.00	TQEX
GENMAB A/S	14-Apr-2025	3:41:45 PM	5	1267.00	TQEX
GENMAB A/S	14-Apr-2025	3:41:45 PM	5	1267.00	TQEX
GENMAB A/S	14-Apr-2025	3:42:06 PM	3	1266.50	XCSE
GENMAB A/S	14-Apr-2025	3:42:06 PM	1	1266.50	XCSE
GENMAB A/S	14-Apr-2025	3:42:06 PM	5	1266.50	XCSE
GENMAB A/S	14-Apr-2025	3:42:06 PM	3	1266.50	XCSE
GENMAB A/S	14-Apr-2025	3:42:06 PM	10	1266.50	XCSE
GENMAB A/S	14-Apr-2025	3:42:06 PM	2	1266.50	XCSE
GENMAB A/S	14-Apr-2025	3:42:06 PM	3	1266.50	XCSE
GENMAB A/S	14-Apr-2025	3:42:06 PM	4	1266.50	XCSE
GENMAB A/S	14-Apr-2025	3:42:06 PM	4	1266.50	XCSE
GENMAB A/S	14-Apr-2025	3:42:06 PM	10	1267.00	XCSE
GENMAB A/S	14-Apr-2025	3:42:06 PM	22	1267.00	XCSE
GENMAB A/S	14-Apr-2025	3:42:06 PM	35	1267.00	XCSE
GENMAB A/S	14-Apr-2025	3:42:06 PM	11	1267.00	XCSE
GENMAB A/S	14-Apr-2025	3:42:06 PM	11	1266.50	XCSE
GENMAB A/S	14-Apr-2025	3:42:06 PM	5	1266.50	XCSE
GENMAB A/S	14-Apr-2025	3:42:06 PM	5	1266.50	XCSE
GENMAB A/S	14-Apr-2025	3:42:06 PM	1	1266.50	XCSE
GENMAB A/S	14-Apr-2025	3:42:06 PM	2	1266.50	XCSE
GENMAB A/S	14-Apr-2025	3:42:06 PM	2	1266.50	XCSE
GENMAB A/S	14-Apr-2025	3:42:06 PM	3	1267.00	CEUX
GENMAB A/S	14-Apr-2025	3:42:06 PM	2	1267.00	CEUX
GENMAB A/S	14-Apr-2025	3:42:06 PM	3	1267.00	CEUX
GENMAB A/S	14-Apr-2025	3:42:06 PM	2	1267.00	CEUX
GENMAB A/S	14-Apr-2025	3:42:06 PM	2	1267.00	CEUX
GENMAB A/S	14-Apr-2025	3:42:06 PM	3	1267.00	CEUX
GENMAB A/S	14-Apr-2025	3:42:06 PM	10	1266.50	CEUX
GENMAB A/S	14-Apr-2025	3:42:06 PM	32	1266.50	CEUX
GENMAB A/S	14-Apr-2025	3:42:06 PM	15	1266.50	CEUX

Exhibit 99.1(a)

APPENDIX Share buy-back programme - Specification for April 14 – April 18, 2025

GENMAB A/S	14-Apr-2025	3:42:06 PM	40	1266.50	CEUX
GENMAB A/S	14-Apr-2025	3:42:06 PM	2	1266.50	CEUX
GENMAB A/S	14-Apr-2025	3:42:07 PM	63	1266.50	XCSE
GENMAB A/S	14-Apr-2025	3:42:11 PM	11	1266.50	CEUX
GENMAB A/S	14-Apr-2025	3:42:18 PM	87	1266.50	XCSE
GENMAB A/S	14-Apr-2025	3:42:18 PM	11	1266.50	CEUX
GENMAB A/S	14-Apr-2025	3:42:18 PM	61	1266.50	CEUX
GENMAB A/S	14-Apr-2025	3:42:18 PM	1	1266.50	CEUX
GENMAB A/S	14-Apr-2025	3:42:37 PM	84	1266.50	XCSE
GENMAB A/S	14-Apr-2025	3:42:37 PM	5	1266.50	TQEX
GENMAB A/S	14-Apr-2025	3:42:37 PM	2	1266.50	TQEX
GENMAB A/S	14-Apr-2025	3:42:37 PM	3	1266.50	TQEX
GENMAB A/S	14-Apr-2025	3:42:37 PM	2	1266.50	TQEX
GENMAB A/S	14-Apr-2025	3:42:37 PM	8	1266.50	TQEX
GENMAB A/S	14-Apr-2025	3:42:37 PM	4	1266.50	TQEX
GENMAB A/S	14-Apr-2025	3:42:37 PM	27	1267.00	AQEU
GENMAB A/S	14-Apr-2025	3:42:37 PM	7	1266.50	CEUX
GENMAB A/S	14-Apr-2025	3:42:37 PM	2	1266.50	CEUX
GENMAB A/S	14-Apr-2025	3:42:37 PM	12	1266.50	CEUX
GENMAB A/S	14-Apr-2025	3:42:37 PM	13	1266.50	CEUX
GENMAB A/S	14-Apr-2025	3:42:37 PM	7	1266.50	CEUX
GENMAB A/S	14-Apr-2025	3:42:37 PM	3	1266.50	CEUX
GENMAB A/S	14-Apr-2025	3:42:37 PM	11	1266.50	CEUX
GENMAB A/S	14-Apr-2025	3:43:16 PM	40	1267.50	XCSE
GENMAB A/S	14-Apr-2025	3:43:16 PM	13	1267.50	XCSE
GENMAB A/S	14-Apr-2025	3:43:16 PM	24	1267.50	XCSE
GENMAB A/S	14-Apr-2025	3:43:16 PM	74	1267.00	XCSE
GENMAB A/S	14-Apr-2025	3:43:16 PM	9	1267.00	XCSE
GENMAB A/S	14-Apr-2025	3:43:16 PM	28	1267.50	CEUX
GENMAB A/S	14-Apr-2025	3:43:16 PM	15	1267.50	CEUX
GENMAB A/S	14-Apr-2025	3:43:16 PM	41	1267.50	CEUX
GENMAB A/S	14-Apr-2025	3:43:32 PM	36	1267.00	XCSE
GENMAB A/S	14-Apr-2025	3:43:32 PM	26	1267.00	AQEU
GENMAB A/S	14-Apr-2025	3:43:40 PM	47	1267.00	XCSE
GENMAB A/S	14-Apr-2025	3:43:40 PM	12	1267.00	XCSE
GENMAB A/S	14-Apr-2025	3:43:40 PM	23	1267.00	XCSE
GENMAB A/S	14-Apr-2025	3:43:40 PM	11	1267.00	XCSE
GENMAB A/S	14-Apr-2025	3:43:40 PM	2	1267.00	XCSE
GENMAB A/S	14-Apr-2025	3:43:50 PM	55	1266.50	XCSE
GENMAB A/S	14-Apr-2025	3:43:50 PM	30	1266.50	XCSE
GENMAB A/S	14-Apr-2025	3:43:50 PM	15	1266.00	TQEX
GENMAB A/S	14-Apr-2025	3:43:50 PM	12	1266.00	TQEX
GENMAB A/S	14-Apr-2025	3:43:50 PM	4	1266.00	AQEU

Exhibit 99.1(a)

APPENDIX Share buy-back programme - Specification for April 14 – April 18, 2025

GENMAB A/S	14-Apr-2025	3:43:50 PM	9	1266.00	AQEU
GENMAB A/S	14-Apr-2025	3:43:50 PM	10	1266.00	AQEU
GENMAB A/S	14-Apr-2025	3:43:50 PM	15	1266.50	CEUX
GENMAB A/S	14-Apr-2025	3:43:50 PM	14	1266.50	CEUX
GENMAB A/S	14-Apr-2025	3:43:56 PM	85	1265.50	XCSE
GENMAB A/S	14-Apr-2025	3:43:56 PM	6	1265.50	CEUX
GENMAB A/S	14-Apr-2025	3:43:56 PM	76	1265.50	CEUX
GENMAB A/S	14-Apr-2025	3:44:08 PM	83	1265.50	XCSE
GENMAB A/S	14-Apr-2025	3:44:38 PM	27	1266.50	CEUX
GENMAB A/S	14-Apr-2025	3:44:55 PM	20	1266.50	CEUX
GENMAB A/S	14-Apr-2025	3:44:55 PM	39	1266.50	CEUX
GENMAB A/S	14-Apr-2025	3:44:56 PM	10	1266.50	XCSE
GENMAB A/S	14-Apr-2025	3:44:56 PM	8	1266.50	XCSE
GENMAB A/S	14-Apr-2025	3:44:56 PM	12	1266.50	XCSE
GENMAB A/S	14-Apr-2025	3:44:56 PM	12	1266.50	XCSE
GENMAB A/S	14-Apr-2025	3:44:56 PM	40	1266.50	XCSE
GENMAB A/S	14-Apr-2025	3:44:59 PM	83	1266.00	XCSE
GENMAB A/S	14-Apr-2025	3:45:44 PM	48	1266.50	XCSE
GENMAB A/S	14-Apr-2025	3:45:44 PM	37	1266.50	XCSE
GENMAB A/S	14-Apr-2025	3:45:44 PM	2	1267.00	AQEU
GENMAB A/S	14-Apr-2025	3:45:44 PM	25	1267.00	AQEU
GENMAB A/S	14-Apr-2025	3:45:44 PM	69	1266.50	CEUX
GENMAB A/S	14-Apr-2025	3:45:44 PM	13	1266.50	CEUX
GENMAB A/S	14-Apr-2025	3:45:45 PM	4	1266.50	CEUX
GENMAB A/S	14-Apr-2025	3:45:47 PM	25	1266.50	XCSE
GENMAB A/S	14-Apr-2025	3:45:48 PM	7	1266.50	XCSE
GENMAB A/S	14-Apr-2025	3:45:48 PM	11	1266.50	XCSE
GENMAB A/S	14-Apr-2025	3:45:48 PM	11	1266.50	XCSE
GENMAB A/S	14-Apr-2025	3:45:48 PM	4	1266.50	XCSE
GENMAB A/S	14-Apr-2025	3:45:51 PM	2	1266.00	TQEX
GENMAB A/S	14-Apr-2025	3:45:51 PM	23	1266.00	TQEX
GENMAB A/S	14-Apr-2025	3:45:51 PM	14	1266.00	AQEU
GENMAB A/S	14-Apr-2025	3:46:26 PM	8	1266.50	XCSE
GENMAB A/S	14-Apr-2025	3:46:33 PM	66	1266.50	CEUX
GENMAB A/S	14-Apr-2025	3:46:34 PM	23	1266.50	CEUX
GENMAB A/S	14-Apr-2025	3:46:37 PM	1	1266.50	XCSE
GENMAB A/S	14-Apr-2025	3:46:37 PM	1	1266.50	XCSE
GENMAB A/S	14-Apr-2025	3:46:37 PM	81	1266.50	XCSE
GENMAB A/S	14-Apr-2025	3:46:37 PM	23	1266.50	TQEX
GENMAB A/S	14-Apr-2025	3:46:37 PM	2	1266.50	TQEX
GENMAB A/S	14-Apr-2025	3:47:05 PM	50	1266.00	XCSE
GENMAB A/S	14-Apr-2025	3:47:05 PM	20	1266.00	XCSE
GENMAB A/S	14-Apr-2025	3:47:05 PM	33	1266.00	AQEU

Exhibit 99.1(a)

APPENDIX Share buy-back programme - Specification for April 14 – April 18, 2025

GENMAB A/S	14-Apr-2025	3:47:05 PM	36	1266.00	CEUX
GENMAB A/S	14-Apr-2025	3:47:05 PM	82	1265.50	CEUX
GENMAB A/S	14-Apr-2025	3:47:21 PM	35	1266.00	XCSE
GENMAB A/S	14-Apr-2025	3:47:21 PM	21	1266.00	XCSE
GENMAB A/S	14-Apr-2025	3:47:21 PM	40	1266.00	XCSE
GENMAB A/S	14-Apr-2025	3:47:21 PM	13	1266.00	XCSE
GENMAB A/S	14-Apr-2025	3:47:21 PM	3	1266.00	XCSE
GENMAB A/S	14-Apr-2025	3:47:21 PM	49	1266.00	XCSE
GENMAB A/S	14-Apr-2025	3:47:21 PM	3	1266.00	XCSE
GENMAB A/S	14-Apr-2025	3:47:21 PM	40	1266.00	XCSE
GENMAB A/S	14-Apr-2025	3:47:21 PM	11	1266.00	XCSE
GENMAB A/S	14-Apr-2025	3:47:21 PM	9	1266.00	XCSE
GENMAB A/S	14-Apr-2025	3:47:22 PM	23	1266.00	XCSE
GENMAB A/S	14-Apr-2025	3:47:22 PM	13	1266.00	XCSE
GENMAB A/S	14-Apr-2025	3:47:22 PM	12	1266.00	XCSE
GENMAB A/S	14-Apr-2025	3:47:22 PM	12	1266.00	XCSE
GENMAB A/S	14-Apr-2025	3:47:22 PM	40	1266.00	XCSE
GENMAB A/S	14-Apr-2025	3:47:23 PM	87	1265.50	XCSE
GENMAB A/S	14-Apr-2025	3:47:23 PM	25	1265.50	TQEX
GENMAB A/S	14-Apr-2025	3:47:23 PM	4	1264.50	TQEX
GENMAB A/S	14-Apr-2025	3:47:23 PM	4	1264.50	TQEX
GENMAB A/S	14-Apr-2025	3:47:23 PM	3	1264.50	TQEX
GENMAB A/S	14-Apr-2025	3:47:23 PM	2	1264.50	TQEX
GENMAB A/S	14-Apr-2025	3:47:23 PM	32	1265.50	CEUX
GENMAB A/S	14-Apr-2025	3:47:23 PM	59	1265.00	CEUX
GENMAB A/S	14-Apr-2025	3:48:07 PM	35	1267.50	XCSE
GENMAB A/S	14-Apr-2025	3:48:16 PM	16	1267.50	XCSE
GENMAB A/S	14-Apr-2025	3:48:16 PM	26	1267.50	XCSE
GENMAB A/S	14-Apr-2025	3:48:18 PM	7	1267.50	XCSE
GENMAB A/S	14-Apr-2025	3:48:49 PM	36	1267.50	CEUX
GENMAB A/S	14-Apr-2025	3:48:49 PM	2	1267.50	CEUX
GENMAB A/S	14-Apr-2025	3:48:49 PM	48	1267.50	CEUX
GENMAB A/S	14-Apr-2025	3:48:58 PM	89	1267.50	XCSE
GENMAB A/S	14-Apr-2025	3:48:58 PM	4	1267.00	TQEX
GENMAB A/S	14-Apr-2025	3:48:58 PM	2	1267.00	TQEX
GENMAB A/S	14-Apr-2025	3:48:58 PM	2	1267.00	TQEX
GENMAB A/S	14-Apr-2025	3:48:58 PM	2	1267.00	TQEX
GENMAB A/S	14-Apr-2025	3:48:58 PM	2	1267.00	TQEX
GENMAB A/S	14-Apr-2025	3:48:58 PM	2	1267.00	TQEX
GENMAB A/S	14-Apr-2025	3:48:58 PM	20	1267.00	TQEX
GENMAB A/S	14-Apr-2025	3:48:58 PM	33	1267.00	AQEU
GENMAB A/S	14-Apr-2025	3:48:58 PM	32	1267.00	CEUX
GENMAB A/S	14-Apr-2025	3:48:58 PM	2	1267.50	CEUX

Exhibit 99.1(a)

APPENDIX Share buy-back programme - Specification for April 14 – April 18, 2025

GENMAB A/S	14-Apr-2025	3:48:58 PM	4	1267.50	CEUX
GENMAB A/S	14-Apr-2025	3:48:58 PM	3	1267.50	CEUX
GENMAB A/S	14-Apr-2025	3:48:58 PM	21	1267.50	CEUX
GENMAB A/S	14-Apr-2025	3:48:58 PM	5	1267.50	CEUX
GENMAB A/S	14-Apr-2025	3:48:58 PM	5	1267.50	CEUX
GENMAB A/S	14-Apr-2025	3:48:58 PM	6	1267.50	CEUX
GENMAB A/S	14-Apr-2025	3:48:58 PM	3	1267.50	CEUX
GENMAB A/S	14-Apr-2025	3:48:58 PM	2	1267.50	CEUX
GENMAB A/S	14-Apr-2025	3:48:58 PM	4	1267.50	CEUX
GENMAB A/S	14-Apr-2025	3:48:58 PM	5	1267.50	CEUX
GENMAB A/S	14-Apr-2025	3:48:58 PM	3	1267.00	CEUX
GENMAB A/S	14-Apr-2025	3:48:58 PM	2	1267.00	CEUX
GENMAB A/S	14-Apr-2025	3:48:58 PM	50	1267.00	CEUX
GENMAB A/S	14-Apr-2025	3:48:59 PM	35	1267.50	XCSE
GENMAB A/S	14-Apr-2025	3:48:59 PM	21	1267.50	XCSE
GENMAB A/S	14-Apr-2025	3:48:59 PM	40	1267.50	XCSE
GENMAB A/S	14-Apr-2025	3:48:59 PM	12	1267.50	XCSE
GENMAB A/S	14-Apr-2025	3:48:59 PM	4	1267.50	XCSE
GENMAB A/S	14-Apr-2025	3:48:59 PM	8	1267.00	XCSE
GENMAB A/S	14-Apr-2025	3:48:59 PM	7	1267.50	XCSE
GENMAB A/S	14-Apr-2025	3:48:59 PM	12	1267.50	XCSE
GENMAB A/S	14-Apr-2025	3:48:59 PM	21	1267.50	XCSE
GENMAB A/S	14-Apr-2025	3:48:59 PM	40	1267.50	XCSE
GENMAB A/S	14-Apr-2025	3:48:59 PM	10	1267.50	XCSE
GENMAB A/S	14-Apr-2025	3:48:59 PM	14	1267.50	XCSE
GENMAB A/S	14-Apr-2025	3:49:03 PM	86	1267.00	CEUX
GENMAB A/S	14-Apr-2025	3:49:08 PM	87	1266.50	XCSE
GENMAB A/S	14-Apr-2025	3:49:56 PM	44	1269.00	XCSE
GENMAB A/S	14-Apr-2025	3:49:56 PM	42	1269.00	XCSE
GENMAB A/S	14-Apr-2025	3:50:07 PM	82	1269.50	CEUX
GENMAB A/S	14-Apr-2025	3:50:29 PM	12	1269.00	XCSE
GENMAB A/S	14-Apr-2025	3:50:29 PM	25	1269.00	XCSE
GENMAB A/S	14-Apr-2025	3:50:29 PM	12	1269.00	XCSE
GENMAB A/S	14-Apr-2025	3:50:29 PM	34	1269.00	XCSE
GENMAB A/S	14-Apr-2025	3:50:29 PM	5	1269.50	TQEX
GENMAB A/S	14-Apr-2025	3:50:29 PM	5	1269.50	TQEX
GENMAB A/S	14-Apr-2025	3:50:29 PM	5	1269.50	TQEX
GENMAB A/S	14-Apr-2025	3:50:29 PM	11	1269.50	TQEX
GENMAB A/S	14-Apr-2025	3:50:29 PM	11	1269.50	AQEU
GENMAB A/S	14-Apr-2025	3:50:29 PM	2	1269.50	AQEU
GENMAB A/S	14-Apr-2025	3:50:29 PM	18	1269.50	AQEU
GENMAB A/S	14-Apr-2025	3:50:35 PM	8	1269.00	XCSE
GENMAB A/S	14-Apr-2025	3:50:35 PM	11	1269.00	XCSE

Exhibit 99.1(a)

APPENDIX Share buy-back programme - Specification for April 14 – April 18, 2025

GENMAB A/S	14-Apr-2025	3:50:35 PM	1	1268.50	CEUX
GENMAB A/S	14-Apr-2025	3:50:36 PM	7	1269.00	XCSE
GENMAB A/S	14-Apr-2025	3:50:36 PM	3	1269.00	XCSE
GENMAB A/S	14-Apr-2025	3:50:43 PM	20	1269.00	XCSE
GENMAB A/S	14-Apr-2025	3:50:43 PM	40	1269.00	XCSE
GENMAB A/S	14-Apr-2025	3:50:43 PM	10	1269.00	XCSE
GENMAB A/S	14-Apr-2025	3:50:43 PM	12	1269.00	XCSE
GENMAB A/S	14-Apr-2025	3:50:43 PM	10	1269.00	XCSE
GENMAB A/S	14-Apr-2025	3:50:43 PM	84	1268.50	CEUX
GENMAB A/S	14-Apr-2025	3:50:44 PM	40	1268.50	XCSE
GENMAB A/S	14-Apr-2025	3:50:44 PM	15	1268.50	XCSE
GENMAB A/S	14-Apr-2025	3:50:44 PM	25	1268.50	AQEU
GENMAB A/S	14-Apr-2025	3:50:48 PM	31	1268.50	XCSE
GENMAB A/S	14-Apr-2025	3:50:49 PM	86	1268.00	XCSE
GENMAB A/S	14-Apr-2025	3:50:49 PM	3	1268.00	XCSE
GENMAB A/S	14-Apr-2025	3:50:49 PM	33	1268.00	TQEX
GENMAB A/S	14-Apr-2025	3:51:07 PM	67	1268.50	XCSE
GENMAB A/S	14-Apr-2025	3:51:28 PM	20	1268.50	XCSE
GENMAB A/S	14-Apr-2025	3:51:28 PM	11	1268.50	XCSE
GENMAB A/S	14-Apr-2025	3:51:28 PM	4	1268.00	TQEX
GENMAB A/S	14-Apr-2025	3:51:28 PM	2	1268.00	TQEX
GENMAB A/S	14-Apr-2025	3:51:28 PM	4	1268.00	TQEX
GENMAB A/S	14-Apr-2025	3:51:28 PM	4	1268.00	TQEX
GENMAB A/S	14-Apr-2025	3:51:28 PM	37	1268.50	AQEU
GENMAB A/S	14-Apr-2025	3:51:28 PM	36	1268.50	CEUX
GENMAB A/S	14-Apr-2025	3:51:28 PM	5	1268.00	CEUX
GENMAB A/S	14-Apr-2025	3:51:28 PM	34	1268.00	CEUX
GENMAB A/S	14-Apr-2025	3:51:28 PM	6	1268.00	CEUX
GENMAB A/S	14-Apr-2025	3:51:28 PM	30	1268.00	CEUX
GENMAB A/S	14-Apr-2025	3:51:28 PM	8	1268.00	CEUX
GENMAB A/S	14-Apr-2025	3:51:28 PM	1	1268.00	CEUX
GENMAB A/S	14-Apr-2025	3:51:52 PM	11	1268.00	XCSE
GENMAB A/S	14-Apr-2025	3:51:52 PM	10	1268.00	XCSE
GENMAB A/S	14-Apr-2025	3:51:52 PM	10	1268.00	XCSE
GENMAB A/S	14-Apr-2025	3:51:52 PM	40	1268.00	XCSE
GENMAB A/S	14-Apr-2025	3:51:54 PM	7	1267.50	XCSE
GENMAB A/S	14-Apr-2025	3:51:56 PM	10	1267.00	CEUX
GENMAB A/S	14-Apr-2025	3:51:56 PM	10	1267.00	CEUX
GENMAB A/S	14-Apr-2025	3:51:56 PM	65	1267.00	CEUX
GENMAB A/S	14-Apr-2025	3:52:00 PM	10	1267.50	XCSE
GENMAB A/S	14-Apr-2025	3:52:00 PM	13	1267.50	XCSE
GENMAB A/S	14-Apr-2025	3:52:00 PM	1	1267.50	XCSE
GENMAB A/S	14-Apr-2025	3:52:00 PM	12	1267.50	XCSE

Exhibit 99.1(a)

APPENDIX Share buy-back programme - Specification for April 14 – April 18, 2025

GENMAB A/S	14-Apr-2025	3:52:00 PM	40	1267.50	XCSE
GENMAB A/S	14-Apr-2025	3:52:00 PM	35	1267.50	XCSE
GENMAB A/S	14-Apr-2025	3:52:00 PM	1	1267.50	XCSE
GENMAB A/S	14-Apr-2025	3:52:00 PM	87	1267.00	XCSE
GENMAB A/S	14-Apr-2025	3:52:00 PM	1	1267.00	XCSE
GENMAB A/S	14-Apr-2025	3:52:17 PM	5	1267.00	TQEX
GENMAB A/S	14-Apr-2025	3:52:17 PM	5	1267.00	TQEX
GENMAB A/S	14-Apr-2025	3:52:17 PM	25	1267.00	TQEX
GENMAB A/S	14-Apr-2025	3:52:17 PM	2	1267.00	CEUX
GENMAB A/S	14-Apr-2025	3:52:17 PM	8	1267.00	CEUX
GENMAB A/S	14-Apr-2025	3:52:39 PM	84	1268.00	XCSE
GENMAB A/S	14-Apr-2025	3:52:40 PM	3	1267.50	AQEU
GENMAB A/S	14-Apr-2025	3:52:40 PM	2	1267.50	AQEU
GENMAB A/S	14-Apr-2025	3:52:40 PM	7	1267.50	AQEU
GENMAB A/S	14-Apr-2025	3:52:40 PM	13	1267.50	AQEU
GENMAB A/S	14-Apr-2025	3:52:40 PM	4	1267.50	AQEU
GENMAB A/S	14-Apr-2025	3:52:40 PM	2	1267.50	AQEU
GENMAB A/S	14-Apr-2025	3:52:40 PM	86	1268.00	CEUX
GENMAB A/S	14-Apr-2025	3:52:43 PM	85	1268.00	XCSE
GENMAB A/S	14-Apr-2025	3:52:43 PM	6	1268.00	XCSE
GENMAB A/S	14-Apr-2025	3:52:43 PM	10	1268.00	XCSE
GENMAB A/S	14-Apr-2025	3:52:43 PM	5	1268.00	XCSE
GENMAB A/S	14-Apr-2025	3:52:43 PM	4	1268.00	XCSE
GENMAB A/S	14-Apr-2025	3:52:43 PM	2	1267.00	CEUX
GENMAB A/S	14-Apr-2025	3:52:43 PM	20	1267.00	CEUX
GENMAB A/S	14-Apr-2025	3:52:43 PM	10	1267.00	CEUX
GENMAB A/S	14-Apr-2025	3:53:13 PM	32	1267.50	TQEX
GENMAB A/S	14-Apr-2025	3:53:41 PM	3	1268.00	CEUX
GENMAB A/S	14-Apr-2025	3:53:49 PM	84	1268.00	XCSE
GENMAB A/S	14-Apr-2025	3:54:02 PM	40	1268.00	XCSE
GENMAB A/S	14-Apr-2025	3:54:02 PM	13	1268.00	XCSE
GENMAB A/S	14-Apr-2025	3:54:02 PM	17	1268.00	XCSE
GENMAB A/S	14-Apr-2025	3:54:02 PM	7	1268.00	XCSE
GENMAB A/S	14-Apr-2025	3:54:02 PM	3	1268.00	XCSE
GENMAB A/S	14-Apr-2025	3:54:02 PM	5	1268.00	XCSE
GENMAB A/S	14-Apr-2025	3:54:02 PM	10	1268.00	XCSE
GENMAB A/S	14-Apr-2025	3:54:02 PM	15	1268.00	CEUX
GENMAB A/S	14-Apr-2025	3:54:13 PM	25	1268.50	TQEX
GENMAB A/S	14-Apr-2025	3:54:13 PM	82	1268.50	CEUX
GENMAB A/S	14-Apr-2025	3:54:13 PM	6	1268.50	CEUX
GENMAB A/S	14-Apr-2025	3:54:14 PM	5	1268.50	AQEU
GENMAB A/S	14-Apr-2025	3:54:14 PM	22	1268.50	AQEU
GENMAB A/S	14-Apr-2025	3:54:14 PM	32	1268.50	CEUX

Exhibit 99.1(a)

APPENDIX Share buy-back programme - Specification for April 14 – April 18, 2025

GENMAB A/S	14-Apr-2025	3:54:20 PM	49	1268.50	XCSE
GENMAB A/S	14-Apr-2025	3:54:20 PM	63	1268.50	XCSE
GENMAB A/S	14-Apr-2025	3:54:21 PM	23	1268.50	XCSE
GENMAB A/S	14-Apr-2025	3:54:21 PM	20	1268.50	XCSE
GENMAB A/S	14-Apr-2025	3:54:22 PM	10	1268.50	XCSE
GENMAB A/S	14-Apr-2025	3:54:22 PM	5	1268.50	XCSE
GENMAB A/S	14-Apr-2025	3:54:22 PM	40	1268.50	XCSE
GENMAB A/S	14-Apr-2025	3:54:22 PM	11	1268.50	XCSE
GENMAB A/S	14-Apr-2025	3:54:22 PM	10	1268.50	XCSE
GENMAB A/S	14-Apr-2025	3:54:36 PM	7	1268.50	XCSE
GENMAB A/S	14-Apr-2025	3:54:36 PM	2	1268.50	XCSE
GENMAB A/S	14-Apr-2025	3:54:36 PM	3	1268.50	XCSE
GENMAB A/S	14-Apr-2025	3:54:36 PM	4	1268.50	XCSE
GENMAB A/S	14-Apr-2025	3:54:36 PM	4	1268.50	XCSE
GENMAB A/S	14-Apr-2025	3:54:36 PM	60	1268.00	XCSE
GENMAB A/S	14-Apr-2025	3:54:36 PM	4	1268.50	CEUX
GENMAB A/S	14-Apr-2025	3:54:38 PM	4	1268.00	CEUX
GENMAB A/S	14-Apr-2025	3:54:38 PM	8	1268.00	CEUX
GENMAB A/S	14-Apr-2025	3:54:38 PM	21	1268.00	CEUX
GENMAB A/S	14-Apr-2025	3:54:38 PM	7	1268.00	CEUX
GENMAB A/S	14-Apr-2025	3:54:38 PM	5	1268.00	CEUX
GENMAB A/S	14-Apr-2025	3:54:40 PM	44	1268.00	XCSE
GENMAB A/S	14-Apr-2025	3:54:58 PM	53	1268.50	XCSE
GENMAB A/S	14-Apr-2025	3:54:58 PM	36	1268.50	XCSE
GENMAB A/S	14-Apr-2025	3:54:58 PM	8	1268.50	AQEU
GENMAB A/S	14-Apr-2025	3:54:58 PM	21	1268.50	AQEU
GENMAB A/S	14-Apr-2025	3:55:00 PM	1	1268.50	AQEU
GENMAB A/S	14-Apr-2025	3:55:00 PM	6	1268.50	CEUX
GENMAB A/S	14-Apr-2025	3:55:00 PM	8	1268.50	CEUX
GENMAB A/S	14-Apr-2025	3:55:00 PM	21	1268.50	CEUX
GENMAB A/S	14-Apr-2025	3:55:00 PM	1	1268.50	CEUX
GENMAB A/S	14-Apr-2025	3:55:10 PM	26	1268.50	XCSE
GENMAB A/S	14-Apr-2025	3:55:10 PM	74	1268.50	XCSE
GENMAB A/S	14-Apr-2025	3:55:11 PM	10	1268.00	CEUX
GENMAB A/S	14-Apr-2025	3:55:11 PM	60	1268.00	CEUX
GENMAB A/S	14-Apr-2025	3:55:11 PM	10	1268.00	CEUX
GENMAB A/S	14-Apr-2025	3:55:11 PM	7	1268.00	CEUX
GENMAB A/S	14-Apr-2025	3:55:36 PM	11	1268.00	XCSE
GENMAB A/S	14-Apr-2025	3:55:36 PM	12	1268.00	XCSE
GENMAB A/S	14-Apr-2025	3:55:36 PM	11	1268.00	XCSE
GENMAB A/S	14-Apr-2025	3:55:36 PM	32	1268.00	XCSE
GENMAB A/S	14-Apr-2025	3:55:39 PM	32	1268.00	CEUX
GENMAB A/S	14-Apr-2025	3:55:42 PM	3	1267.50	AQEU

Exhibit 99.1(a)

APPENDIX Share buy-back programme - Specification for April 14 – April 18, 2025

GENMAB A/S	14-Apr-2025	3:56:09 PM	7	1267.00	XCSE
GENMAB A/S	14-Apr-2025	3:56:09 PM	1	1267.00	XCSE
GENMAB A/S	14-Apr-2025	3:56:09 PM	20	1267.00	XCSE
GENMAB A/S	14-Apr-2025	3:56:09 PM	53	1267.00	XCSE
GENMAB A/S	14-Apr-2025	3:56:09 PM	7	1267.00	XCSE
GENMAB A/S	14-Apr-2025	3:56:09 PM	40	1267.50	XCSE
GENMAB A/S	14-Apr-2025	3:56:09 PM	13	1267.50	XCSE
GENMAB A/S	14-Apr-2025	3:56:09 PM	35	1267.50	XCSE
GENMAB A/S	14-Apr-2025	3:56:09 PM	12	1267.50	XCSE
GENMAB A/S	14-Apr-2025	3:56:09 PM	12	1267.50	XCSE
GENMAB A/S	14-Apr-2025	3:56:09 PM	17	1267.00	TQEX
GENMAB A/S	14-Apr-2025	3:56:09 PM	13	1267.00	TQEX
GENMAB A/S	14-Apr-2025	3:56:09 PM	25	1267.50	AQEU
GENMAB A/S	14-Apr-2025	3:56:09 PM	3	1267.00	CEUX
GENMAB A/S	14-Apr-2025	3:56:09 PM	10	1267.00	CEUX
GENMAB A/S	14-Apr-2025	3:56:09 PM	15	1267.00	CEUX
GENMAB A/S	14-Apr-2025	3:56:09 PM	9	1267.00	CEUX
GENMAB A/S	14-Apr-2025	3:56:09 PM	4	1267.00	CEUX
GENMAB A/S	14-Apr-2025	3:56:10 PM	89	1267.00	CEUX
GENMAB A/S	14-Apr-2025	3:56:31 PM	40	1267.50	XCSE
GENMAB A/S	14-Apr-2025	3:56:31 PM	21	1267.50	XCSE
GENMAB A/S	14-Apr-2025	3:56:31 PM	11	1267.50	XCSE
GENMAB A/S	14-Apr-2025	3:56:31 PM	10	1267.50	XCSE
GENMAB A/S	14-Apr-2025	3:56:31 PM	12	1267.50	XCSE
GENMAB A/S	14-Apr-2025	3:56:31 PM	83	1267.00	XCSE
GENMAB A/S	14-Apr-2025	3:56:31 PM	18	1267.50	XCSE
GENMAB A/S	14-Apr-2025	3:56:31 PM	8	1267.50	TQEX
GENMAB A/S	14-Apr-2025	3:56:31 PM	20	1267.50	TQEX
GENMAB A/S	14-Apr-2025	3:56:37 PM	13	1267.00	CEUX
GENMAB A/S	14-Apr-2025	3:56:37 PM	21	1267.00	CEUX
GENMAB A/S	14-Apr-2025	3:56:37 PM	1	1267.00	CEUX
GENMAB A/S	14-Apr-2025	3:56:40 PM	20	1266.00	CEUX
GENMAB A/S	14-Apr-2025	3:56:40 PM	10	1266.00	CEUX
GENMAB A/S	14-Apr-2025	3:56:40 PM	10	1266.00	CEUX
GENMAB A/S	14-Apr-2025	3:56:40 PM	10	1266.00	CEUX
GENMAB A/S	14-Apr-2025	3:56:41 PM	85	1266.00	XCSE
GENMAB A/S	14-Apr-2025	3:56:41 PM	37	1266.00	CEUX
GENMAB A/S	14-Apr-2025	3:56:53 PM	25	1266.50	TQEX
GENMAB A/S	14-Apr-2025	3:56:53 PM	1	1266.00	CEUX
GENMAB A/S	14-Apr-2025	3:56:53 PM	14	1266.00	CEUX
GENMAB A/S	14-Apr-2025	3:56:53 PM	11	1266.00	CEUX
GENMAB A/S	14-Apr-2025	3:57:09 PM	89	1266.00	XCSE
GENMAB A/S	14-Apr-2025	3:57:09 PM	8	1266.00	AQEU

Exhibit 99.1(a)

APPENDIX Share buy-back programme - Specification for April 14 – April 18, 2025

GENMAB A/S	14-Apr-2025	3:57:09 PM	5	1266.00	AQEU
GENMAB A/S	14-Apr-2025	3:57:09 PM	12	1266.00	AQEU
GENMAB A/S	14-Apr-2025	3:57:09 PM	14	1266.00	CEUX
GENMAB A/S	14-Apr-2025	3:57:09 PM	39	1266.00	CEUX
GENMAB A/S	14-Apr-2025	3:57:09 PM	3	1266.00	CEUX
GENMAB A/S	14-Apr-2025	3:57:27 PM	16	1266.50	XCSE
GENMAB A/S	14-Apr-2025	3:57:27 PM	20	1266.50	XCSE
GENMAB A/S	14-Apr-2025	3:57:27 PM	10	1266.50	XCSE
GENMAB A/S	14-Apr-2025	3:57:27 PM	28	1266.50	XCSE
GENMAB A/S	14-Apr-2025	3:57:50 PM	2	1267.50	XCSE
GENMAB A/S	14-Apr-2025	3:57:50 PM	6	1267.50	XCSE
GENMAB A/S	14-Apr-2025	3:57:50 PM	25	1267.50	XCSE
GENMAB A/S	14-Apr-2025	3:57:50 PM	2	1267.50	XCSE
GENMAB A/S	14-Apr-2025	3:58:03 PM	4	1268.00	AQEU
GENMAB A/S	14-Apr-2025	3:58:03 PM	10	1268.00	AQEU
GENMAB A/S	14-Apr-2025	3:58:11 PM	45	1268.50	XCSE
GENMAB A/S	14-Apr-2025	3:58:11 PM	34	1268.50	CEUX
GENMAB A/S	14-Apr-2025	3:58:44 PM	27	1269.00	AQEU
GENMAB A/S	14-Apr-2025	3:58:44 PM	36	1269.00	CEUX
GENMAB A/S	14-Apr-2025	3:58:49 PM	2	1269.50	CEUX
GENMAB A/S	14-Apr-2025	3:58:57 PM	84	1269.50	XCSE
GENMAB A/S	14-Apr-2025	3:58:57 PM	83	1269.50	CEUX
GENMAB A/S	14-Apr-2025	3:59:09 PM	2	1269.00	XCSE
GENMAB A/S	14-Apr-2025	3:59:09 PM	3	1268.50	TQEX
GENMAB A/S	14-Apr-2025	3:59:09 PM	32	1269.00	CEUX
GENMAB A/S	14-Apr-2025	3:59:12 PM	40	1269.00	XCSE
GENMAB A/S	14-Apr-2025	3:59:12 PM	13	1269.00	XCSE
GENMAB A/S	14-Apr-2025	3:59:12 PM	12	1269.00	XCSE
GENMAB A/S	14-Apr-2025	3:59:12 PM	11	1269.00	XCSE
GENMAB A/S	14-Apr-2025	3:59:12 PM	5	1268.50	TQEX
GENMAB A/S	14-Apr-2025	3:59:12 PM	5	1268.50	TQEX
GENMAB A/S	14-Apr-2025	3:59:12 PM	50	1268.50	CEUX
GENMAB A/S	14-Apr-2025	3:59:13 PM	10	1269.00	XCSE
GENMAB A/S	14-Apr-2025	3:59:13 PM	40	1269.00	XCSE
GENMAB A/S	14-Apr-2025	3:59:13 PM	10	1269.00	XCSE
GENMAB A/S	14-Apr-2025	3:59:13 PM	12	1269.00	XCSE
GENMAB A/S	14-Apr-2025	3:59:13 PM	40	1269.00	XCSE
GENMAB A/S	14-Apr-2025	3:59:13 PM	13	1269.00	XCSE
GENMAB A/S	14-Apr-2025	3:59:13 PM	13	1269.00	XCSE
GENMAB A/S	14-Apr-2025	3:59:13 PM	29	1269.00	XCSE
GENMAB A/S	14-Apr-2025	3:59:20 PM	12	1269.00	XCSE
GENMAB A/S	14-Apr-2025	3:59:20 PM	11	1269.00	XCSE
GENMAB A/S	14-Apr-2025	3:59:20 PM	40	1269.00	XCSE

Exhibit 99.1(a)

APPENDIX Share buy-back programme - Specification for April 14 – April 18, 2025

GENMAB A/S	14-Apr-2025	3:59:20 PM	4	1269.00	XCSE
GENMAB A/S	14-Apr-2025	3:59:30 PM	40	1269.00	XCSE
GENMAB A/S	14-Apr-2025	3:59:30 PM	5	1269.00	XCSE
GENMAB A/S	14-Apr-2025	3:59:43 PM	7	1269.50	XCSE
GENMAB A/S	14-Apr-2025	3:59:47 PM	14	1269.50	TQEX
GENMAB A/S	14-Apr-2025	3:59:47 PM	5	1269.50	TQEX
GENMAB A/S	14-Apr-2025	3:59:47 PM	8	1269.50	TQEX
GENMAB A/S	14-Apr-2025	3:59:59 PM	64	1269.50	XCSE
GENMAB A/S	14-Apr-2025	3:59:59 PM	20	1269.50	XCSE
GENMAB A/S	14-Apr-2025	3:59:59 PM	3	1269.50	XCSE
GENMAB A/S	14-Apr-2025	3:59:59 PM	13	1269.50	XCSE
GENMAB A/S	14-Apr-2025	3:59:59 PM	9	1269.50	XCSE
GENMAB A/S	14-Apr-2025	3:59:59 PM	2	1269.50	TQEX
GENMAB A/S	14-Apr-2025	3:59:59 PM	3	1268.50	TQEX
GENMAB A/S	14-Apr-2025	3:59:59 PM	2	1269.00	AQEU
GENMAB A/S	14-Apr-2025	3:59:59 PM	9	1269.00	AQEU
GENMAB A/S	14-Apr-2025	3:59:59 PM	4	1269.00	AQEU
GENMAB A/S	14-Apr-2025	3:59:59 PM	4	1269.00	AQEU
GENMAB A/S	14-Apr-2025	3:59:59 PM	2	1269.00	AQEU
GENMAB A/S	14-Apr-2025	3:59:59 PM	4	1269.00	AQEU
GENMAB A/S	14-Apr-2025	3:59:59 PM	11	1269.00	CEUX
GENMAB A/S	14-Apr-2025	3:59:59 PM	31	1269.00	CEUX
GENMAB A/S	14-Apr-2025	3:59:59 PM	43	1269.00	CEUX
GENMAB A/S	14-Apr-2025	4:00:08 PM	32	1270.50	CEUX
GENMAB A/S	14-Apr-2025	4:00:08 PM	82	1270.00	CEUX
GENMAB A/S	14-Apr-2025	4:00:10 PM	26	1270.00	AQEU
GENMAB A/S	14-Apr-2025	4:00:22 PM	66	1270.00	CEUX
GENMAB A/S	14-Apr-2025	4:00:23 PM	82	1269.50	XCSE
GENMAB A/S	14-Apr-2025	4:00:23 PM	9	1269.50	TQEX
GENMAB A/S	14-Apr-2025	4:00:23 PM	10	1270.00	CEUX
GENMAB A/S	14-Apr-2025	4:00:23 PM	9	1270.00	CEUX
GENMAB A/S	14-Apr-2025	4:00:28 PM	31	1269.50	XCSE
GENMAB A/S	14-Apr-2025	4:00:28 PM	50	1269.50	XCSE
GENMAB A/S	14-Apr-2025	4:00:28 PM	2	1269.50	XCSE
GENMAB A/S	14-Apr-2025	4:00:28 PM	2	1269.50	XCSE
GENMAB A/S	14-Apr-2025	4:00:28 PM	2	1269.50	XCSE
GENMAB A/S	14-Apr-2025	4:00:43 PM	89	1269.00	CEUX
GENMAB A/S	14-Apr-2025	4:00:46 PM	36	1269.00	XCSE
GENMAB A/S	14-Apr-2025	4:00:46 PM	45	1269.00	XCSE
GENMAB A/S	14-Apr-2025	4:00:59 PM	4	1268.50	XCSE
GENMAB A/S	14-Apr-2025	4:00:59 PM	40	1268.50	XCSE
GENMAB A/S	14-Apr-2025	4:00:59 PM	3	1267.50	XCSE
GENMAB A/S	14-Apr-2025	4:00:59 PM	13	1267.50	XCSE

Exhibit 99.1(a)

APPENDIX Share buy-back programme - Specification for April 14 – April 18, 2025

GENMAB A/S	14-Apr-2025	4:00:59 PM	7	1267.50	XCSE
GENMAB A/S	14-Apr-2025	4:00:59 PM	3	1267.50	XCSE
GENMAB A/S	14-Apr-2025	4:00:59 PM	7	1267.50	XCSE
GENMAB A/S	14-Apr-2025	4:00:59 PM	5	1267.50	XCSE
GENMAB A/S	14-Apr-2025	4:00:59 PM	3	1267.50	XCSE
GENMAB A/S	14-Apr-2025	4:00:59 PM	13	1267.50	XCSE
GENMAB A/S	14-Apr-2025	4:00:59 PM	9	1268.50	TQEX
GENMAB A/S	14-Apr-2025	4:00:59 PM	1	1268.00	CEUX
GENMAB A/S	14-Apr-2025	4:00:59 PM	50	1268.00	CEUX
GENMAB A/S	14-Apr-2025	4:00:59 PM	36	1268.00	CEUX
GENMAB A/S	14-Apr-2025	4:01:08 PM	84	1267.00	XCSE
GENMAB A/S	14-Apr-2025	4:01:09 PM	22	1267.00	TQEX
GENMAB A/S	14-Apr-2025	4:01:11 PM	2	1266.50	CEUX
GENMAB A/S	14-Apr-2025	4:01:11 PM	11	1266.50	CEUX
GENMAB A/S	14-Apr-2025	4:01:11 PM	5	1266.50	CEUX
GENMAB A/S	14-Apr-2025	4:01:11 PM	49	1266.50	CEUX
GENMAB A/S	14-Apr-2025	4:01:37 PM	25	1268.50	XCSE
GENMAB A/S	14-Apr-2025	4:01:37 PM	13	1268.50	XCSE
GENMAB A/S	14-Apr-2025	4:01:37 PM	13	1268.50	XCSE
GENMAB A/S	14-Apr-2025	4:01:37 PM	11	1268.50	XCSE
GENMAB A/S	14-Apr-2025	4:01:37 PM	8	1268.50	XCSE
GENMAB A/S	14-Apr-2025	4:01:37 PM	4	1268.00	CEUX
GENMAB A/S	14-Apr-2025	4:01:37 PM	16	1268.00	CEUX
GENMAB A/S	14-Apr-2025	4:01:37 PM	7	1268.00	CEUX
GENMAB A/S	14-Apr-2025	4:01:37 PM	13	1268.00	CEUX
GENMAB A/S	14-Apr-2025	4:01:48 PM	1	1268.00	XCSE
GENMAB A/S	14-Apr-2025	4:01:48 PM	85	1268.00	XCSE
GENMAB A/S	14-Apr-2025	4:01:48 PM	8	1267.00	XCSE
GENMAB A/S	14-Apr-2025	4:01:48 PM	5	1267.50	TQEX
GENMAB A/S	14-Apr-2025	4:01:48 PM	15	1267.50	TQEX
GENMAB A/S	14-Apr-2025	4:01:48 PM	10	1267.50	TQEX
GENMAB A/S	14-Apr-2025	4:01:48 PM	4	1267.50	TQEX
GENMAB A/S	14-Apr-2025	4:01:48 PM	45	1268.00	AQEU
GENMAB A/S	14-Apr-2025	4:01:48 PM	33	1268.00	CEUX
GENMAB A/S	14-Apr-2025	4:01:58 PM	13	1267.00	XCSE
GENMAB A/S	14-Apr-2025	4:01:58 PM	52	1267.00	XCSE
GENMAB A/S	14-Apr-2025	4:01:59 PM	11	1267.00	XCSE
GENMAB A/S	14-Apr-2025	4:01:59 PM	3	1267.00	XCSE
GENMAB A/S	14-Apr-2025	4:02:31 PM	80	1267.50	XCSE
GENMAB A/S	14-Apr-2025	4:02:32 PM	8	1267.50	XCSE
GENMAB A/S	14-Apr-2025	4:02:49 PM	4	1268.00	CEUX
GENMAB A/S	14-Apr-2025	4:02:51 PM	35	1268.00	XCSE
GENMAB A/S	14-Apr-2025	4:02:51 PM	83	1268.00	CEUX

Exhibit 99.1(a)

APPENDIX Share buy-back programme - Specification for April 14 – April 18, 2025

GENMAB A/S	14-Apr-2025	4:03:05 PM	1	1267.50	XCSE
GENMAB A/S	14-Apr-2025	4:03:05 PM	87	1266.00	XCSE
GENMAB A/S	14-Apr-2025	4:03:05 PM	84	1265.00	XCSE
GENMAB A/S	14-Apr-2025	4:03:05 PM	89	1264.50	XCSE
GENMAB A/S	14-Apr-2025	4:03:05 PM	85	1263.50	XCSE
GENMAB A/S	14-Apr-2025	4:03:05 PM	82	1262.50	XCSE
GENMAB A/S	14-Apr-2025	4:03:05 PM	83	1261.00	XCSE
GENMAB A/S	14-Apr-2025	4:03:05 PM	16	1266.50	CEUX
GENMAB A/S	14-Apr-2025	4:03:05 PM	88	1265.50	CEUX
GENMAB A/S	14-Apr-2025	4:03:05 PM	84	1264.00	CEUX
GENMAB A/S	14-Apr-2025	4:03:05 PM	26	1265.50	CEUX
GENMAB A/S	14-Apr-2025	4:03:05 PM	26	1264.50	CEUX
GENMAB A/S	14-Apr-2025	4:03:05 PM	48	1263.50	CEUX
GENMAB A/S	14-Apr-2025	4:03:06 PM	20	1264.00	CEUX
GENMAB A/S	14-Apr-2025	4:03:06 PM	10	1264.00	CEUX
GENMAB A/S	14-Apr-2025	4:03:06 PM	5	1264.00	CEUX
GENMAB A/S	14-Apr-2025	4:03:09 PM	46	1264.50	XCSE
GENMAB A/S	14-Apr-2025	4:03:20 PM	4	1264.00	XCSE
GENMAB A/S	14-Apr-2025	4:03:20 PM	4	1264.00	XCSE
GENMAB A/S	14-Apr-2025	4:03:20 PM	18	1264.00	XCSE
GENMAB A/S	14-Apr-2025	4:03:29 PM	2	1264.00	XCSE
GENMAB A/S	14-Apr-2025	4:03:29 PM	2	1264.00	XCSE
GENMAB A/S	14-Apr-2025	4:03:49 PM	26	1266.00	TQEX
GENMAB A/S	14-Apr-2025	4:04:32 PM	2	1265.00	TQEX
GENMAB A/S	14-Apr-2025	4:05:07 PM	65	1265.00	XCSE
GENMAB A/S	14-Apr-2025	4:05:07 PM	22	1265.50	XCSE
GENMAB A/S	14-Apr-2025	4:05:07 PM	40	1265.50	XCSE
GENMAB A/S	14-Apr-2025	4:05:07 PM	4	1265.50	XCSE
GENMAB A/S	14-Apr-2025	4:05:07 PM	8	1265.50	XCSE
GENMAB A/S	14-Apr-2025	4:05:07 PM	13	1265.50	XCSE
GENMAB A/S	14-Apr-2025	4:05:07 PM	2	1265.00	TQEX
GENMAB A/S	14-Apr-2025	4:05:07 PM	3	1265.00	TQEX
GENMAB A/S	14-Apr-2025	4:05:07 PM	2	1265.00	TQEX
GENMAB A/S	14-Apr-2025	4:05:07 PM	5	1265.00	TQEX
GENMAB A/S	14-Apr-2025	4:05:07 PM	2	1265.00	TQEX
GENMAB A/S	14-Apr-2025	4:05:07 PM	8	1265.00	TQEX
GENMAB A/S	14-Apr-2025	4:05:07 PM	2	1265.00	TQEX
GENMAB A/S	14-Apr-2025	4:05:07 PM	25	1265.00	AQEU
GENMAB A/S	14-Apr-2025	4:05:07 PM	37	1265.00	CEUX
GENMAB A/S	14-Apr-2025	4:05:09 PM	22	1265.50	TQEX
GENMAB A/S	14-Apr-2025	4:05:39 PM	85	1266.00	XCSE
GENMAB A/S	14-Apr-2025	4:07:14 PM	100	1268.50	XCSE
GENMAB A/S	14-Apr-2025	4:07:14 PM	36	1268.50	CEUX

Exhibit 99.1(a)

APPENDIX Share buy-back programme - Specification for April 14 – April 18, 2025

GENMAB A/S	14-Apr-2025	4:07:15 PM	67	1268.00	XCSE
GENMAB A/S	14-Apr-2025	4:07:33 PM	17	1268.00	XCSE
GENMAB A/S	14-Apr-2025	4:07:33 PM	10	1268.00	XCSE
GENMAB A/S	14-Apr-2025	4:07:33 PM	27	1268.00	XCSE
GENMAB A/S	14-Apr-2025	4:07:33 PM	31	1268.00	AQEU
GENMAB A/S	14-Apr-2025	4:07:33 PM	54	1268.00	CEUX
GENMAB A/S	14-Apr-2025	4:07:33 PM	35	1268.00	CEUX
GENMAB A/S	14-Apr-2025	4:07:33 PM	20	1268.00	CEUX
GENMAB A/S	14-Apr-2025	4:07:59 PM	82	1267.50	XCSE
GENMAB A/S	14-Apr-2025	4:08:03 PM	40	1267.50	XCSE
GENMAB A/S	14-Apr-2025	4:08:03 PM	13	1267.50	XCSE
GENMAB A/S	14-Apr-2025	4:08:03 PM	11	1267.50	XCSE
GENMAB A/S	14-Apr-2025	4:08:03 PM	12	1267.50	XCSE
GENMAB A/S	14-Apr-2025	4:08:03 PM	12	1267.50	XCSE
GENMAB A/S	14-Apr-2025	4:08:03 PM	12	1267.50	XCSE
GENMAB A/S	14-Apr-2025	4:08:03 PM	40	1267.00	TQEX
GENMAB A/S	14-Apr-2025	4:08:03 PM	3	1267.00	TQEX
GENMAB A/S	14-Apr-2025	4:08:03 PM	5	1267.00	AQEU
GENMAB A/S	14-Apr-2025	4:08:03 PM	84	1267.00	CEUX
GENMAB A/S	14-Apr-2025	4:08:04 PM	11	1267.50	XCSE
GENMAB A/S	14-Apr-2025	4:08:04 PM	11	1267.50	XCSE
GENMAB A/S	14-Apr-2025	4:08:04 PM	11	1267.50	XCSE
GENMAB A/S	14-Apr-2025	4:08:04 PM	11	1267.50	XCSE
GENMAB A/S	14-Apr-2025	4:08:04 PM	21	1267.50	XCSE
GENMAB A/S	14-Apr-2025	4:08:04 PM	12	1267.50	XCSE
GENMAB A/S	14-Apr-2025	4:08:04 PM	12	1267.50	XCSE
GENMAB A/S	14-Apr-2025	4:08:04 PM	12	1267.50	XCSE
GENMAB A/S	14-Apr-2025	4:08:04 PM	17	1267.50	XCSE
GENMAB A/S	14-Apr-2025	4:08:04 PM	59	1267.50	XCSE
GENMAB A/S	14-Apr-2025	4:08:04 PM	112	1267.50	XCSE
GENMAB A/S	14-Apr-2025	4:08:18 PM	36	1267.00	XCSE
GENMAB A/S	14-Apr-2025	4:08:18 PM	88	1266.50	XCSE
GENMAB A/S	14-Apr-2025	4:08:18 PM	1	1266.50	XCSE
GENMAB A/S	14-Apr-2025	4:08:18 PM	20	1267.00	AQEU
GENMAB A/S	14-Apr-2025	4:08:18 PM	36	1267.00	CEUX
GENMAB A/S	14-Apr-2025	4:09:09 PM	83	1266.50	XCSE
GENMAB A/S	14-Apr-2025	4:09:13 PM	25	1266.50	TQEX
GENMAB A/S	14-Apr-2025	4:09:13 PM	60	1266.00	CEUX
GENMAB A/S	14-Apr-2025	4:09:24 PM	5	1266.50	CEUX
GENMAB A/S	14-Apr-2025	4:09:24 PM	6	1266.50	CEUX
GENMAB A/S	14-Apr-2025	4:09:24 PM	5	1267.00	CEUX
GENMAB A/S	14-Apr-2025	4:09:24 PM	61	1267.00	CEUX
GENMAB A/S	14-Apr-2025	4:09:24 PM	19	1267.00	CEUX

Exhibit 99.1(a)

APPENDIX Share buy-back programme - Specification for April 14 – April 18, 2025

GENMAB A/S	14-Apr-2025	4:09:26 PM	40	1267.00	XCSE
GENMAB A/S	14-Apr-2025	4:09:26 PM	13	1267.00	XCSE
GENMAB A/S	14-Apr-2025	4:09:26 PM	11	1267.00	XCSE
GENMAB A/S	14-Apr-2025	4:09:26 PM	12	1267.00	XCSE
GENMAB A/S	14-Apr-2025	4:10:19 PM	23	1267.00	AQEU
GENMAB A/S	14-Apr-2025	4:10:19 PM	86	1267.00	CEUX
GENMAB A/S	14-Apr-2025	4:10:19 PM	36	1267.00	CEUX
GENMAB A/S	14-Apr-2025	4:10:20 PM	40	1267.00	XCSE
GENMAB A/S	14-Apr-2025	4:10:20 PM	13	1267.00	XCSE
GENMAB A/S	14-Apr-2025	4:10:20 PM	26	1266.50	TQEX
GENMAB A/S	14-Apr-2025	4:10:20 PM	4	1267.00	AQEU
GENMAB A/S	14-Apr-2025	4:10:21 PM	49	1267.00	XCSE
GENMAB A/S	14-Apr-2025	4:10:23 PM	100	1267.00	XCSE
GENMAB A/S	14-Apr-2025	4:10:33 PM	86	1266.00	XCSE
GENMAB A/S	14-Apr-2025	4:10:33 PM	5	1265.00	XCSE
GENMAB A/S	14-Apr-2025	4:10:33 PM	28	1266.00	AQEU
GENMAB A/S	14-Apr-2025	4:10:33 PM	28	1266.00	CEUX
GENMAB A/S	14-Apr-2025	4:10:38 PM	88	1266.00	XCSE
GENMAB A/S	14-Apr-2025	4:11:19 PM	36	1266.00	CEUX
GENMAB A/S	14-Apr-2025	4:11:19 PM	36	1266.00	CEUX
GENMAB A/S	14-Apr-2025	4:11:19 PM	79	1265.50	CEUX
GENMAB A/S	14-Apr-2025	4:11:19 PM	9	1265.50	CEUX
GENMAB A/S	14-Apr-2025	4:11:48 PM	100	1265.50	XCSE
GENMAB A/S	14-Apr-2025	4:11:48 PM	6	1265.50	CEUX
GENMAB A/S	14-Apr-2025	4:11:49 PM	100	1265.50	XCSE
GENMAB A/S	14-Apr-2025	4:11:56 PM	78	1265.00	XCSE
GENMAB A/S	14-Apr-2025	4:12:16 PM	31	1266.00	XCSE
GENMAB A/S	14-Apr-2025	4:12:16 PM	23	1266.00	TQEX
GENMAB A/S	14-Apr-2025	4:12:16 PM	3	1266.00	TQEX
GENMAB A/S	14-Apr-2025	4:12:16 PM	20	1266.00	CEUX
GENMAB A/S	14-Apr-2025	4:12:22 PM	51	1266.00	XCSE
GENMAB A/S	14-Apr-2025	4:12:23 PM	6	1266.00	CEUX
GENMAB A/S	14-Apr-2025	4:12:23 PM	6	1266.00	CEUX
GENMAB A/S	14-Apr-2025	4:12:23 PM	6	1266.00	CEUX
GENMAB A/S	14-Apr-2025	4:12:47 PM	89	1266.00	XCSE
GENMAB A/S	14-Apr-2025	4:12:47 PM	35	1266.00	XCSE
GENMAB A/S	14-Apr-2025	4:12:47 PM	40	1266.00	XCSE
GENMAB A/S	14-Apr-2025	4:12:47 PM	25	1266.00	XCSE
GENMAB A/S	14-Apr-2025	4:12:47 PM	11	1266.00	XCSE
GENMAB A/S	14-Apr-2025	4:12:47 PM	1	1266.00	XCSE
GENMAB A/S	14-Apr-2025	4:12:47 PM	12	1266.00	XCSE
GENMAB A/S	14-Apr-2025	4:12:47 PM	11	1266.00	XCSE
GENMAB A/S	14-Apr-2025	4:12:47 PM	40	1266.00	XCSE

Exhibit 99.1(a)

APPENDIX Share buy-back programme - Specification for April 14 – April 18, 2025

GENMAB A/S	14-Apr-2025	4:12:47 PM	11	1266.00	XCSE
GENMAB A/S	14-Apr-2025	4:12:47 PM	27	1266.00	TQEX
GENMAB A/S	14-Apr-2025	4:12:47 PM	22	1266.00	TQEX
GENMAB A/S	14-Apr-2025	4:12:47 PM	27	1266.00	AQEU
GENMAB A/S	14-Apr-2025	4:12:47 PM	36	1266.00	CEUX
GENMAB A/S	14-Apr-2025	4:12:47 PM	45	1265.50	CEUX
GENMAB A/S	14-Apr-2025	4:12:50 PM	39	1265.50	CEUX
GENMAB A/S	14-Apr-2025	4:12:56 PM	4	1265.50	XCSE
GENMAB A/S	14-Apr-2025	4:12:56 PM	82	1265.00	XCSE
GENMAB A/S	14-Apr-2025	4:13:11 PM	36	1266.00	CEUX
GENMAB A/S	14-Apr-2025	4:13:12 PM	13	1266.00	CEUX
GENMAB A/S	14-Apr-2025	4:13:17 PM	32	1266.00	CEUX
GENMAB A/S	14-Apr-2025	4:13:25 PM	48	1267.00	XCSE
GENMAB A/S	14-Apr-2025	4:13:25 PM	64	1267.00	XCSE
GENMAB A/S	14-Apr-2025	4:13:37 PM	2	1267.00	CEUX
GENMAB A/S	14-Apr-2025	4:13:37 PM	23	1267.00	CEUX
GENMAB A/S	14-Apr-2025	4:14:12 PM	23	1267.00	XCSE
GENMAB A/S	14-Apr-2025	4:14:12 PM	64	1267.00	XCSE
GENMAB A/S	14-Apr-2025	4:14:12 PM	40	1267.00	XCSE
GENMAB A/S	14-Apr-2025	4:14:12 PM	5	1267.00	XCSE
GENMAB A/S	14-Apr-2025	4:14:12 PM	11	1267.00	XCSE
GENMAB A/S	14-Apr-2025	4:14:12 PM	39	1267.00	AQEU
GENMAB A/S	14-Apr-2025	4:14:12 PM	88	1266.50	CEUX
GENMAB A/S	14-Apr-2025	4:14:14 PM	68	1266.50	XCSE
GENMAB A/S	14-Apr-2025	4:14:29 PM	82	1266.50	XCSE
GENMAB A/S	14-Apr-2025	4:14:29 PM	24	1266.50	TQEX
GENMAB A/S	14-Apr-2025	4:14:29 PM	8	1266.50	TQEX
GENMAB A/S	14-Apr-2025	4:14:29 PM	25	1266.50	CEUX
GENMAB A/S	14-Apr-2025	4:14:29 PM	32	1266.50	CEUX
GENMAB A/S	14-Apr-2025	4:14:54 PM	56	1266.50	XCSE
GENMAB A/S	14-Apr-2025	4:14:56 PM	4	1266.50	XCSE
GENMAB A/S	14-Apr-2025	4:14:56 PM	23	1266.50	XCSE
GENMAB A/S	14-Apr-2025	4:14:56 PM	10	1266.50	CEUX
GENMAB A/S	14-Apr-2025	4:14:56 PM	70	1266.50	CEUX
GENMAB A/S	14-Apr-2025	4:14:56 PM	5	1266.50	CEUX
GENMAB A/S	14-Apr-2025	4:15:04 PM	65	1266.50	CEUX
GENMAB A/S	14-Apr-2025	4:15:04 PM	23	1266.50	CEUX
GENMAB A/S	14-Apr-2025	4:15:17 PM	30	1266.50	XCSE
GENMAB A/S	14-Apr-2025	4:15:18 PM	58	1266.50	XCSE
GENMAB A/S	14-Apr-2025	4:15:18 PM	62	1266.50	CEUX
GENMAB A/S	14-Apr-2025	4:15:32 PM	31	1266.00	XCSE
GENMAB A/S	14-Apr-2025	4:15:32 PM	57	1265.50	XCSE
GENMAB A/S	14-Apr-2025	4:15:32 PM	29	1265.50	XCSE

Exhibit 99.1(a)

APPENDIX Share buy-back programme - Specification for April 14 – April 18, 2025

GENMAB A/S	14-Apr-2025	4:15:32 PM	25	1266.00	AQEU
GENMAB A/S	14-Apr-2025	4:15:44 PM	10	1265.00	AQEU
GENMAB A/S	14-Apr-2025	4:15:44 PM	89	1265.50	CEUX
GENMAB A/S	14-Apr-2025	4:15:49 PM	58	1265.50	CEUX
GENMAB A/S	14-Apr-2025	4:15:51 PM	6	1265.50	CEUX
GENMAB A/S	14-Apr-2025	4:16:03 PM	31	1265.50	XCSE
GENMAB A/S	14-Apr-2025	4:16:03 PM	51	1265.50	XCSE
GENMAB A/S	14-Apr-2025	4:16:03 PM	43	1265.50	CEUX
GENMAB A/S	14-Apr-2025	4:16:12 PM	4	1265.50	CEUX
GENMAB A/S	14-Apr-2025	4:16:22 PM	21	1265.50	CEUX
GENMAB A/S	14-Apr-2025	4:16:22 PM	6	1265.50	CEUX
GENMAB A/S	14-Apr-2025	4:16:23 PM	30	1265.00	TQEX
GENMAB A/S	14-Apr-2025	4:16:29 PM	40	1265.00	XCSE
GENMAB A/S	14-Apr-2025	4:16:29 PM	12	1265.00	XCSE
GENMAB A/S	14-Apr-2025	4:16:29 PM	10	1265.00	XCSE
GENMAB A/S	14-Apr-2025	4:16:29 PM	20	1265.00	XCSE
GENMAB A/S	14-Apr-2025	4:16:29 PM	11	1265.00	XCSE
GENMAB A/S	14-Apr-2025	4:16:29 PM	28	1265.00	AQEU
GENMAB A/S	14-Apr-2025	4:16:34 PM	89	1264.00	XCSE
GENMAB A/S	14-Apr-2025	4:16:34 PM	8	1264.00	TQEX
GENMAB A/S	14-Apr-2025	4:16:34 PM	25	1264.00	TQEX
GENMAB A/S	14-Apr-2025	4:16:34 PM	17	1264.00	AQEU
GENMAB A/S	14-Apr-2025	4:16:34 PM	88	1264.50	CEUX
GENMAB A/S	14-Apr-2025	4:16:51 PM	84	1264.00	XCSE
GENMAB A/S	14-Apr-2025	4:17:14 PM	29	1264.00	AQEU
GENMAB A/S	14-Apr-2025	4:17:14 PM	39	1263.50	CEUX
GENMAB A/S	14-Apr-2025	4:17:20 PM	12	1264.50	XCSE
GENMAB A/S	14-Apr-2025	4:17:20 PM	12	1264.50	XCSE
GENMAB A/S	14-Apr-2025	4:17:20 PM	13	1264.50	XCSE
GENMAB A/S	14-Apr-2025	4:17:20 PM	20	1264.50	XCSE
GENMAB A/S	14-Apr-2025	4:17:20 PM	30	1264.50	XCSE
GENMAB A/S	14-Apr-2025	4:17:23 PM	83	1264.00	XCSE
GENMAB A/S	14-Apr-2025	4:17:23 PM	2	1263.50	CEUX
GENMAB A/S	14-Apr-2025	4:17:23 PM	3	1263.50	CEUX
GENMAB A/S	14-Apr-2025	4:18:04 PM	43	1263.50	CEUX
GENMAB A/S	14-Apr-2025	4:18:14 PM	89	1263.00	XCSE
GENMAB A/S	14-Apr-2025	4:18:27 PM	40	1264.50	XCSE
GENMAB A/S	14-Apr-2025	4:18:27 PM	25	1264.50	XCSE
GENMAB A/S	14-Apr-2025	4:18:54 PM	35	1264.50	XCSE
GENMAB A/S	14-Apr-2025	4:18:54 PM	23	1264.50	XCSE
GENMAB A/S	14-Apr-2025	4:18:54 PM	40	1264.50	XCSE
GENMAB A/S	14-Apr-2025	4:18:54 PM	12	1264.50	XCSE
GENMAB A/S	14-Apr-2025	4:18:54 PM	26	1264.00	TQEX

Exhibit 99.1(a)

APPENDIX Share buy-back programme - Specification for April 14 – April 18, 2025

GENMAB A/S	14-Apr-2025	4:18:54 PM	20	1264.00	TQEX
GENMAB A/S	14-Apr-2025	4:18:54 PM	33	1264.50	AQEU
GENMAB A/S	14-Apr-2025	4:18:59 PM	20	1263.00	CEUX
GENMAB A/S	14-Apr-2025	4:18:59 PM	5	1263.00	CEUX
GENMAB A/S	14-Apr-2025	4:18:59 PM	9	1263.00	CEUX
GENMAB A/S	14-Apr-2025	4:18:59 PM	3	1263.00	CEUX
GENMAB A/S	14-Apr-2025	4:18:59 PM	24	1263.00	CEUX
GENMAB A/S	14-Apr-2025	4:19:00 PM	41	1263.50	XCSE
GENMAB A/S	14-Apr-2025	4:19:24 PM	83	1263.00	XCSE
GENMAB A/S	14-Apr-2025	4:19:44 PM	87	1264.00	XCSE
GENMAB A/S	14-Apr-2025	4:20:08 PM	32	1265.50	CEUX
GENMAB A/S	14-Apr-2025	4:20:27 PM	12	1265.50	CEUX
GENMAB A/S	14-Apr-2025	4:20:53 PM	86	1264.50	XCSE
GENMAB A/S	14-Apr-2025	4:20:53 PM	52	1265.00	CEUX
GENMAB A/S	14-Apr-2025	4:20:53 PM	34	1265.00	CEUX
GENMAB A/S	14-Apr-2025	4:21:06 PM	29	1264.50	AQEU
GENMAB A/S	14-Apr-2025	4:21:10 PM	7	1264.50	XCSE
GENMAB A/S	14-Apr-2025	4:21:10 PM	33	1264.50	XCSE
GENMAB A/S	14-Apr-2025	4:21:10 PM	11	1264.50	XCSE
GENMAB A/S	14-Apr-2025	4:21:10 PM	13	1264.50	XCSE
GENMAB A/S	14-Apr-2025	4:21:10 PM	10	1264.50	XCSE
GENMAB A/S	14-Apr-2025	4:21:10 PM	13	1264.50	XCSE
GENMAB A/S	14-Apr-2025	4:21:10 PM	32	1264.50	CEUX
GENMAB A/S	14-Apr-2025	4:21:14 PM	35	1264.50	XCSE
GENMAB A/S	14-Apr-2025	4:21:14 PM	28	1264.50	XCSE
GENMAB A/S	14-Apr-2025	4:21:14 PM	40	1264.50	XCSE
GENMAB A/S	14-Apr-2025	4:21:14 PM	9	1264.50	XCSE
GENMAB A/S	14-Apr-2025	4:21:14 PM	39	1264.00	XCSE
GENMAB A/S	14-Apr-2025	4:21:14 PM	50	1264.00	XCSE
GENMAB A/S	14-Apr-2025	4:21:14 PM	34	1264.00	TQEX
GENMAB A/S	14-Apr-2025	4:21:14 PM	5	1264.00	TQEX
GENMAB A/S	14-Apr-2025	4:21:14 PM	87	1264.00	CEUX
GENMAB A/S	14-Apr-2025	4:21:34 PM	63	1264.00	CEUX
GENMAB A/S	14-Apr-2025	4:21:42 PM	85	1264.50	XCSE
GENMAB A/S	14-Apr-2025	4:21:47 PM	83	1264.50	XCSE
GENMAB A/S	14-Apr-2025	4:21:54 PM	86	1264.00	XCSE
GENMAB A/S	14-Apr-2025	4:22:04 PM	55	1264.50	XCSE
GENMAB A/S	14-Apr-2025	4:22:35 PM	25	1264.50	AQEU
GENMAB A/S	14-Apr-2025	4:22:43 PM	31	1264.50	XCSE
GENMAB A/S	14-Apr-2025	4:22:43 PM	32	1264.50	CEUX
GENMAB A/S	14-Apr-2025	4:22:50 PM	14	1264.50	XCSE
GENMAB A/S	14-Apr-2025	4:22:50 PM	12	1264.50	XCSE
GENMAB A/S	14-Apr-2025	4:22:50 PM	10	1264.50	XCSE

Exhibit 99.1(a)

APPENDIX Share buy-back programme - Specification for April 14 – April 18, 2025

GENMAB A/S	14-Apr-2025	4:22:50 PM	40	1264.50	XCSE
GENMAB A/S	14-Apr-2025	4:22:50 PM	25	1264.50	XCSE
GENMAB A/S	14-Apr-2025	4:22:50 PM	25	1264.00	XCSE
GENMAB A/S	14-Apr-2025	4:22:50 PM	43	1264.00	CEUX
GENMAB A/S	14-Apr-2025	4:22:51 PM	37	1263.50	TQEX
GENMAB A/S	14-Apr-2025	4:23:24 PM	48	1264.00	XCSE
GENMAB A/S	14-Apr-2025	4:23:24 PM	40	1264.00	XCSE
GENMAB A/S	14-Apr-2025	4:23:24 PM	18	1264.00	XCSE
GENMAB A/S	14-Apr-2025	4:23:24 PM	1	1264.00	XCSE
GENMAB A/S	14-Apr-2025	4:23:24 PM	27	1264.00	CEUX
GENMAB A/S	14-Apr-2025	4:23:34 PM	64	1264.00	XCSE
GENMAB A/S	14-Apr-2025	4:23:34 PM	66	1264.00	CEUX
GENMAB A/S	14-Apr-2025	4:23:34 PM	21	1264.00	CEUX
GENMAB A/S	14-Apr-2025	4:23:44 PM	22	1264.00	XCSE
GENMAB A/S	14-Apr-2025	4:23:59 PM	59	1263.00	XCSE
GENMAB A/S	14-Apr-2025	4:24:02 PM	2	1263.50	AQEU
GENMAB A/S	14-Apr-2025	4:24:03 PM	2	1263.50	AQEU
GENMAB A/S	14-Apr-2025	4:24:03 PM	2	1263.50	AQEU
GENMAB A/S	14-Apr-2025	4:24:04 PM	26	1263.00	XCSE
GENMAB A/S	14-Apr-2025	4:24:04 PM	19	1263.50	AQEU
GENMAB A/S	14-Apr-2025	4:24:04 PM	30	1263.00	CEUX
GENMAB A/S	14-Apr-2025	4:24:04 PM	54	1263.00	CEUX
GENMAB A/S	14-Apr-2025	4:24:34 PM	89	1264.00	XCSE
GENMAB A/S	14-Apr-2025	4:24:34 PM	39	1264.00	CEUX
GENMAB A/S	14-Apr-2025	4:24:34 PM	45	1264.00	CEUX
GENMAB A/S	14-Apr-2025	4:25:04 PM	72	1263.00	XCSE
GENMAB A/S	14-Apr-2025	4:25:04 PM	38	1263.50	AQEU
GENMAB A/S	14-Apr-2025	4:25:24 PM	89	1264.50	XCSE
GENMAB A/S	14-Apr-2025	4:25:27 PM	15	1264.50	CEUX
GENMAB A/S	14-Apr-2025	4:25:39 PM	17	1265.00	CEUX
GENMAB A/S	14-Apr-2025	4:25:54 PM	71	1265.00	CEUX
GENMAB A/S	14-Apr-2025	4:26:31 PM	60	1266.00	XCSE
GENMAB A/S	14-Apr-2025	4:26:31 PM	27	1266.00	XCSE
GENMAB A/S	14-Apr-2025	4:26:38 PM	86	1266.50	XCSE
GENMAB A/S	14-Apr-2025	4:26:38 PM	2	1266.50	XCSE
GENMAB A/S	14-Apr-2025	4:26:54 PM	86	1266.00	XCSE
GENMAB A/S	14-Apr-2025	4:26:54 PM	25	1266.50	TQEX
GENMAB A/S	14-Apr-2025	4:26:56 PM	1	1266.50	TQEX
GENMAB A/S	14-Apr-2025	4:27:08 PM	13	1267.00	XCSE
GENMAB A/S	14-Apr-2025	4:27:08 PM	40	1267.00	XCSE
GENMAB A/S	14-Apr-2025	4:27:08 PM	12	1267.00	XCSE
GENMAB A/S	14-Apr-2025	4:27:08 PM	13	1267.00	XCSE
GENMAB A/S	14-Apr-2025	4:27:08 PM	13	1267.00	XCSE

Exhibit 99.1(a)

APPENDIX Share buy-back programme - Specification for April 14 – April 18, 2025

GENMAB A/S	14-Apr-2025	4:27:08 PM	85	1266.50	XCSE
GENMAB A/S	14-Apr-2025	4:27:08 PM	36	1267.00	CEUX
GENMAB A/S	14-Apr-2025	4:27:08 PM	5	1267.00	CEUX
GENMAB A/S	14-Apr-2025	4:27:08 PM	5	1267.00	CEUX
GENMAB A/S	14-Apr-2025	4:27:08 PM	6	1267.00	CEUX
GENMAB A/S	14-Apr-2025	4:27:08 PM	3	1267.00	CEUX
GENMAB A/S	14-Apr-2025	4:27:08 PM	20	1267.00	CEUX
GENMAB A/S	14-Apr-2025	4:27:09 PM	49	1267.00	CEUX
GENMAB A/S	14-Apr-2025	4:27:19 PM	32	1267.00	CEUX
GENMAB A/S	14-Apr-2025	4:27:24 PM	82	1267.00	XCSE
GENMAB A/S	14-Apr-2025	4:27:25 PM	38	1267.00	AQEU
GENMAB A/S	14-Apr-2025	4:27:25 PM	32	1267.00	CEUX
GENMAB A/S	14-Apr-2025	4:27:37 PM	90	1267.00	XCSE
GENMAB A/S	14-Apr-2025	4:27:39 PM	30	1266.50	TQEX
GENMAB A/S	14-Apr-2025	4:27:39 PM	25	1266.50	CEUX
GENMAB A/S	14-Apr-2025	4:27:54 PM	11	1267.00	XCSE
GENMAB A/S	14-Apr-2025	4:27:54 PM	12	1267.00	XCSE
GENMAB A/S	14-Apr-2025	4:27:54 PM	2	1267.00	XCSE
GENMAB A/S	14-Apr-2025	4:28:24 PM	25	1266.50	TQEX
GENMAB A/S	14-Apr-2025	4:28:27 PM	49	1267.00	CEUX
GENMAB A/S	14-Apr-2025	4:28:27 PM	14	1267.00	CEUX
GENMAB A/S	14-Apr-2025	4:28:34 PM	12	1267.00	CEUX
GENMAB A/S	14-Apr-2025	4:28:48 PM	82	1267.00	XCSE
GENMAB A/S	14-Apr-2025	4:28:49 PM	36	1267.50	CEUX
GENMAB A/S	14-Apr-2025	4:28:53 PM	100	1267.50	XCSE
GENMAB A/S	14-Apr-2025	4:28:53 PM	12	1267.50	XCSE
GENMAB A/S	14-Apr-2025	4:28:53 PM	32	1267.50	CEUX
GENMAB A/S	14-Apr-2025	4:29:07 PM	35	1267.50	XCSE
GENMAB A/S	14-Apr-2025	4:29:07 PM	39	1267.50	TQEX
GENMAB A/S	14-Apr-2025	4:29:07 PM	25	1267.50	AQEU
GENMAB A/S	14-Apr-2025	4:29:09 PM	35	1267.50	XCSE
GENMAB A/S	14-Apr-2025	4:29:09 PM	11	1267.50	XCSE
GENMAB A/S	14-Apr-2025	4:29:09 PM	40	1267.50	XCSE
GENMAB A/S	14-Apr-2025	4:29:09 PM	85	1267.00	XCSE
GENMAB A/S	14-Apr-2025	4:29:09 PM	32	1267.50	CEUX
GENMAB A/S	14-Apr-2025	4:29:09 PM	48	1267.00	CEUX
GENMAB A/S	14-Apr-2025	4:29:09 PM	37	1267.00	CEUX
GENMAB A/S	14-Apr-2025	4:29:34 PM	85	1266.00	XCSE
GENMAB A/S	14-Apr-2025	4:29:54 PM	74	1266.50	XCSE
GENMAB A/S	14-Apr-2025	4:30:05 PM	36	1267.00	CEUX
GENMAB A/S	14-Apr-2025	4:30:24 PM	85	1266.00	XCSE
GENMAB A/S	14-Apr-2025	4:30:27 PM	19	1266.50	CEUX
GENMAB A/S	14-Apr-2025	4:30:28 PM	12	1266.50	CEUX

Exhibit 99.1(a)

APPENDIX Share buy-back programme - Specification for April 14 – April 18, 2025

GENMAB A/S	14-Apr-2025	4:30:30 PM	3	1266.50	CEUX
GENMAB A/S	14-Apr-2025	4:30:35 PM	70	1266.50	XCSE
GENMAB A/S	14-Apr-2025	4:30:42 PM	61	1266.50	XCSE
GENMAB A/S	14-Apr-2025	4:30:43 PM	16	1266.50	XCSE
GENMAB A/S	14-Apr-2025	4:30:43 PM	86	1265.00	XCSE
GENMAB A/S	14-Apr-2025	4:30:43 PM	9	1265.00	XCSE
GENMAB A/S	14-Apr-2025	4:30:43 PM	23	1265.00	XCSE
GENMAB A/S	14-Apr-2025	4:30:43 PM	27	1266.00	AQEU
GENMAB A/S	14-Apr-2025	4:30:43 PM	87	1266.00	CEUX
GENMAB A/S	14-Apr-2025	4:30:43 PM	84	1265.00	CEUX
GENMAB A/S	14-Apr-2025	4:30:50 PM	34	1265.00	XCSE
GENMAB A/S	14-Apr-2025	4:30:50 PM	23	1265.00	CEUX
GENMAB A/S	14-Apr-2025	4:30:50 PM	11	1265.00	CEUX
GENMAB A/S	14-Apr-2025	4:31:04 PM	18	1264.00	XCSE
GENMAB A/S	14-Apr-2025	4:31:04 PM	31	1264.50	CEUX
GENMAB A/S	14-Apr-2025	4:31:04 PM	9	1264.50	CEUX
GENMAB A/S	14-Apr-2025	4:31:14 PM	13	1264.00	XCSE
GENMAB A/S	14-Apr-2025	4:31:47 PM	63	1264.50	XCSE
GENMAB A/S	14-Apr-2025	4:32:13 PM	35	1265.50	XCSE
GENMAB A/S	14-Apr-2025	4:32:13 PM	13	1265.50	XCSE
GENMAB A/S	14-Apr-2025	4:32:13 PM	30	1265.50	XCSE
GENMAB A/S	14-Apr-2025	4:32:13 PM	81	1265.00	XCSE
GENMAB A/S	14-Apr-2025	4:32:21 PM	47	1265.00	XCSE
GENMAB A/S	14-Apr-2025	4:32:21 PM	2	1265.00	XCSE
GENMAB A/S	14-Apr-2025	4:32:21 PM	6	1265.00	XCSE
GENMAB A/S	14-Apr-2025	4:32:27 PM	36	1265.50	CEUX
GENMAB A/S	14-Apr-2025	4:32:27 PM	5	1265.50	CEUX
GENMAB A/S	14-Apr-2025	4:32:27 PM	5	1265.50	CEUX
GENMAB A/S	14-Apr-2025	4:32:27 PM	5	1265.50	CEUX
GENMAB A/S	14-Apr-2025	4:32:34 PM	25	1264.50	TQEX
GENMAB A/S	14-Apr-2025	4:32:34 PM	63	1264.50	CEUX
GENMAB A/S	14-Apr-2025	4:32:35 PM	3	1264.50	AQEU
GENMAB A/S	14-Apr-2025	4:32:46 PM	71	1263.50	XCSE
GENMAB A/S	14-Apr-2025	4:32:51 PM	3	1264.50	AQEU
GENMAB A/S	14-Apr-2025	4:33:04 PM	20	1264.50	AQEU
GENMAB A/S	14-Apr-2025	4:33:05 PM	13	1264.50	AQEU
GENMAB A/S	14-Apr-2025	4:33:08 PM	15	1264.00	CEUX
GENMAB A/S	14-Apr-2025	4:33:12 PM	50	1264.50	XCSE
GENMAB A/S	14-Apr-2025	4:33:41 PM	10	1264.50	XCSE
GENMAB A/S	14-Apr-2025	4:33:41 PM	25	1264.50	XCSE
GENMAB A/S	14-Apr-2025	4:33:41 PM	51	1264.50	XCSE
GENMAB A/S	14-Apr-2025	4:33:41 PM	10	1264.50	XCSE
GENMAB A/S	14-Apr-2025	4:33:41 PM	6	1264.50	XCSE

Exhibit 99.1(a)

APPENDIX Share buy-back programme - Specification for April 14 – April 18, 2025

GENMAB A/S	14-Apr-2025	4:33:41 PM	10	1264.50	XCSE
GENMAB A/S	14-Apr-2025	4:33:41 PM	36	1264.50	CEUX
GENMAB A/S	14-Apr-2025	4:33:41 PM	5	1264.50	CEUX
GENMAB A/S	14-Apr-2025	4:33:41 PM	5	1264.50	CEUX
GENMAB A/S	14-Apr-2025	4:33:41 PM	6	1264.50	CEUX
GENMAB A/S	14-Apr-2025	4:33:41 PM	3	1264.50	CEUX
GENMAB A/S	14-Apr-2025	4:33:41 PM	20	1264.50	CEUX
GENMAB A/S	14-Apr-2025	4:33:41 PM	5	1264.50	CEUX
GENMAB A/S	14-Apr-2025	4:33:41 PM	18	1264.50	CEUX
GENMAB A/S	14-Apr-2025	4:33:50 PM	69	1264.50	XCSE
GENMAB A/S	14-Apr-2025	4:33:50 PM	8	1264.50	XCSE
GENMAB A/S	14-Apr-2025	4:33:50 PM	81	1263.50	XCSE
GENMAB A/S	14-Apr-2025	4:33:53 PM	9	1264.00	AQEU
GENMAB A/S	14-Apr-2025	4:33:53 PM	33	1264.00	AQEU
GENMAB A/S	14-Apr-2025	4:33:58 PM	32	1264.00	CEUX
GENMAB A/S	14-Apr-2025	4:34:02 PM	1	1263.50	XCSE
GENMAB A/S	14-Apr-2025	4:34:02 PM	34	1263.50	TQEX
GENMAB A/S	14-Apr-2025	4:34:02 PM	39	1263.50	CEUX
GENMAB A/S	14-Apr-2025	4:34:26 PM	27	1262.50	XCSE
GENMAB A/S	14-Apr-2025	4:34:26 PM	5	1263.00	CEUX
GENMAB A/S	14-Apr-2025	4:34:26 PM	6	1263.00	CEUX
GENMAB A/S	14-Apr-2025	4:34:26 PM	6	1263.00	CEUX
GENMAB A/S	14-Apr-2025	4:34:26 PM	8	1263.00	CEUX
GENMAB A/S	14-Apr-2025	4:34:30 PM	35	1263.00	XCSE
GENMAB A/S	14-Apr-2025	4:34:30 PM	10	1263.00	XCSE
GENMAB A/S	14-Apr-2025	4:34:30 PM	36	1263.00	XCSE
GENMAB A/S	14-Apr-2025	4:34:40 PM	32	1263.00	CEUX
GENMAB A/S	14-Apr-2025	4:34:40 PM	28	1262.50	CEUX
GENMAB A/S	14-Apr-2025	4:34:40 PM	8	1262.50	CEUX
GENMAB A/S	14-Apr-2025	4:34:52 PM	66	1262.50	XCSE
GENMAB A/S	14-Apr-2025	4:35:05 PM	31	1263.00	XCSE
GENMAB A/S	14-Apr-2025	4:35:07 PM	14	1263.00	CEUX
GENMAB A/S	14-Apr-2025	4:35:52 PM	11	1265.50	XCSE
GENMAB A/S	14-Apr-2025	4:35:52 PM	51	1265.50	XCSE
GENMAB A/S	14-Apr-2025	4:35:52 PM	13	1265.50	XCSE
GENMAB A/S	14-Apr-2025	4:35:52 PM	12	1265.50	XCSE
GENMAB A/S	14-Apr-2025	4:35:52 PM	25	1265.00	TQEX
GENMAB A/S	14-Apr-2025	4:35:54 PM	18	1265.00	TQEX
GENMAB A/S	14-Apr-2025	4:35:59 PM	36	1265.50	CEUX
GENMAB A/S	14-Apr-2025	4:36:00 PM	36	1265.50	CEUX
GENMAB A/S	14-Apr-2025	4:36:01 PM	35	1265.50	XCSE
GENMAB A/S	14-Apr-2025	4:36:01 PM	29	1265.50	XCSE
GENMAB A/S	14-Apr-2025	4:36:01 PM	35	1265.50	XCSE

Exhibit 99.1(a)

APPENDIX Share buy-back programme - Specification for April 14 – April 18, 2025

GENMAB A/S	14-Apr-2025	4:36:01 PM	12	1265.50	XCSE
GENMAB A/S	14-Apr-2025	4:36:01 PM	13	1265.50	CEUX
GENMAB A/S	14-Apr-2025	4:36:24 PM	88	1265.50	XCSE
GENMAB A/S	14-Apr-2025	4:36:24 PM	87	1265.50	CEUX
GENMAB A/S	14-Apr-2025	4:36:40 PM	28	1265.50	AQEU
GENMAB A/S	14-Apr-2025	4:36:44 PM	5	1265.50	CEUX
GENMAB A/S	14-Apr-2025	4:36:44 PM	36	1265.50	CEUX
GENMAB A/S	14-Apr-2025	4:36:44 PM	21	1265.50	CEUX
GENMAB A/S	14-Apr-2025	4:36:50 PM	10	1265.50	XCSE
GENMAB A/S	14-Apr-2025	4:36:50 PM	11	1265.50	XCSE
GENMAB A/S	14-Apr-2025	4:36:50 PM	51	1265.50	XCSE
GENMAB A/S	14-Apr-2025	4:36:50 PM	13	1265.50	XCSE
GENMAB A/S	14-Apr-2025	4:36:50 PM	12	1265.50	XCSE
GENMAB A/S	14-Apr-2025	4:36:50 PM	10	1265.00	TQEX
GENMAB A/S	14-Apr-2025	4:36:50 PM	20	1265.00	CEUX
GENMAB A/S	14-Apr-2025	4:37:04 PM	13	1265.50	XCSE
GENMAB A/S	14-Apr-2025	4:37:04 PM	51	1265.50	XCSE
GENMAB A/S	14-Apr-2025	4:37:04 PM	13	1265.50	XCSE
GENMAB A/S	14-Apr-2025	4:37:04 PM	15	1265.50	XCSE
GENMAB A/S	14-Apr-2025	4:37:04 PM	32	1265.50	CEUX
GENMAB A/S	14-Apr-2025	4:37:05 PM	35	1265.50	XCSE
GENMAB A/S	14-Apr-2025	4:37:05 PM	31	1265.50	XCSE
GENMAB A/S	14-Apr-2025	4:37:05 PM	31	1265.50	XCSE
GENMAB A/S	14-Apr-2025	4:37:34 PM	82	1265.50	XCSE
GENMAB A/S	14-Apr-2025	4:37:35 PM	13	1265.50	XCSE
GENMAB A/S	14-Apr-2025	4:37:35 PM	13	1265.50	XCSE
GENMAB A/S	14-Apr-2025	4:37:35 PM	11	1265.50	XCSE
GENMAB A/S	14-Apr-2025	4:37:35 PM	15	1265.50	XCSE
GENMAB A/S	14-Apr-2025	4:37:35 PM	40	1265.50	CEUX
GENMAB A/S	14-Apr-2025	4:37:37 PM	42	1265.50	CEUX
GENMAB A/S	14-Apr-2025	4:38:03 PM	4	1267.00	CEUX
GENMAB A/S	14-Apr-2025	4:38:04 PM	28	1266.50	TQEX
GENMAB A/S	14-Apr-2025	4:38:04 PM	82	1266.50	CEUX
GENMAB A/S	14-Apr-2025	4:38:28 PM	30	1267.00	CEUX
GENMAB A/S	14-Apr-2025	4:38:40 PM	83	1267.00	XCSE
GENMAB A/S	14-Apr-2025	4:38:40 PM	4	1266.50	TQEX
GENMAB A/S	14-Apr-2025	4:38:40 PM	2	1266.50	TQEX
GENMAB A/S	14-Apr-2025	4:38:40 PM	2	1266.50	TQEX
GENMAB A/S	14-Apr-2025	4:38:40 PM	2	1266.50	TQEX
GENMAB A/S	14-Apr-2025	4:38:40 PM	3	1266.50	TQEX
GENMAB A/S	14-Apr-2025	4:38:40 PM	3	1266.50	TQEX
GENMAB A/S	14-Apr-2025	4:38:40 PM	5	1266.50	TQEX
GENMAB A/S	14-Apr-2025	4:38:40 PM	5	1266.50	TQEX

Exhibit 99.1(a)

APPENDIX Share buy-back programme - Specification for April 14 – April 18, 2025

GENMAB A/S	14-Apr-2025	4:38:40 PM	5	1266.50	TQEX
GENMAB A/S	14-Apr-2025	4:38:40 PM	5	1266.50	TQEX
GENMAB A/S	14-Apr-2025	4:38:40 PM	36	1267.00	CEUX
GENMAB A/S	14-Apr-2025	4:38:40 PM	3	1266.50	CEUX
GENMAB A/S	14-Apr-2025	4:38:40 PM	4	1266.50	CEUX
GENMAB A/S	14-Apr-2025	4:38:40 PM	37	1267.00	AQEU
GENMAB A/S	14-Apr-2025	4:38:41 PM	47	1267.00	XCSE
GENMAB A/S	14-Apr-2025	4:38:46 PM	33	1267.00	XCSE
GENMAB A/S	14-Apr-2025	4:38:46 PM	51	1267.00	XCSE
GENMAB A/S	14-Apr-2025	4:38:47 PM	47	1267.00	XCSE
GENMAB A/S	14-Apr-2025	4:38:47 PM	36	1267.00	CEUX
GENMAB A/S	14-Apr-2025	4:38:47 PM	6	1267.00	CEUX
GENMAB A/S	14-Apr-2025	4:38:52 PM	11	1267.00	XCSE
GENMAB A/S	14-Apr-2025	4:38:52 PM	32	1267.00	XCSE
GENMAB A/S	14-Apr-2025	4:38:52 PM	12	1267.00	XCSE
GENMAB A/S	14-Apr-2025	4:38:52 PM	12	1267.00	XCSE
GENMAB A/S	14-Apr-2025	4:38:52 PM	11	1267.00	XCSE
GENMAB A/S	14-Apr-2025	4:38:52 PM	14	1267.00	XCSE
GENMAB A/S	14-Apr-2025	4:39:00 PM	18	1267.00	XCSE
GENMAB A/S	14-Apr-2025	4:39:00 PM	12	1267.00	XCSE
GENMAB A/S	14-Apr-2025	4:39:00 PM	11	1267.00	XCSE
GENMAB A/S	14-Apr-2025	4:39:00 PM	12	1267.00	XCSE
GENMAB A/S	14-Apr-2025	4:39:00 PM	35	1267.00	XCSE
GENMAB A/S	14-Apr-2025	4:39:00 PM	55	1266.50	CEUX
GENMAB A/S	14-Apr-2025	4:39:08 PM	37	1266.50	TQEX
GENMAB A/S	14-Apr-2025	4:39:08 PM	55	1266.50	CEUX
GENMAB A/S	14-Apr-2025	4:39:14 PM	88	1266.00	XCSE
GENMAB A/S	14-Apr-2025	4:39:31 PM	25	1267.00	AQEU
GENMAB A/S	14-Apr-2025	4:39:40 PM	49	1267.50	XCSE
GENMAB A/S	14-Apr-2025	4:39:40 PM	35	1267.50	XCSE
GENMAB A/S	14-Apr-2025	4:39:40 PM	5	1267.50	XCSE
GENMAB A/S	14-Apr-2025	4:39:40 PM	61	1266.50	XCSE
GENMAB A/S	14-Apr-2025	4:39:40 PM	25	1266.50	CEUX
GENMAB A/S	14-Apr-2025	4:39:47 PM	13	1266.50	CEUX
GENMAB A/S	14-Apr-2025	4:40:05 PM	37	1266.50	CEUX
GENMAB A/S	14-Apr-2025	4:40:13 PM	82	1266.50	XCSE
GENMAB A/S	14-Apr-2025	4:40:15 PM	4	1266.50	XCSE
GENMAB A/S	14-Apr-2025	4:40:15 PM	38	1266.50	TQEX
GENMAB A/S	14-Apr-2025	4:40:15 PM	48	1266.50	AQEU
GENMAB A/S	14-Apr-2025	4:40:30 PM	32	1266.50	XCSE
GENMAB A/S	14-Apr-2025	4:40:30 PM	10	1266.50	XCSE
GENMAB A/S	14-Apr-2025	4:40:30 PM	11	1266.50	XCSE
GENMAB A/S	14-Apr-2025	4:40:30 PM	12	1266.50	XCSE

Exhibit 99.1(a)

APPENDIX Share buy-back programme - Specification for April 14 – April 18, 2025

GENMAB A/S	14-Apr-2025	4:40:30 PM	47	1266.50	XCSE
GENMAB A/S	14-Apr-2025	4:40:31 PM	6	1266.50	CEUX
GENMAB A/S	14-Apr-2025	4:40:31 PM	5	1266.50	CEUX
GENMAB A/S	14-Apr-2025	4:40:31 PM	6	1266.50	CEUX
GENMAB A/S	14-Apr-2025	4:40:31 PM	11	1266.50	CEUX
GENMAB A/S	14-Apr-2025	4:40:41 PM	36	1266.50	CEUX
GENMAB A/S	14-Apr-2025	4:40:54 PM	78	1266.50	XCSE
GENMAB A/S	14-Apr-2025	4:40:54 PM	32	1267.00	CEUX
GENMAB A/S	14-Apr-2025	4:40:54 PM	33	1267.00	CEUX
GENMAB A/S	14-Apr-2025	4:41:31 PM	70	1267.50	XCSE
GENMAB A/S	14-Apr-2025	4:41:31 PM	13	1267.50	XCSE
GENMAB A/S	14-Apr-2025	4:41:31 PM	86	1267.50	XCSE
GENMAB A/S	14-Apr-2025	4:41:31 PM	85	1267.50	XCSE
GENMAB A/S	14-Apr-2025	4:41:31 PM	86	1268.00	CEUX
GENMAB A/S	14-Apr-2025	4:41:38 PM	5	1268.00	CEUX
GENMAB A/S	14-Apr-2025	4:41:56 PM	11	1268.50	XCSE
GENMAB A/S	14-Apr-2025	4:41:56 PM	13	1268.50	XCSE
GENMAB A/S	14-Apr-2025	4:41:56 PM	51	1268.50	XCSE
GENMAB A/S	14-Apr-2025	4:41:58 PM	13	1268.50	XCSE
GENMAB A/S	14-Apr-2025	4:42:14 PM	11	1269.00	CEUX
GENMAB A/S	14-Apr-2025	4:42:14 PM	12	1269.00	CEUX
GENMAB A/S	14-Apr-2025	4:42:15 PM	26	1269.00	CEUX
GENMAB A/S	14-Apr-2025	4:42:15 PM	36	1269.00	CEUX
GENMAB A/S	14-Apr-2025	4:42:15 PM	5	1269.00	CEUX
GENMAB A/S	14-Apr-2025	4:42:15 PM	5	1269.00	CEUX
GENMAB A/S	14-Apr-2025	4:42:15 PM	6	1269.50	CEUX
GENMAB A/S	14-Apr-2025	4:42:15 PM	5	1269.50	CEUX
GENMAB A/S	14-Apr-2025	4:42:15 PM	14	1269.50	CEUX
GENMAB A/S	14-Apr-2025	4:42:16 PM	6	1269.00	CEUX
GENMAB A/S	14-Apr-2025	4:42:16 PM	5	1269.00	CEUX
GENMAB A/S	14-Apr-2025	4:42:17 PM	4	1269.00	CEUX
GENMAB A/S	14-Apr-2025	4:42:17 PM	6	1269.00	CEUX
GENMAB A/S	14-Apr-2025	4:42:19 PM	39	1269.00	CEUX
GENMAB A/S	14-Apr-2025	4:42:20 PM	48	1269.00	XCSE
GENMAB A/S	14-Apr-2025	4:42:25 PM	11	1269.00	XCSE
GENMAB A/S	14-Apr-2025	4:42:25 PM	13	1269.00	XCSE
GENMAB A/S	14-Apr-2025	4:42:25 PM	51	1269.00	XCSE
GENMAB A/S	14-Apr-2025	4:42:25 PM	11	1269.00	XCSE
GENMAB A/S	14-Apr-2025	4:42:29 PM	31	1268.50	XCSE
GENMAB A/S	14-Apr-2025	4:42:29 PM	39	1268.50	AQEU
GENMAB A/S	14-Apr-2025	4:42:40 PM	37	1268.50	XCSE
GENMAB A/S	14-Apr-2025	4:42:45 PM	13	1269.00	XCSE
GENMAB A/S	14-Apr-2025	4:42:45 PM	12	1269.00	XCSE

Exhibit 99.1(a)

APPENDIX Share buy-back programme - Specification for April 14 – April 18, 2025

GENMAB A/S	14-Apr-2025	4:42:45 PM	11	1269.00	XCSE
GENMAB A/S	14-Apr-2025	4:42:45 PM	13	1269.00	XCSE
GENMAB A/S	14-Apr-2025	4:42:45 PM	2	1269.00	XCSE
GENMAB A/S	14-Apr-2025	4:42:45 PM	29	1268.50	XCSE
GENMAB A/S	14-Apr-2025	4:42:45 PM	4	1268.50	TQEX
GENMAB A/S	14-Apr-2025	4:42:45 PM	9	1268.50	TQEX
GENMAB A/S	14-Apr-2025	4:42:45 PM	4	1268.50	TQEX
GENMAB A/S	14-Apr-2025	4:42:45 PM	7	1268.50	TQEX
GENMAB A/S	14-Apr-2025	4:42:54 PM	17	1268.50	XCSE
GENMAB A/S	14-Apr-2025	4:42:57 PM	13	1269.50	XCSE
GENMAB A/S	14-Apr-2025	4:42:57 PM	11	1269.50	XCSE
GENMAB A/S	14-Apr-2025	4:42:57 PM	13	1269.50	XCSE
GENMAB A/S	14-Apr-2025	4:42:57 PM	26	1269.50	CEUX
GENMAB A/S	14-Apr-2025	4:43:00 PM	25	1269.50	TQEX
GENMAB A/S	14-Apr-2025	4:43:00 PM	8	1270.00	CEUX
GENMAB A/S	14-Apr-2025	4:43:02 PM	31	1269.50	XCSE
GENMAB A/S	14-Apr-2025	4:43:14 PM	63	1268.50	XCSE
GENMAB A/S	14-Apr-2025	4:43:14 PM	75	1269.00	CEUX
GENMAB A/S	14-Apr-2025	4:43:14 PM	3	1269.00	CEUX
GENMAB A/S	14-Apr-2025	4:43:14 PM	36	1269.50	CEUX
GENMAB A/S	14-Apr-2025	4:43:14 PM	11	1269.50	CEUX
GENMAB A/S	14-Apr-2025	4:43:14 PM	36	1269.50	CEUX
GENMAB A/S	14-Apr-2025	4:43:16 PM	42	1269.00	CEUX
GENMAB A/S	14-Apr-2025	4:43:18 PM	14	1268.50	XCSE
GENMAB A/S	14-Apr-2025	4:43:48 PM	69	1268.50	XCSE
GENMAB A/S	14-Apr-2025	4:44:04 PM	15	1268.50	XCSE
GENMAB A/S	14-Apr-2025	4:44:21 PM	89	1269.00	XCSE
GENMAB A/S	14-Apr-2025	4:44:21 PM	32	1269.50	CEUX
GENMAB A/S	14-Apr-2025	4:44:22 PM	17	1269.50	CEUX
GENMAB A/S	14-Apr-2025	4:44:22 PM	26	1269.50	CEUX
GENMAB A/S	14-Apr-2025	4:44:26 PM	7	1269.00	TQEX
GENMAB A/S	14-Apr-2025	4:44:26 PM	65	1269.00	CEUX
GENMAB A/S	14-Apr-2025	4:44:27 PM	14	1269.00	TQEX
GENMAB A/S	14-Apr-2025	4:44:42 PM	2	1269.00	TQEX
GENMAB A/S	14-Apr-2025	4:44:44 PM	3	1269.00	TQEX
GENMAB A/S	14-Apr-2025	4:45:03 PM	29	1268.00	CEUX
GENMAB A/S	14-Apr-2025	4:45:03 PM	15	1268.50	AQEU
GENMAB A/S	14-Apr-2025	4:45:11 PM	51	1269.00	XCSE
GENMAB A/S	14-Apr-2025	4:45:11 PM	13	1269.00	XCSE
GENMAB A/S	14-Apr-2025	4:45:11 PM	21	1269.00	XCSE
GENMAB A/S	14-Apr-2025	4:45:11 PM	12	1269.00	XCSE
GENMAB A/S	14-Apr-2025	4:45:11 PM	10	1269.00	XCSE
GENMAB A/S	14-Apr-2025	4:45:11 PM	5	1269.00	XCSE

Exhibit 99.1(a)

APPENDIX Share buy-back programme - Specification for April 14 – April 18, 2025

GENMAB A/S	14-Apr-2025	4:45:11 PM	10	1268.50	AQEU
GENMAB A/S	14-Apr-2025	4:45:12 PM	49	1269.00	XCSE
GENMAB A/S	14-Apr-2025	4:45:12 PM	30	1269.00	XCSE
GENMAB A/S	14-Apr-2025	4:45:12 PM	33	1269.00	XCSE
GENMAB A/S	14-Apr-2025	4:45:12 PM	18	1269.00	XCSE
GENMAB A/S	14-Apr-2025	4:45:12 PM	12	1269.00	XCSE
GENMAB A/S	14-Apr-2025	4:45:12 PM	13	1269.00	XCSE
GENMAB A/S	14-Apr-2025	4:45:12 PM	10	1269.00	XCSE
GENMAB A/S	14-Apr-2025	4:45:12 PM	30	1269.00	XCSE
GENMAB A/S	14-Apr-2025	4:45:12 PM	10	1269.00	XCSE
GENMAB A/S	14-Apr-2025	4:45:12 PM	51	1269.00	XCSE
GENMAB A/S	14-Apr-2025	4:45:12 PM	12	1269.00	XCSE
GENMAB A/S	14-Apr-2025	4:45:12 PM	12	1269.00	XCSE
GENMAB A/S	14-Apr-2025	4:45:12 PM	12	1269.00	XCSE
GENMAB A/S	14-Apr-2025	4:45:12 PM	10	1269.00	XCSE
GENMAB A/S	14-Apr-2025	4:45:12 PM	5	1269.00	XCSE
GENMAB A/S	14-Apr-2025	4:45:28 PM	66	1269.00	XCSE
GENMAB A/S	14-Apr-2025	4:45:43 PM	10	1269.00	XCSE
GENMAB A/S	14-Apr-2025	4:45:43 PM	33	1269.00	CEUX
GENMAB A/S	14-Apr-2025	4:45:54 PM	73	1269.50	XCSE
GENMAB A/S	14-Apr-2025	4:46:03 PM	31	1270.00	TQEX
GENMAB A/S	14-Apr-2025	4:46:03 PM	3	1270.00	TQEX
GENMAB A/S	14-Apr-2025	4:46:14 PM	16	1269.50	XCSE
GENMAB A/S	14-Apr-2025	4:46:23 PM	89	1270.00	XCSE
GENMAB A/S	14-Apr-2025	4:46:23 PM	21	1269.00	CEUX
GENMAB A/S	14-Apr-2025	4:46:34 PM	85	1269.50	XCSE
GENMAB A/S	14-Apr-2025	4:46:35 PM	7	1269.50	AQEU
GENMAB A/S	14-Apr-2025	4:46:42 PM	27	1269.50	AQEU
GENMAB A/S	14-Apr-2025	4:46:51 PM	35	1269.50	CEUX
GENMAB A/S	14-Apr-2025	4:46:54 PM	61	1269.50	CEUX
GENMAB A/S	14-Apr-2025	4:46:54 PM	50	1269.50	CEUX
GENMAB A/S	14-Apr-2025	4:46:54 PM	21	1269.00	CEUX
GENMAB A/S	14-Apr-2025	4:46:57 PM	22	1269.50	XCSE
GENMAB A/S	14-Apr-2025	4:46:58 PM	59	1269.50	XCSE
GENMAB A/S	14-Apr-2025	4:47:01 PM	6	1269.50	XCSE
GENMAB A/S	14-Apr-2025	4:47:14 PM	86	1269.50	XCSE
GENMAB A/S	14-Apr-2025	4:47:19 PM	12	1270.50	XCSE
GENMAB A/S	14-Apr-2025	4:47:19 PM	10	1270.50	XCSE
GENMAB A/S	14-Apr-2025	4:47:19 PM	10	1270.50	XCSE
GENMAB A/S	14-Apr-2025	4:47:19 PM	21	1270.50	XCSE
GENMAB A/S	14-Apr-2025	4:47:19 PM	35	1270.50	XCSE
GENMAB A/S	14-Apr-2025	4:47:19 PM	24	1270.50	XCSE
GENMAB A/S	14-Apr-2025	4:47:19 PM	19	1270.00	TQEX

Exhibit 99.1(a)

APPENDIX Share buy-back programme - Specification for April 14 – April 18, 2025

GENMAB A/S	14-Apr-2025	4:47:19 PM	19	1270.00	CEUX
GENMAB A/S	14-Apr-2025	4:47:19 PM	1	1270.00	CEUX
GENMAB A/S	14-Apr-2025	4:47:20 PM	35	1270.50	XCSE
GENMAB A/S	14-Apr-2025	4:47:20 PM	31	1270.50	XCSE
GENMAB A/S	14-Apr-2025	4:47:20 PM	11	1270.50	XCSE
GENMAB A/S	14-Apr-2025	4:47:20 PM	35	1270.00	XCSE
GENMAB A/S	14-Apr-2025	4:47:20 PM	36	1270.50	CEUX
GENMAB A/S	14-Apr-2025	4:47:20 PM	1	1270.50	CEUX
GENMAB A/S	14-Apr-2025	4:47:20 PM	26	1270.50	CEUX
GENMAB A/S	14-Apr-2025	4:47:20 PM	36	1270.50	CEUX
GENMAB A/S	14-Apr-2025	4:47:21 PM	36	1270.50	CEUX
GENMAB A/S	14-Apr-2025	4:47:21 PM	5	1270.50	CEUX
GENMAB A/S	14-Apr-2025	4:47:21 PM	5	1270.50	CEUX
GENMAB A/S	14-Apr-2025	4:47:22 PM	6	1270.50	CEUX
GENMAB A/S	14-Apr-2025	4:47:22 PM	5	1270.50	CEUX
GENMAB A/S	14-Apr-2025	4:47:22 PM	5	1270.50	CEUX
GENMAB A/S	14-Apr-2025	4:47:22 PM	9	1270.50	CEUX
GENMAB A/S	14-Apr-2025	4:47:22 PM	32	1270.50	CEUX
GENMAB A/S	14-Apr-2025	4:47:24 PM	5	1270.00	XCSE
GENMAB A/S	14-Apr-2025	4:47:24 PM	46	1270.00	XCSE
GENMAB A/S	14-Apr-2025	4:47:24 PM	12	1270.00	TQEX
GENMAB A/S	14-Apr-2025	4:47:24 PM	14	1270.00	CEUX
GENMAB A/S	14-Apr-2025	4:47:24 PM	34	1270.00	CEUX
GENMAB A/S	14-Apr-2025	4:47:25 PM	15	1270.00	CEUX
GENMAB A/S	14-Apr-2025	4:47:25 PM	1	1270.00	CEUX
GENMAB A/S	14-Apr-2025	4:47:27 PM	53	1269.50	XCSE
GENMAB A/S	14-Apr-2025	4:47:54 PM	72	1269.50	XCSE
GENMAB A/S	14-Apr-2025	4:47:54 PM	10	1270.00	XCSE
GENMAB A/S	14-Apr-2025	4:47:54 PM	13	1270.00	XCSE
GENMAB A/S	14-Apr-2025	4:47:54 PM	64	1270.00	XCSE
GENMAB A/S	14-Apr-2025	4:47:54 PM	23	1270.00	XCSE
GENMAB A/S	14-Apr-2025	4:47:54 PM	6	1269.50	AQEU
GENMAB A/S	14-Apr-2025	4:47:55 PM	2	1269.50	AQEU
GENMAB A/S	14-Apr-2025	4:47:59 PM	4	1269.50	AQEU
GENMAB A/S	14-Apr-2025	4:48:04 PM	3	1269.50	AQEU
GENMAB A/S	14-Apr-2025	4:48:09 PM	3	1269.50	AQEU
GENMAB A/S	14-Apr-2025	4:48:14 PM	3	1269.50	AQEU
GENMAB A/S	14-Apr-2025	4:48:17 PM	5	1269.50	AQEU
GENMAB A/S	14-Apr-2025	4:48:18 PM	82	1268.50	XCSE
GENMAB A/S	14-Apr-2025	4:48:18 PM	2	1269.00	TQEX
GENMAB A/S	14-Apr-2025	4:48:18 PM	3	1269.50	CEUX
GENMAB A/S	14-Apr-2025	4:48:18 PM	1	1269.00	CEUX
GENMAB A/S	14-Apr-2025	4:48:19 PM	20	1269.00	TQEX

Exhibit 99.1(a)

APPENDIX Share buy-back programme - Specification for April 14 – April 18, 2025

GENMAB A/S	14-Apr-2025	4:48:19 PM	2	1269.00	TQEX
GENMAB A/S	14-Apr-2025	4:48:24 PM	1	1269.00	TQEX
GENMAB A/S	14-Apr-2025	4:48:29 PM	10	1269.00	CEUX
GENMAB A/S	14-Apr-2025	4:48:34 PM	79	1269.00	XCSE
GENMAB A/S	14-Apr-2025	4:48:41 PM	2	1269.00	CEUX
GENMAB A/S	14-Apr-2025	4:49:00 PM	88	1270.00	XCSE
GENMAB A/S	14-Apr-2025	4:49:06 PM	64	1271.50	XCSE
GENMAB A/S	14-Apr-2025	4:49:06 PM	13	1271.50	XCSE
GENMAB A/S	14-Apr-2025	4:49:06 PM	36	1271.50	CEUX
GENMAB A/S	14-Apr-2025	4:49:06 PM	2	1271.50	CEUX
GENMAB A/S	14-Apr-2025	4:49:06 PM	29	1271.50	CEUX
GENMAB A/S	14-Apr-2025	4:49:07 PM	100	1271.50	XCSE
GENMAB A/S	14-Apr-2025	4:49:14 PM	25	1271.00	TQEX
GENMAB A/S	14-Apr-2025	4:49:14 PM	43	1271.00	CEUX
GENMAB A/S	14-Apr-2025	4:49:14 PM	1	1271.00	CEUX
GENMAB A/S	14-Apr-2025	4:49:14 PM	40	1271.00	CEUX
GENMAB A/S	14-Apr-2025	4:49:38 PM	53	1272.50	XCSE
GENMAB A/S	14-Apr-2025	4:49:48 PM	34	1273.50	CEUX
GENMAB A/S	14-Apr-2025	4:49:48 PM	6	1273.50	CEUX
GENMAB A/S	14-Apr-2025	4:49:49 PM	66	1273.00	XCSE
GENMAB A/S	14-Apr-2025	4:49:49 PM	15	1273.50	XCSE
GENMAB A/S	14-Apr-2025	4:49:49 PM	2	1273.50	XCSE
GENMAB A/S	14-Apr-2025	4:49:49 PM	13	1273.50	XCSE
GENMAB A/S	14-Apr-2025	4:49:49 PM	11	1273.50	XCSE
GENMAB A/S	14-Apr-2025	4:49:49 PM	64	1273.50	XCSE
GENMAB A/S	14-Apr-2025	4:49:49 PM	7	1273.50	XCSE
GENMAB A/S	14-Apr-2025	4:49:49 PM	48	1273.50	XCSE
GENMAB A/S	14-Apr-2025	4:49:49 PM	25	1273.00	TQEX
GENMAB A/S	14-Apr-2025	4:49:49 PM	44	1273.50	CEUX
GENMAB A/S	14-Apr-2025	4:49:49 PM	36	1273.50	CEUX
GENMAB A/S	14-Apr-2025	4:49:49 PM	26	1273.50	AQEU
GENMAB A/S	14-Apr-2025	4:50:00 PM	13	1273.50	TQEX
GENMAB A/S	14-Apr-2025	4:50:04 PM	16	1273.00	XCSE
GENMAB A/S	14-Apr-2025	4:50:04 PM	14	1273.50	TQEX
GENMAB A/S	14-Apr-2025	4:50:12 PM	35	1273.00	XCSE
GENMAB A/S	14-Apr-2025	4:50:12 PM	33	1273.00	XCSE
GENMAB A/S	14-Apr-2025	4:50:12 PM	44	1273.00	XCSE
GENMAB A/S	14-Apr-2025	4:50:12 PM	47	1272.50	XCSE
GENMAB A/S	14-Apr-2025	4:50:12 PM	4	1272.50	TQEX
GENMAB A/S	14-Apr-2025	4:50:12 PM	2	1272.50	TQEX
GENMAB A/S	14-Apr-2025	4:50:12 PM	4	1272.50	TQEX
GENMAB A/S	14-Apr-2025	4:50:12 PM	2	1272.50	TQEX
GENMAB A/S	14-Apr-2025	4:50:12 PM	4	1272.50	TQEX

Exhibit 99.1(a)

APPENDIX Share buy-back programme - Specification for April 14 – April 18, 2025

GENMAB A/S	14-Apr-2025	4:50:12 PM	10	1272.50	TQEX
GENMAB A/S	14-Apr-2025	4:50:12 PM	7	1273.00	CEUX
GENMAB A/S	14-Apr-2025	4:50:12 PM	36	1273.00	CEUX
GENMAB A/S	14-Apr-2025	4:50:12 PM	8	1273.00	CEUX
GENMAB A/S	14-Apr-2025	4:50:12 PM	4	1273.00	CEUX
GENMAB A/S	14-Apr-2025	4:50:12 PM	15	1272.50	CEUX
GENMAB A/S	14-Apr-2025	4:50:12 PM	40	1272.50	CEUX
GENMAB A/S	14-Apr-2025	4:50:12 PM	2	1272.50	CEUX
GENMAB A/S	14-Apr-2025	4:50:12 PM	13	1272.50	CEUX
GENMAB A/S	14-Apr-2025	4:50:12 PM	7	1272.50	CEUX
GENMAB A/S	14-Apr-2025	4:50:12 PM	9	1272.50	CEUX
GENMAB A/S	14-Apr-2025	4:50:12 PM	35	1272.50	AQEU
GENMAB A/S	14-Apr-2025	4:50:31 PM	51	1272.50	XCSE
GENMAB A/S	14-Apr-2025	4:50:31 PM	10	1273.00	XCSE
GENMAB A/S	14-Apr-2025	4:50:31 PM	13	1273.00	XCSE
GENMAB A/S	14-Apr-2025	4:50:31 PM	11	1273.00	XCSE
GENMAB A/S	14-Apr-2025	4:50:31 PM	32	1273.00	XCSE
GENMAB A/S	14-Apr-2025	4:50:31 PM	6	1273.00	CEUX
GENMAB A/S	14-Apr-2025	4:50:31 PM	6	1273.00	CEUX
GENMAB A/S	14-Apr-2025	4:50:31 PM	5	1273.00	CEUX
GENMAB A/S	14-Apr-2025	4:50:34 PM	6	1273.00	CEUX
GENMAB A/S	14-Apr-2025	4:50:34 PM	6	1273.00	CEUX
GENMAB A/S	14-Apr-2025	4:50:34 PM	5	1273.00	CEUX
GENMAB A/S	14-Apr-2025	4:50:48 PM	3	1273.50	XCSE
GENMAB A/S	14-Apr-2025	4:50:48 PM	64	1273.50	XCSE
GENMAB A/S	14-Apr-2025	4:50:48 PM	13	1273.50	XCSE
GENMAB A/S	14-Apr-2025	4:50:48 PM	8	1273.50	XCSE
GENMAB A/S	14-Apr-2025	4:50:48 PM	47	1273.00	XCSE
GENMAB A/S	14-Apr-2025	4:50:48 PM	5	1273.50	CEUX
GENMAB A/S	14-Apr-2025	4:50:48 PM	20	1273.50	CEUX
GENMAB A/S	14-Apr-2025	4:50:50 PM	9	1273.50	XCSE
GENMAB A/S	14-Apr-2025	4:50:53 PM	5	1273.50	CEUX
GENMAB A/S	14-Apr-2025	4:50:53 PM	6	1273.50	CEUX
GENMAB A/S	14-Apr-2025	4:50:53 PM	5	1273.50	CEUX
GENMAB A/S	14-Apr-2025	4:51:14 PM	61	1273.50	XCSE
GENMAB A/S	14-Apr-2025	4:51:33 PM	55	1273.50	CEUX
GENMAB A/S	14-Apr-2025	4:51:39 PM	42	1273.50	XCSE
GENMAB A/S	14-Apr-2025	4:51:39 PM	40	1273.50	XCSE
GENMAB A/S	14-Apr-2025	4:51:39 PM	36	1274.00	CEUX
GENMAB A/S	14-Apr-2025	4:51:39 PM	5	1274.00	CEUX
GENMAB A/S	14-Apr-2025	4:51:39 PM	6	1274.00	CEUX
GENMAB A/S	14-Apr-2025	4:51:39 PM	6	1274.00	CEUX
GENMAB A/S	14-Apr-2025	4:51:40 PM	20	1273.50	CEUX

Exhibit 99.1(a)

APPENDIX Share buy-back programme - Specification for April 14 – April 18, 2025

GENMAB A/S	14-Apr-2025	4:51:46 PM	36	1273.50	CEUX
GENMAB A/S	14-Apr-2025	4:51:46 PM	36	1273.50	CEUX
GENMAB A/S	14-Apr-2025	4:51:46 PM	5	1273.50	CEUX
GENMAB A/S	14-Apr-2025	4:51:46 PM	6	1273.50	CEUX
GENMAB A/S	14-Apr-2025	4:51:46 PM	5	1273.50	CEUX
GENMAB A/S	14-Apr-2025	4:51:46 PM	36	1273.50	CEUX
GENMAB A/S	14-Apr-2025	4:51:46 PM	6	1273.50	CEUX
GENMAB A/S	14-Apr-2025	4:51:46 PM	5	1273.50	CEUX
GENMAB A/S	14-Apr-2025	4:51:46 PM	6	1273.50	CEUX
GENMAB A/S	14-Apr-2025	4:51:47 PM	32	1272.50	XCSE
GENMAB A/S	14-Apr-2025	4:51:47 PM	6	1273.50	CEUX
GENMAB A/S	14-Apr-2025	4:51:47 PM	5	1273.50	CEUX
GENMAB A/S	14-Apr-2025	4:51:47 PM	5	1273.50	CEUX
GENMAB A/S	14-Apr-2025	4:51:47 PM	36	1273.50	CEUX
GENMAB A/S	14-Apr-2025	4:51:47 PM	5	1273.50	CEUX
GENMAB A/S	14-Apr-2025	4:51:47 PM	5	1273.50	CEUX
GENMAB A/S	14-Apr-2025	4:51:47 PM	5	1273.50	CEUX
GENMAB A/S	14-Apr-2025	4:51:52 PM	57	1272.50	XCSE
GENMAB A/S	14-Apr-2025	4:51:52 PM	57	1272.50	CEUX
GENMAB A/S	14-Apr-2025	4:52:00 PM	25	1272.50	XCSE
GENMAB A/S	14-Apr-2025	4:52:00 PM	13	1273.00	AQEU
GENMAB A/S	14-Apr-2025	4:52:10 PM	85	1273.00	XCSE
GENMAB A/S	14-Apr-2025	4:52:11 PM	12	1273.50	XCSE
GENMAB A/S	14-Apr-2025	4:52:11 PM	10	1273.50	XCSE
GENMAB A/S	14-Apr-2025	4:52:11 PM	13	1273.50	XCSE
GENMAB A/S	14-Apr-2025	4:52:11 PM	64	1273.50	XCSE
GENMAB A/S	14-Apr-2025	4:52:11 PM	11	1273.50	XCSE
GENMAB A/S	14-Apr-2025	4:52:12 PM	41	1272.50	AQEU
GENMAB A/S	14-Apr-2025	4:52:13 PM	5	1273.50	CEUX
GENMAB A/S	14-Apr-2025	4:52:13 PM	6	1273.50	CEUX
GENMAB A/S	14-Apr-2025	4:52:13 PM	5	1273.50	CEUX
GENMAB A/S	14-Apr-2025	4:52:13 PM	20	1273.50	CEUX
GENMAB A/S	14-Apr-2025	4:52:24 PM	27	1271.50	XCSE
GENMAB A/S	14-Apr-2025	4:52:24 PM	39	1272.50	TQEX
GENMAB A/S	14-Apr-2025	4:52:24 PM	10	1272.50	CEUX
GENMAB A/S	14-Apr-2025	4:52:24 PM	30	1272.50	CEUX
GENMAB A/S	14-Apr-2025	4:52:24 PM	2	1273.00	CEUX
GENMAB A/S	14-Apr-2025	4:52:24 PM	2	1272.50	AQEU
GENMAB A/S	14-Apr-2025	4:52:24 PM	2	1272.50	AQEU
GENMAB A/S	14-Apr-2025	4:52:25 PM	15	1272.50	AQEU
GENMAB A/S	14-Apr-2025	4:52:25 PM	2	1272.50	AQEU
GENMAB A/S	14-Apr-2025	4:52:25 PM	3	1272.50	AQEU
GENMAB A/S	14-Apr-2025	4:52:25 PM	2	1272.50	AQEU

Exhibit 99.1(a)

APPENDIX Share buy-back programme - Specification for April 14 – April 18, 2025

GENMAB A/S	14-Apr-2025	4:52:25 PM	7	1272.50	AQEU
GENMAB A/S	14-Apr-2025	4:52:27 PM	13	1272.50	XCSE
GENMAB A/S	14-Apr-2025	4:52:31 PM	15	1272.50	XCSE
GENMAB A/S	14-Apr-2025	4:52:34 PM	9	1273.00	CEUX
GENMAB A/S	14-Apr-2025	4:52:34 PM	6	1273.00	CEUX
GENMAB A/S	14-Apr-2025	4:52:34 PM	6	1273.00	CEUX
GENMAB A/S	14-Apr-2025	4:52:34 PM	23	1272.50	CEUX
GENMAB A/S	14-Apr-2025	4:52:34 PM	8	1272.50	CEUX
GENMAB A/S	14-Apr-2025	4:52:35 PM	14	1272.50	AQEU
GENMAB A/S	14-Apr-2025	4:53:02 PM	64	1272.50	XCSE
GENMAB A/S	14-Apr-2025	4:53:02 PM	11	1272.50	XCSE
GENMAB A/S	14-Apr-2025	4:53:02 PM	11	1272.50	XCSE
GENMAB A/S	14-Apr-2025	4:53:02 PM	11	1272.50	XCSE
GENMAB A/S	14-Apr-2025	4:53:02 PM	36	1272.50	CEUX
GENMAB A/S	14-Apr-2025	4:53:02 PM	6	1272.50	CEUX
GENMAB A/S	14-Apr-2025	4:53:02 PM	6	1272.50	CEUX
GENMAB A/S	14-Apr-2025	4:53:02 PM	6	1272.50	CEUX
GENMAB A/S	14-Apr-2025	4:53:02 PM	1	1272.50	AQEU
GENMAB A/S	14-Apr-2025	4:53:02 PM	20	1272.50	AQEU
GENMAB A/S	14-Apr-2025	4:53:04 PM	20	1273.00	CEUX
GENMAB A/S	14-Apr-2025	4:53:14 PM	82	1273.00	XCSE
GENMAB A/S	14-Apr-2025	4:53:30 PM	22	1274.50	CEUX
GENMAB A/S	14-Apr-2025	4:54:04 PM	83	1274.50	TQEX
GENMAB A/S	14-Apr-2025	4:54:04 PM	29	1274.50	CEUX
GENMAB A/S	14-Apr-2025	4:54:07 PM	69	1274.00	XCSE
GENMAB A/S	14-Apr-2025	4:54:07 PM	15	1274.00	XCSE
GENMAB A/S	14-Apr-2025	4:54:07 PM	36	1274.50	CEUX
GENMAB A/S	14-Apr-2025	4:54:07 PM	56	1274.50	AQEU
GENMAB A/S	14-Apr-2025	4:54:08 PM	64	1274.50	XCSE
GENMAB A/S	14-Apr-2025	4:54:08 PM	11	1274.50	XCSE
GENMAB A/S	14-Apr-2025	4:54:08 PM	13	1274.50	XCSE
GENMAB A/S	14-Apr-2025	4:54:08 PM	64	1274.50	XCSE
GENMAB A/S	14-Apr-2025	4:54:08 PM	13	1274.50	XCSE
GENMAB A/S	14-Apr-2025	4:54:08 PM	11	1274.50	XCSE
GENMAB A/S	14-Apr-2025	4:54:08 PM	36	1274.50	CEUX
GENMAB A/S	14-Apr-2025	4:54:08 PM	6	1274.50	CEUX
GENMAB A/S	14-Apr-2025	4:54:08 PM	5	1274.50	CEUX
GENMAB A/S	14-Apr-2025	4:54:08 PM	6	1274.50	CEUX
GENMAB A/S	14-Apr-2025	4:54:08 PM	20	1274.50	CEUX
GENMAB A/S	14-Apr-2025	4:54:09 PM	1	1274.50	XCSE
GENMAB A/S	14-Apr-2025	4:54:09 PM	11	1274.50	XCSE
GENMAB A/S	14-Apr-2025	4:54:09 PM	31	1274.50	XCSE
GENMAB A/S	14-Apr-2025	4:54:09 PM	64	1274.50	XCSE

Exhibit 99.1(a)

APPENDIX Share buy-back programme - Specification for April 14 – April 18, 2025

GENMAB A/S	14-Apr-2025	4:54:18 PM	49	1274.00	XCSE
GENMAB A/S	14-Apr-2025	4:54:18 PM	40	1274.00	XCSE
GENMAB A/S	14-Apr-2025	4:54:18 PM	36	1274.50	CEUX
GENMAB A/S	14-Apr-2025	4:54:30 PM	80	1274.00	XCSE
GENMAB A/S	14-Apr-2025	4:54:30 PM	9	1274.00	XCSE
GENMAB A/S	14-Apr-2025	4:54:32 PM	30	1273.50	CEUX
GENMAB A/S	14-Apr-2025	4:54:42 PM	88	1273.00	XCSE
GENMAB A/S	14-Apr-2025	4:54:48 PM	1	1274.00	XCSE
GENMAB A/S	15-Apr-2025	9:41:56 AM	89	1292.00	CEUX
GENMAB A/S	15-Apr-2025	9:42:03 AM	80	1291.50	XCSE
GENMAB A/S	15-Apr-2025	9:42:03 AM	72	1291.50	TQEX
GENMAB A/S	15-Apr-2025	9:42:29 AM	60	1291.50	XCSE
GENMAB A/S	15-Apr-2025	9:42:29 AM	53	1291.50	TQEX
GENMAB A/S	15-Apr-2025	9:42:29 AM	78	1291.00	CEUX
GENMAB A/S	15-Apr-2025	9:42:29 AM	83	1291.00	AQEU
GENMAB A/S	15-Apr-2025	9:42:30 AM	77	1290.50	XCSE
GENMAB A/S	15-Apr-2025	9:45:16 AM	5	1290.50	XCSE
GENMAB A/S	15-Apr-2025	9:45:16 AM	27	1290.50	XCSE
GENMAB A/S	15-Apr-2025	9:45:30 AM	27	1291.00	XCSE
GENMAB A/S	15-Apr-2025	9:46:20 AM	25	1292.50	XCSE
GENMAB A/S	15-Apr-2025	9:46:20 AM	10	1292.00	AQEU
GENMAB A/S	15-Apr-2025	9:46:30 AM	16	1292.00	AQEU
GENMAB A/S	15-Apr-2025	9:47:20 AM	21	1293.50	AQEU
GENMAB A/S	15-Apr-2025	9:47:30 AM	43	1294.00	TQEX
GENMAB A/S	15-Apr-2025	9:47:48 AM	62	1294.00	XCSE
GENMAB A/S	15-Apr-2025	9:50:14 AM	62	1294.00	XCSE
GENMAB A/S	15-Apr-2025	9:50:14 AM	40	1293.00	XCSE
GENMAB A/S	15-Apr-2025	9:50:14 AM	43	1293.00	TQEX
GENMAB A/S	15-Apr-2025	9:50:14 AM	34	1292.00	TQEX
GENMAB A/S	15-Apr-2025	9:50:14 AM	84	1294.00	CEUX
GENMAB A/S	15-Apr-2025	9:50:14 AM	85	1293.00	CEUX
GENMAB A/S	15-Apr-2025	9:50:14 AM	8	1292.00	CEUX
GENMAB A/S	15-Apr-2025	9:50:14 AM	66	1292.00	CEUX
GENMAB A/S	15-Apr-2025	9:50:14 AM	23	1293.50	AQEU
GENMAB A/S	15-Apr-2025	9:50:14 AM	44	1292.50	AQEU
GENMAB A/S	15-Apr-2025	9:50:20 AM	6	1292.00	TQEX
GENMAB A/S	15-Apr-2025	9:50:20 AM	19	1292.00	CEUX
GENMAB A/S	15-Apr-2025	9:50:21 AM	22	1292.00	AQEU
GENMAB A/S	15-Apr-2025	9:50:22 AM	38	1292.00	CEUX
GENMAB A/S	15-Apr-2025	9:51:08 AM	28	1292.00	CEUX
GENMAB A/S	15-Apr-2025	9:53:07 AM	30	1291.50	XCSE
GENMAB A/S	15-Apr-2025	9:53:07 AM	4	1291.50	XCSE
GENMAB A/S	15-Apr-2025	9:53:39 AM	22	1290.50	CEUX

Exhibit 99.1(a)

APPENDIX Share buy-back programme - Specification for April 14 – April 18, 2025

GENMAB A/S	15-Apr-2025	9:54:11 AM	22	1290.50	CEUX
GENMAB A/S	15-Apr-2025	9:55:10 AM	22	1290.50	CEUX
GENMAB A/S	15-Apr-2025	9:56:53 AM	24	1291.00	AQEU
GENMAB A/S	15-Apr-2025	9:56:53 AM	3	1291.00	AQEU
GENMAB A/S	15-Apr-2025	9:57:09 AM	39	1290.50	XCSE
GENMAB A/S	15-Apr-2025	9:57:09 AM	36	1291.00	TQEX
GENMAB A/S	15-Apr-2025	9:57:09 AM	24	1290.50	CEUX
GENMAB A/S	15-Apr-2025	9:57:09 AM	30	1291.00	AQEU
GENMAB A/S	15-Apr-2025	9:57:26 AM	87	1290.00	XCSE
GENMAB A/S	15-Apr-2025	9:59:40 AM	25	1292.00	CEUX
GENMAB A/S	15-Apr-2025	9:59:51 AM	89	1292.50	XCSE
GENMAB A/S	15-Apr-2025	9:59:51 AM	29	1292.50	XCSE
GENMAB A/S	15-Apr-2025	9:59:51 AM	13	1292.50	XCSE
GENMAB A/S	15-Apr-2025	9:59:51 AM	16	1292.50	XCSE
GENMAB A/S	15-Apr-2025	9:59:51 AM	30	1292.50	TQEX
GENMAB A/S	15-Apr-2025	9:59:51 AM	13	1292.50	TQEX
GENMAB A/S	15-Apr-2025	9:59:51 AM	7	1292.50	CEUX
GENMAB A/S	15-Apr-2025	9:59:51 AM	8	1292.50	CEUX
GENMAB A/S	15-Apr-2025	9:59:51 AM	1	1292.50	AQEU
GENMAB A/S	15-Apr-2025	9:59:51 AM	1	1292.50	AQEU
GENMAB A/S	15-Apr-2025	9:59:52 AM	7	1292.50	CEUX
GENMAB A/S	15-Apr-2025	9:59:57 AM	15	1292.50	XCSE
GENMAB A/S	15-Apr-2025	10:00:00 AM	15	1292.50	CEUX
GENMAB A/S	15-Apr-2025	10:00:00 AM	8	1292.50	AQEU
GENMAB A/S	15-Apr-2025	10:00:09 AM	45	1292.50	XCSE
GENMAB A/S	15-Apr-2025	10:00:09 AM	40	1292.50	XCSE
GENMAB A/S	15-Apr-2025	10:00:09 AM	47	1292.50	XCSE
GENMAB A/S	15-Apr-2025	10:00:09 AM	25	1293.00	TQEX
GENMAB A/S	15-Apr-2025	10:00:09 AM	89	1293.00	CEUX
GENMAB A/S	15-Apr-2025	10:00:13 AM	24	1292.50	XCSE
GENMAB A/S	15-Apr-2025	10:00:13 AM	15	1292.50	AQEU
GENMAB A/S	15-Apr-2025	10:00:15 AM	66	1292.00	CEUX
GENMAB A/S	15-Apr-2025	10:00:16 AM	90	1291.00	XCSE
GENMAB A/S	15-Apr-2025	10:00:16 AM	35	1292.00	XCSE
GENMAB A/S	15-Apr-2025	10:00:16 AM	38	1292.00	XCSE
GENMAB A/S	15-Apr-2025	10:00:16 AM	19	1292.00	XCSE
GENMAB A/S	15-Apr-2025	10:00:16 AM	22	1292.00	XCSE
GENMAB A/S	15-Apr-2025	10:00:16 AM	33	1291.50	TQEX
GENMAB A/S	15-Apr-2025	10:00:17 AM	84	1291.50	XCSE
GENMAB A/S	15-Apr-2025	10:00:18 AM	15	1291.50	XCSE
GENMAB A/S	15-Apr-2025	10:00:18 AM	57	1291.50	XCSE
GENMAB A/S	15-Apr-2025	10:00:18 AM	47	1291.50	XCSE
GENMAB A/S	15-Apr-2025	10:00:26 AM	38	1291.00	XCSE

Exhibit 99.1(a)

APPENDIX Share buy-back programme - Specification for April 14 – April 18, 2025

GENMAB A/S	15-Apr-2025	10:00:26 AM	35	1291.00	XCSE
GENMAB A/S	15-Apr-2025	10:00:26 AM	16	1291.00	XCSE
GENMAB A/S	15-Apr-2025	10:00:26 AM	16	1291.00	XCSE
GENMAB A/S	15-Apr-2025	10:00:26 AM	57	1291.00	XCSE
GENMAB A/S	15-Apr-2025	10:00:26 AM	34	1291.00	XCSE
GENMAB A/S	15-Apr-2025	10:00:26 AM	68	1291.00	CEUX
GENMAB A/S	15-Apr-2025	10:00:26 AM	23	1291.00	CEUX
GENMAB A/S	15-Apr-2025	10:00:26 AM	27	1291.00	AQEU
GENMAB A/S	15-Apr-2025	10:01:21 AM	84	1291.00	XCSE
GENMAB A/S	15-Apr-2025	10:01:28 AM	24	1291.00	CEUX
GENMAB A/S	15-Apr-2025	10:02:45 AM	25	1292.00	CEUX
GENMAB A/S	15-Apr-2025	10:02:52 AM	51	1292.00	CEUX
GENMAB A/S	15-Apr-2025	10:03:09 AM	26	1292.50	XCSE
GENMAB A/S	15-Apr-2025	10:03:09 AM	38	1292.50	XCSE
GENMAB A/S	15-Apr-2025	10:03:09 AM	13	1292.50	XCSE
GENMAB A/S	15-Apr-2025	10:03:09 AM	15	1292.50	XCSE
GENMAB A/S	15-Apr-2025	10:03:09 AM	22	1292.50	XCSE
GENMAB A/S	15-Apr-2025	10:03:09 AM	16	1292.50	XCSE
GENMAB A/S	15-Apr-2025	10:03:09 AM	17	1292.50	XCSE
GENMAB A/S	15-Apr-2025	10:03:09 AM	26	1292.50	XCSE
GENMAB A/S	15-Apr-2025	10:03:09 AM	14	1292.00	CEUX
GENMAB A/S	15-Apr-2025	10:03:59 AM	91	1294.50	XCSE
GENMAB A/S	15-Apr-2025	10:03:59 AM	32	1294.50	XCSE
GENMAB A/S	15-Apr-2025	10:03:59 AM	13	1294.50	XCSE
GENMAB A/S	15-Apr-2025	10:03:59 AM	39	1294.50	XCSE
GENMAB A/S	15-Apr-2025	10:03:59 AM	30	1294.50	XCSE
GENMAB A/S	15-Apr-2025	10:03:59 AM	88	1294.00	CEUX
GENMAB A/S	15-Apr-2025	10:03:59 AM	35	1294.50	AQEU
GENMAB A/S	15-Apr-2025	10:04:12 AM	86	1293.50	XCSE
GENMAB A/S	15-Apr-2025	10:04:12 AM	26	1293.50	AQEU
GENMAB A/S	15-Apr-2025	10:04:36 AM	90	1292.50	XCSE
GENMAB A/S	15-Apr-2025	10:04:36 AM	89	1293.00	CEUX
GENMAB A/S	15-Apr-2025	10:04:36 AM	15	1292.50	AQEU
GENMAB A/S	15-Apr-2025	10:04:36 AM	10	1292.50	AQEU
GENMAB A/S	15-Apr-2025	10:04:45 AM	25	1292.00	TQEX
GENMAB A/S	15-Apr-2025	10:04:45 AM	89	1292.00	CEUX
GENMAB A/S	15-Apr-2025	10:04:47 AM	86	1291.00	XCSE
GENMAB A/S	15-Apr-2025	10:05:22 AM	15	1290.50	CEUX
GENMAB A/S	15-Apr-2025	10:06:03 AM	3	1291.50	XCSE
GENMAB A/S	15-Apr-2025	10:06:41 AM	50	1291.50	XCSE
GENMAB A/S	15-Apr-2025	10:06:41 AM	31	1291.50	XCSE
GENMAB A/S	15-Apr-2025	10:06:41 AM	78	1291.50	CEUX
GENMAB A/S	15-Apr-2025	10:07:21 AM	37	1290.00	XCSE

Exhibit 99.1(a)

APPENDIX Share buy-back programme - Specification for April 14 – April 18, 2025

GENMAB A/S	15-Apr-2025	10:07:21 AM	61	1290.50	CEUX
GENMAB A/S	15-Apr-2025	10:07:21 AM	13	1290.50	CEUX
GENMAB A/S	15-Apr-2025	10:07:40 AM	37	1291.00	XCSE
GENMAB A/S	15-Apr-2025	10:07:40 AM	9	1291.00	XCSE
GENMAB A/S	15-Apr-2025	10:09:21 AM	87	1291.50	XCSE
GENMAB A/S	15-Apr-2025	10:10:05 AM	39	1291.50	XCSE
GENMAB A/S	15-Apr-2025	10:10:05 AM	27	1291.50	XCSE
GENMAB A/S	15-Apr-2025	10:10:05 AM	20	1291.50	XCSE
GENMAB A/S	15-Apr-2025	10:10:05 AM	28	1291.50	XCSE
GENMAB A/S	15-Apr-2025	10:10:05 AM	25	1291.00	TQEX
GENMAB A/S	15-Apr-2025	10:10:07 AM	52	1291.00	XCSE
GENMAB A/S	15-Apr-2025	10:10:07 AM	25	1291.00	AQEU
GENMAB A/S	15-Apr-2025	10:11:07 AM	22	1291.50	CEUX
GENMAB A/S	15-Apr-2025	10:11:21 AM	90	1291.00	XCSE
GENMAB A/S	15-Apr-2025	10:11:21 AM	63	1291.50	CEUX
GENMAB A/S	15-Apr-2025	10:11:26 AM	58	1291.00	XCSE
GENMAB A/S	15-Apr-2025	10:11:28 AM	44	1290.50	CEUX
GENMAB A/S	15-Apr-2025	10:11:46 AM	48	1290.00	XCSE
GENMAB A/S	15-Apr-2025	10:11:46 AM	25	1290.00	TQEX
GENMAB A/S	15-Apr-2025	10:11:46 AM	37	1290.00	AQEU
GENMAB A/S	15-Apr-2025	10:11:47 AM	80	1289.50	CEUX
GENMAB A/S	15-Apr-2025	10:12:03 AM	16	1289.50	XCSE
GENMAB A/S	15-Apr-2025	10:12:03 AM	19	1289.50	XCSE
GENMAB A/S	15-Apr-2025	10:12:03 AM	30	1289.50	XCSE
GENMAB A/S	15-Apr-2025	10:12:12 AM	16	1290.00	XCSE
GENMAB A/S	15-Apr-2025	10:12:12 AM	15	1290.00	TQEX
GENMAB A/S	15-Apr-2025	10:13:20 AM	13	1291.50	XCSE
GENMAB A/S	15-Apr-2025	10:13:20 AM	24	1291.50	XCSE
GENMAB A/S	15-Apr-2025	10:13:20 AM	15	1291.50	XCSE
GENMAB A/S	15-Apr-2025	10:13:50 AM	31	1292.00	XCSE
GENMAB A/S	15-Apr-2025	10:14:11 AM	25	1292.50	AQEU
GENMAB A/S	15-Apr-2025	10:14:50 AM	67	1293.50	XCSE
GENMAB A/S	15-Apr-2025	10:14:50 AM	24	1293.50	XCSE
GENMAB A/S	15-Apr-2025	10:15:10 AM	84	1293.00	XCSE
GENMAB A/S	15-Apr-2025	10:15:10 AM	26	1293.00	TQEX
GENMAB A/S	15-Apr-2025	10:15:10 AM	23	1293.00	CEUX
GENMAB A/S	15-Apr-2025	10:15:10 AM	61	1293.00	CEUX
GENMAB A/S	15-Apr-2025	10:15:10 AM	28	1292.50	AQEU
GENMAB A/S	15-Apr-2025	10:15:31 AM	58	1292.00	XCSE
GENMAB A/S	15-Apr-2025	10:15:31 AM	25	1292.00	TQEX
GENMAB A/S	15-Apr-2025	10:15:31 AM	85	1292.00	CEUX
GENMAB A/S	15-Apr-2025	10:15:32 AM	91	1292.00	XCSE
GENMAB A/S	15-Apr-2025	10:15:32 AM	89	1291.00	XCSE

Exhibit 99.1(a)

APPENDIX Share buy-back programme - Specification for April 14 – April 18, 2025

GENMAB A/S	15-Apr-2025	10:15:32 AM	79	1291.00	CEUX
GENMAB A/S	15-Apr-2025	10:15:46 AM	89	1290.50	XCSE
GENMAB A/S	15-Apr-2025	10:17:51 AM	21	1292.00	CEUX
GENMAB A/S	15-Apr-2025	10:18:31 AM	82	1292.00	XCSE
GENMAB A/S	15-Apr-2025	10:18:31 AM	3	1292.00	XCSE
GENMAB A/S	15-Apr-2025	10:18:31 AM	15	1292.00	CEUX
GENMAB A/S	15-Apr-2025	10:18:31 AM	28	1292.00	CEUX
GENMAB A/S	15-Apr-2025	10:18:50 AM	11	1292.00	TQEX
GENMAB A/S	15-Apr-2025	10:18:50 AM	20	1292.00	TQEX
GENMAB A/S	15-Apr-2025	10:18:50 AM	89	1292.00	CEUX
GENMAB A/S	15-Apr-2025	10:18:50 AM	28	1292.00	AQEU
GENMAB A/S	15-Apr-2025	10:19:00 AM	90	1291.50	XCSE
GENMAB A/S	15-Apr-2025	10:20:43 AM	16	1292.00	XCSE
GENMAB A/S	15-Apr-2025	10:20:43 AM	57	1292.00	XCSE
GENMAB A/S	15-Apr-2025	10:21:11 AM	84	1291.50	XCSE
GENMAB A/S	15-Apr-2025	10:21:11 AM	29	1291.50	TQEX
GENMAB A/S	15-Apr-2025	10:21:11 AM	7	1291.00	CEUX
GENMAB A/S	15-Apr-2025	10:21:11 AM	6	1291.00	CEUX
GENMAB A/S	15-Apr-2025	10:21:11 AM	18	1291.00	CEUX
GENMAB A/S	15-Apr-2025	10:21:11 AM	8	1291.00	CEUX
GENMAB A/S	15-Apr-2025	10:21:11 AM	28	1291.50	AQEU
GENMAB A/S	15-Apr-2025	10:22:25 AM	89	1291.50	XCSE
GENMAB A/S	15-Apr-2025	10:24:12 AM	15	1292.00	XCSE
GENMAB A/S	15-Apr-2025	10:24:12 AM	15	1292.00	XCSE
GENMAB A/S	15-Apr-2025	10:24:12 AM	34	1292.00	XCSE
GENMAB A/S	15-Apr-2025	10:24:12 AM	50	1292.00	XCSE
GENMAB A/S	15-Apr-2025	10:24:17 AM	13	1292.00	XCSE
GENMAB A/S	15-Apr-2025	10:24:17 AM	39	1292.00	XCSE
GENMAB A/S	15-Apr-2025	10:24:17 AM	31	1292.00	XCSE
GENMAB A/S	15-Apr-2025	10:25:01 AM	57	1292.50	XCSE
GENMAB A/S	15-Apr-2025	10:25:01 AM	20	1292.50	XCSE
GENMAB A/S	15-Apr-2025	10:25:01 AM	86	1292.00	XCSE
GENMAB A/S	15-Apr-2025	10:25:01 AM	87	1292.00	CEUX
GENMAB A/S	15-Apr-2025	10:25:01 AM	26	1292.00	AQEU
GENMAB A/S	15-Apr-2025	10:27:31 AM	54	1290.50	XCSE
GENMAB A/S	15-Apr-2025	10:27:31 AM	89	1291.00	CEUX
GENMAB A/S	15-Apr-2025	10:27:31 AM	25	1291.00	AQEU
GENMAB A/S	15-Apr-2025	10:28:21 AM	31	1290.50	XCSE
GENMAB A/S	15-Apr-2025	10:29:20 AM	59	1290.50	XCSE
GENMAB A/S	15-Apr-2025	10:29:20 AM	14	1290.50	XCSE
GENMAB A/S	15-Apr-2025	10:29:20 AM	15	1290.50	XCSE
GENMAB A/S	15-Apr-2025	10:30:01 AM	32	1289.50	XCSE
GENMAB A/S	15-Apr-2025	10:30:01 AM	89	1290.00	CEUX

Exhibit 99.1(a)

APPENDIX Share buy-back programme - Specification for April 14 – April 18, 2025

GENMAB A/S	15-Apr-2025	10:30:01 AM	32	1290.50	CEUX
GENMAB A/S	15-Apr-2025	10:30:06 AM	2	1291.00	TQEX
GENMAB A/S	15-Apr-2025	10:30:06 AM	6	1291.00	TQEX
GENMAB A/S	15-Apr-2025	10:30:06 AM	2	1291.00	TQEX
GENMAB A/S	15-Apr-2025	10:30:06 AM	10	1291.00	TQEX
GENMAB A/S	15-Apr-2025	10:30:06 AM	88	1291.50	CEUX
GENMAB A/S	15-Apr-2025	10:30:07 AM	49	1291.50	XCSE
GENMAB A/S	15-Apr-2025	10:30:07 AM	16	1291.50	XCSE
GENMAB A/S	15-Apr-2025	10:30:07 AM	46	1291.50	XCSE
GENMAB A/S	15-Apr-2025	10:30:45 AM	50	1291.50	XCSE
GENMAB A/S	15-Apr-2025	10:30:45 AM	5	1291.50	XCSE
GENMAB A/S	15-Apr-2025	10:30:45 AM	23	1291.50	XCSE
GENMAB A/S	15-Apr-2025	10:30:45 AM	15	1291.50	XCSE
GENMAB A/S	15-Apr-2025	10:30:45 AM	21	1291.50	XCSE
GENMAB A/S	15-Apr-2025	10:30:45 AM	10	1291.00	TQEX
GENMAB A/S	15-Apr-2025	10:30:45 AM	25	1291.00	AQEU
GENMAB A/S	15-Apr-2025	10:31:03 AM	49	1291.00	XCSE
GENMAB A/S	15-Apr-2025	10:31:03 AM	11	1291.00	XCSE
GENMAB A/S	15-Apr-2025	10:31:53 AM	16	1291.00	XCSE
GENMAB A/S	15-Apr-2025	10:32:45 AM	31	1291.00	TQEX
GENMAB A/S	15-Apr-2025	10:32:45 AM	8	1291.00	AQEU
GENMAB A/S	15-Apr-2025	10:32:49 AM	90	1290.50	XCSE
GENMAB A/S	15-Apr-2025	10:32:49 AM	13	1291.00	XCSE
GENMAB A/S	15-Apr-2025	10:32:49 AM	13	1291.00	XCSE
GENMAB A/S	15-Apr-2025	10:32:49 AM	39	1291.00	XCSE
GENMAB A/S	15-Apr-2025	10:32:49 AM	34	1291.00	XCSE
GENMAB A/S	15-Apr-2025	10:32:49 AM	15	1291.00	XCSE
GENMAB A/S	15-Apr-2025	10:32:49 AM	85	1290.50	CEUX
GENMAB A/S	15-Apr-2025	10:33:29 AM	6	1290.00	TQEX
GENMAB A/S	15-Apr-2025	10:33:29 AM	19	1290.00	TQEX
GENMAB A/S	15-Apr-2025	10:34:24 AM	88	1290.00	XCSE
GENMAB A/S	15-Apr-2025	10:34:51 AM	55	1289.50	XCSE
GENMAB A/S	15-Apr-2025	10:36:29 AM	32	1290.00	CEUX
GENMAB A/S	15-Apr-2025	10:36:30 AM	45	1290.50	XCSE
GENMAB A/S	15-Apr-2025	10:36:30 AM	8	1290.50	XCSE
GENMAB A/S	15-Apr-2025	10:36:30 AM	32	1290.50	XCSE
GENMAB A/S	15-Apr-2025	10:37:05 AM	42	1290.50	XCSE
GENMAB A/S	15-Apr-2025	10:37:05 AM	8	1290.50	CEUX
GENMAB A/S	15-Apr-2025	10:39:00 AM	28	1291.50	TQEX
GENMAB A/S	15-Apr-2025	10:39:52 AM	13	1291.50	XCSE
GENMAB A/S	15-Apr-2025	10:39:52 AM	9	1291.50	XCSE
GENMAB A/S	15-Apr-2025	10:39:52 AM	15	1291.50	XCSE
GENMAB A/S	15-Apr-2025	10:39:52 AM	15	1291.50	XCSE

Exhibit 99.1(a)

APPENDIX Share buy-back programme - Specification for April 14 – April 18, 2025

GENMAB A/S	15-Apr-2025	10:39:52 AM	65	1291.00	XCSE
GENMAB A/S	15-Apr-2025	10:39:52 AM	36	1291.50	CEUX
GENMAB A/S	15-Apr-2025	10:39:52 AM	1	1291.50	CEUX
GENMAB A/S	15-Apr-2025	10:39:52 AM	25	1291.50	CEUX
GENMAB A/S	15-Apr-2025	10:41:31 AM	22	1294.50	XCSE
GENMAB A/S	15-Apr-2025	10:41:32 AM	28	1295.00	XCSE
GENMAB A/S	15-Apr-2025	10:41:32 AM	40	1295.00	XCSE
GENMAB A/S	15-Apr-2025	10:41:46 AM	28	1295.50	TQEX
GENMAB A/S	15-Apr-2025	10:42:04 AM	12	1295.00	XCSE
GENMAB A/S	15-Apr-2025	10:42:06 AM	79	1295.00	XCSE
GENMAB A/S	15-Apr-2025	10:42:06 AM	39	1295.00	AQEU
GENMAB A/S	15-Apr-2025	10:42:12 AM	30	1294.50	TQEX
GENMAB A/S	15-Apr-2025	10:42:12 AM	22	1294.50	CEUX
GENMAB A/S	15-Apr-2025	10:42:12 AM	66	1294.50	CEUX
GENMAB A/S	15-Apr-2025	10:42:12 AM	20	1294.50	CEUX
GENMAB A/S	15-Apr-2025	10:42:13 AM	35	1295.00	XCSE
GENMAB A/S	15-Apr-2025	10:42:13 AM	16	1295.00	XCSE
GENMAB A/S	15-Apr-2025	10:43:49 AM	21	1296.00	CEUX
GENMAB A/S	15-Apr-2025	10:43:55 AM	16	1296.50	XCSE
GENMAB A/S	15-Apr-2025	10:45:05 AM	45	1297.00	XCSE
GENMAB A/S	15-Apr-2025	10:45:05 AM	25	1297.00	TQEX
GENMAB A/S	15-Apr-2025	10:45:05 AM	90	1297.00	CEUX
GENMAB A/S	15-Apr-2025	10:45:05 AM	9	1297.00	CEUX
GENMAB A/S	15-Apr-2025	10:45:05 AM	24	1297.00	CEUX
GENMAB A/S	15-Apr-2025	10:45:07 AM	4	1297.00	CEUX
GENMAB A/S	15-Apr-2025	10:45:08 AM	86	1296.50	XCSE
GENMAB A/S	15-Apr-2025	10:45:08 AM	56	1296.50	XCSE
GENMAB A/S	15-Apr-2025	10:45:08 AM	39	1297.00	XCSE
GENMAB A/S	15-Apr-2025	10:45:08 AM	14	1297.00	XCSE
GENMAB A/S	15-Apr-2025	10:45:08 AM	5	1297.00	XCSE
GENMAB A/S	15-Apr-2025	10:45:08 AM	8	1297.00	XCSE
GENMAB A/S	15-Apr-2025	10:45:08 AM	13	1297.00	XCSE
GENMAB A/S	15-Apr-2025	10:45:08 AM	44	1297.00	XCSE
GENMAB A/S	15-Apr-2025	10:45:08 AM	32	1296.50	CEUX
GENMAB A/S	15-Apr-2025	10:45:08 AM	22	1296.50	AQEU
GENMAB A/S	15-Apr-2025	10:45:08 AM	13	1296.50	AQEU
GENMAB A/S	15-Apr-2025	10:45:43 AM	18	1297.00	XCSE
GENMAB A/S	15-Apr-2025	10:46:43 AM	24	1296.50	AQEU
GENMAB A/S	15-Apr-2025	10:47:31 AM	88	1296.50	XCSE
GENMAB A/S	15-Apr-2025	10:48:14 AM	50	1296.50	XCSE
GENMAB A/S	15-Apr-2025	10:48:14 AM	36	1296.50	CEUX
GENMAB A/S	15-Apr-2025	10:48:18 AM	36	1296.50	CEUX
GENMAB A/S	15-Apr-2025	10:48:23 AM	54	1296.00	XCSE

Exhibit 99.1(a)

APPENDIX Share buy-back programme - Specification for April 14 – April 18, 2025

GENMAB A/S	15-Apr-2025	10:48:23 AM	35	1296.50	XCSE
GENMAB A/S	15-Apr-2025	10:48:23 AM	15	1296.50	XCSE
GENMAB A/S	15-Apr-2025	10:48:23 AM	10	1296.50	XCSE
GENMAB A/S	15-Apr-2025	10:48:23 AM	10	1295.50	TQEX
GENMAB A/S	15-Apr-2025	10:48:23 AM	36	1296.50	CEUX
GENMAB A/S	15-Apr-2025	10:48:23 AM	68	1296.00	CEUX
GENMAB A/S	15-Apr-2025	10:48:23 AM	1	1296.00	CEUX
GENMAB A/S	15-Apr-2025	10:48:23 AM	23	1295.50	AQEU
GENMAB A/S	15-Apr-2025	10:48:29 AM	88	1295.50	XCSE
GENMAB A/S	15-Apr-2025	10:48:48 AM	87	1294.00	XCSE
GENMAB A/S	15-Apr-2025	10:48:48 AM	85	1293.50	XCSE
GENMAB A/S	15-Apr-2025	10:48:48 AM	90	1294.50	CEUX
GENMAB A/S	15-Apr-2025	10:48:48 AM	15	1294.50	CEUX
GENMAB A/S	15-Apr-2025	10:48:48 AM	76	1294.50	CEUX
GENMAB A/S	15-Apr-2025	10:48:48 AM	85	1293.50	CEUX
GENMAB A/S	15-Apr-2025	10:49:28 AM	89	1292.50	XCSE
GENMAB A/S	15-Apr-2025	10:49:28 AM	87	1292.50	CEUX
GENMAB A/S	15-Apr-2025	10:51:03 AM	86	1293.50	XCSE
GENMAB A/S	15-Apr-2025	10:51:03 AM	35	1293.50	TQEX
GENMAB A/S	15-Apr-2025	10:51:03 AM	79	1293.50	CEUX
GENMAB A/S	15-Apr-2025	10:51:03 AM	35	1294.00	AQEU
GENMAB A/S	15-Apr-2025	10:53:27 AM	72	1294.50	CEUX
GENMAB A/S	15-Apr-2025	10:54:33 AM	43	1294.50	XCSE
GENMAB A/S	15-Apr-2025	10:57:19 AM	29	1295.00	TQEX
GENMAB A/S	15-Apr-2025	10:57:51 AM	64	1294.00	XCSE
GENMAB A/S	15-Apr-2025	10:58:00 AM	30	1295.50	XCSE
GENMAB A/S	15-Apr-2025	10:58:00 AM	14	1295.50	XCSE
GENMAB A/S	15-Apr-2025	10:58:00 AM	14	1295.50	XCSE
GENMAB A/S	15-Apr-2025	10:58:00 AM	34	1295.50	XCSE
GENMAB A/S	15-Apr-2025	10:58:00 AM	15	1295.50	XCSE
GENMAB A/S	15-Apr-2025	10:58:01 AM	15	1295.50	XCSE
GENMAB A/S	15-Apr-2025	10:58:01 AM	15	1295.50	XCSE
GENMAB A/S	15-Apr-2025	10:59:47 AM	7	1297.00	XCSE
GENMAB A/S	15-Apr-2025	10:59:47 AM	14	1297.00	XCSE
GENMAB A/S	15-Apr-2025	10:59:47 AM	93	1297.00	XCSE
GENMAB A/S	15-Apr-2025	11:00:00 AM	35	1297.00	XCSE
GENMAB A/S	15-Apr-2025	11:00:00 AM	14	1297.00	XCSE
GENMAB A/S	15-Apr-2025	11:00:00 AM	15	1297.00	XCSE
GENMAB A/S	15-Apr-2025	11:00:00 AM	50	1297.00	XCSE
GENMAB A/S	15-Apr-2025	11:00:53 AM	30	1297.00	XCSE
GENMAB A/S	15-Apr-2025	11:00:53 AM	15	1297.00	XCSE
GENMAB A/S	15-Apr-2025	11:02:01 AM	42	1297.00	XCSE
GENMAB A/S	15-Apr-2025	11:02:01 AM	69	1297.00	XCSE

Exhibit 99.1(a)

APPENDIX Share buy-back programme - Specification for April 14 – April 18, 2025

GENMAB A/S	15-Apr-2025	11:02:01 AM	25	1297.00	XCSE
GENMAB A/S	15-Apr-2025	11:02:01 AM	24	1297.00	XCSE
GENMAB A/S	15-Apr-2025	11:02:01 AM	42	1297.00	XCSE
GENMAB A/S	15-Apr-2025	11:02:01 AM	27	1297.00	TQEX
GENMAB A/S	15-Apr-2025	11:02:06 AM	32	1296.50	AQEU
GENMAB A/S	15-Apr-2025	11:02:06 AM	3	1296.50	AQEU
GENMAB A/S	15-Apr-2025	11:02:06 AM	87	1296.50	CEUX
GENMAB A/S	15-Apr-2025	11:02:36 AM	71	1296.00	XCSE
GENMAB A/S	15-Apr-2025	11:02:36 AM	18	1296.00	XCSE
GENMAB A/S	15-Apr-2025	11:02:36 AM	26	1296.00	TQEX
GENMAB A/S	15-Apr-2025	11:05:11 AM	84	1296.00	XCSE
GENMAB A/S	15-Apr-2025	11:06:05 AM	13	1297.00	XCSE
GENMAB A/S	15-Apr-2025	11:06:05 AM	42	1297.00	XCSE
GENMAB A/S	15-Apr-2025	11:06:05 AM	4	1297.00	XCSE
GENMAB A/S	15-Apr-2025	11:06:05 AM	36	1297.00	CEUX
GENMAB A/S	15-Apr-2025	11:06:15 AM	90	1297.00	XCSE
GENMAB A/S	15-Apr-2025	11:06:15 AM	90	1297.50	XCSE
GENMAB A/S	15-Apr-2025	11:06:15 AM	85	1298.00	CEUX
GENMAB A/S	15-Apr-2025	11:07:13 AM	25	1298.00	CEUX
GENMAB A/S	15-Apr-2025	11:09:04 AM	62	1298.00	XCSE
GENMAB A/S	15-Apr-2025	11:09:23 AM	28	1298.50	XCSE
GENMAB A/S	15-Apr-2025	11:10:39 AM	91	1299.50	XCSE
GENMAB A/S	15-Apr-2025	11:10:39 AM	14	1299.50	XCSE
GENMAB A/S	15-Apr-2025	11:13:10 AM	89	1299.50	XCSE
GENMAB A/S	15-Apr-2025	11:13:10 AM	34	1299.50	TQEX
GENMAB A/S	15-Apr-2025	11:13:10 AM	88	1299.50	CEUX
GENMAB A/S	15-Apr-2025	11:13:30 AM	72	1299.50	XCSE
GENMAB A/S	15-Apr-2025	11:13:30 AM	22	1299.00	AQEU
GENMAB A/S	15-Apr-2025	11:14:25 AM	91	1302.00	XCSE
GENMAB A/S	15-Apr-2025	11:14:25 AM	30	1302.00	CEUX
GENMAB A/S	15-Apr-2025	11:14:25 AM	54	1301.50	CEUX
GENMAB A/S	15-Apr-2025	11:14:26 AM	45	1302.00	XCSE
GENMAB A/S	15-Apr-2025	11:15:00 AM	25	1302.50	TQEX
GENMAB A/S	15-Apr-2025	11:15:00 AM	89	1302.50	CEUX
GENMAB A/S	15-Apr-2025	11:15:00 AM	15	1302.50	CEUX
GENMAB A/S	15-Apr-2025	11:15:02 AM	57	1302.50	XCSE
GENMAB A/S	15-Apr-2025	11:15:07 AM	23	1302.50	AQEU
GENMAB A/S	15-Apr-2025	11:15:07 AM	20	1302.50	CEUX
GENMAB A/S	15-Apr-2025	11:15:33 AM	25	1303.00	XCSE
GENMAB A/S	15-Apr-2025	11:15:33 AM	77	1303.00	XCSE
GENMAB A/S	15-Apr-2025	11:16:06 AM	84	1303.00	XCSE
GENMAB A/S	15-Apr-2025	11:16:06 AM	34	1302.50	TQEX
GENMAB A/S	15-Apr-2025	11:16:06 AM	21	1303.00	CEUX

Exhibit 99.1(a)

APPENDIX Share buy-back programme - Specification for April 14 – April 18, 2025

GENMAB A/S	15-Apr-2025	11:16:06 AM	69	1303.00	CEUX
GENMAB A/S	15-Apr-2025	11:17:04 AM	21	1302.50	AQEU
GENMAB A/S	15-Apr-2025	11:17:28 AM	8	1302.50	AQEU
GENMAB A/S	15-Apr-2025	11:18:52 AM	42	1303.00	CEUX
GENMAB A/S	15-Apr-2025	11:19:00 AM	44	1303.00	CEUX
GENMAB A/S	15-Apr-2025	11:19:03 AM	6	1302.50	AQEU
GENMAB A/S	15-Apr-2025	11:19:40 AM	85	1303.00	XCSE
GENMAB A/S	15-Apr-2025	11:19:40 AM	88	1303.00	CEUX
GENMAB A/S	15-Apr-2025	11:20:31 AM	29	1303.00	XCSE
GENMAB A/S	15-Apr-2025	11:20:31 AM	31	1303.00	TQEX
GENMAB A/S	15-Apr-2025	11:20:51 AM	60	1303.00	XCSE
GENMAB A/S	15-Apr-2025	11:20:51 AM	26	1303.00	XCSE
GENMAB A/S	15-Apr-2025	11:21:01 AM	58	1303.00	XCSE
GENMAB A/S	15-Apr-2025	11:21:01 AM	15	1303.00	XCSE
GENMAB A/S	15-Apr-2025	11:21:01 AM	24	1303.00	XCSE
GENMAB A/S	15-Apr-2025	11:21:01 AM	18	1303.00	CEUX
GENMAB A/S	15-Apr-2025	11:21:01 AM	7	1303.00	CEUX
GENMAB A/S	15-Apr-2025	11:21:09 AM	22	1302.50	AQEU
GENMAB A/S	15-Apr-2025	11:21:27 AM	84	1302.00	XCSE
GENMAB A/S	15-Apr-2025	11:21:27 AM	7	1302.50	AQEU
GENMAB A/S	15-Apr-2025	11:21:27 AM	10	1302.00	CEUX
GENMAB A/S	15-Apr-2025	11:21:33 AM	25	1302.00	CEUX
GENMAB A/S	15-Apr-2025	11:21:33 AM	12	1302.00	CEUX
GENMAB A/S	15-Apr-2025	11:21:33 AM	3	1302.00	CEUX
GENMAB A/S	15-Apr-2025	11:21:35 AM	26	1301.50	AQEU
GENMAB A/S	15-Apr-2025	11:21:49 AM	33	1301.00	XCSE
GENMAB A/S	15-Apr-2025	11:21:49 AM	22	1301.50	AQEU
GENMAB A/S	15-Apr-2025	11:21:49 AM	28	1301.50	TQEX
GENMAB A/S	15-Apr-2025	11:21:49 AM	1	1301.50	CEUX
GENMAB A/S	15-Apr-2025	11:21:49 AM	33	1301.50	CEUX
GENMAB A/S	15-Apr-2025	11:22:04 AM	58	1301.00	XCSE
GENMAB A/S	15-Apr-2025	11:24:51 AM	54	1301.50	XCSE
GENMAB A/S	15-Apr-2025	11:24:51 AM	16	1301.50	XCSE
GENMAB A/S	15-Apr-2025	11:24:51 AM	8	1301.00	CEUX
GENMAB A/S	15-Apr-2025	11:24:52 AM	46	1301.50	XCSE
GENMAB A/S	15-Apr-2025	11:26:26 AM	5	1302.50	CEUX
GENMAB A/S	15-Apr-2025	11:26:42 AM	46	1303.00	XCSE
GENMAB A/S	15-Apr-2025	11:30:11 AM	68	1304.00	XCSE
GENMAB A/S	15-Apr-2025	11:30:11 AM	20	1304.00	XCSE
GENMAB A/S	15-Apr-2025	11:30:11 AM	25	1304.00	TQEX
GENMAB A/S	15-Apr-2025	11:31:18 AM	13	1306.00	XCSE
GENMAB A/S	15-Apr-2025	11:31:18 AM	52	1306.00	XCSE
GENMAB A/S	15-Apr-2025	11:31:18 AM	49	1306.00	XCSE

Exhibit 99.1(a)

APPENDIX Share buy-back programme - Specification for April 14 – April 18, 2025

GENMAB A/S	15-Apr-2025	11:31:18 AM	8	1305.50	AQEU
GENMAB A/S	15-Apr-2025	11:31:18 AM	87	1305.50	CEUX
GENMAB A/S	15-Apr-2025	11:31:18 AM	36	1306.00	CEUX
GENMAB A/S	15-Apr-2025	11:31:18 AM	7	1306.00	CEUX
GENMAB A/S	15-Apr-2025	11:31:18 AM	8	1306.00	CEUX
GENMAB A/S	15-Apr-2025	11:31:18 AM	1	1306.00	CEUX
GENMAB A/S	15-Apr-2025	11:31:18 AM	25	1306.00	CEUX
GENMAB A/S	15-Apr-2025	11:33:04 AM	25	1306.50	TQEX
GENMAB A/S	15-Apr-2025	11:33:11 AM	84	1306.50	CEUX
GENMAB A/S	15-Apr-2025	11:34:01 AM	77	1306.00	XCSE
GENMAB A/S	15-Apr-2025	11:34:01 AM	9	1306.00	XCSE
GENMAB A/S	15-Apr-2025	11:34:01 AM	48	1306.00	XCSE
GENMAB A/S	15-Apr-2025	11:34:01 AM	66	1306.00	XCSE
GENMAB A/S	15-Apr-2025	11:34:01 AM	98	1306.00	XCSE
GENMAB A/S	15-Apr-2025	11:34:01 AM	15	1306.00	CEUX
GENMAB A/S	15-Apr-2025	11:34:13 AM	47	1306.00	XCSE
GENMAB A/S	15-Apr-2025	11:34:13 AM	26	1306.00	XCSE
GENMAB A/S	15-Apr-2025	11:36:02 AM	91	1306.50	CEUX
GENMAB A/S	15-Apr-2025	11:36:04 AM	88	1306.00	XCSE
GENMAB A/S	15-Apr-2025	11:36:04 AM	25	1306.00	CEUX
GENMAB A/S	15-Apr-2025	11:36:04 AM	36	1306.50	CEUX
GENMAB A/S	15-Apr-2025	11:36:04 AM	25	1306.50	CEUX
GENMAB A/S	15-Apr-2025	11:36:04 AM	6	1306.50	CEUX
GENMAB A/S	15-Apr-2025	11:36:08 AM	13	1306.00	XCSE
GENMAB A/S	15-Apr-2025	11:36:15 AM	36	1306.00	CEUX
GENMAB A/S	15-Apr-2025	11:36:51 AM	84	1306.00	XCSE
GENMAB A/S	15-Apr-2025	11:37:00 AM	1	1306.00	XCSE
GENMAB A/S	15-Apr-2025	11:37:04 AM	21	1305.50	AQEU
GENMAB A/S	15-Apr-2025	11:37:05 AM	16	1306.00	XCSE
GENMAB A/S	15-Apr-2025	11:37:05 AM	30	1306.00	XCSE
GENMAB A/S	15-Apr-2025	11:37:05 AM	14	1306.00	XCSE
GENMAB A/S	15-Apr-2025	11:37:05 AM	36	1306.00	CEUX
GENMAB A/S	15-Apr-2025	11:37:21 AM	10	1306.00	XCSE
GENMAB A/S	15-Apr-2025	11:37:21 AM	25	1306.00	XCSE
GENMAB A/S	15-Apr-2025	11:38:06 AM	29	1306.50	XCSE
GENMAB A/S	15-Apr-2025	11:38:12 AM	1	1306.50	XCSE
GENMAB A/S	15-Apr-2025	11:38:23 AM	14	1306.50	XCSE
GENMAB A/S	15-Apr-2025	11:39:00 AM	52	1306.50	XCSE
GENMAB A/S	15-Apr-2025	11:40:00 AM	23	1306.50	AQEU
GENMAB A/S	15-Apr-2025	11:40:00 AM	36	1307.00	CEUX
GENMAB A/S	15-Apr-2025	11:40:00 AM	36	1307.00	CEUX
GENMAB A/S	15-Apr-2025	11:40:00 AM	8	1307.00	CEUX
GENMAB A/S	15-Apr-2025	11:40:01 AM	32	1307.00	CEUX

Exhibit 99.1(a)

APPENDIX Share buy-back programme - Specification for April 14 – April 18, 2025

GENMAB A/S	15-Apr-2025	11:40:37 AM	32	1307.00	CEUX
GENMAB A/S	15-Apr-2025	11:40:41 AM	24	1306.50	AQEU
GENMAB A/S	15-Apr-2025	11:41:04 AM	47	1306.50	XCSE
GENMAB A/S	15-Apr-2025	11:41:04 AM	30	1306.50	XCSE
GENMAB A/S	15-Apr-2025	11:41:04 AM	25	1306.50	XCSE
GENMAB A/S	15-Apr-2025	11:41:04 AM	12	1306.50	XCSE
GENMAB A/S	15-Apr-2025	11:41:04 AM	6	1306.50	AQEU
GENMAB A/S	15-Apr-2025	11:41:04 AM	88	1306.50	CEUX
GENMAB A/S	15-Apr-2025	11:41:05 AM	47	1306.50	XCSE
GENMAB A/S	15-Apr-2025	11:41:08 AM	89	1306.00	XCSE
GENMAB A/S	15-Apr-2025	11:42:06 AM	26	1305.50	TQEX
GENMAB A/S	15-Apr-2025	11:42:06 AM	12	1305.50	AQEU
GENMAB A/S	15-Apr-2025	11:42:06 AM	21	1305.50	CEUX
GENMAB A/S	15-Apr-2025	11:42:06 AM	65	1305.50	CEUX
GENMAB A/S	15-Apr-2025	11:42:41 AM	75	1305.00	XCSE
GENMAB A/S	15-Apr-2025	11:42:52 AM	10	1305.00	XCSE
GENMAB A/S	15-Apr-2025	11:44:23 AM	31	1305.50	XCSE
GENMAB A/S	15-Apr-2025	11:45:35 AM	58	1305.50	XCSE
GENMAB A/S	15-Apr-2025	11:45:35 AM	49	1305.50	XCSE
GENMAB A/S	15-Apr-2025	11:46:21 AM	86	1305.00	XCSE
GENMAB A/S	15-Apr-2025	11:47:32 AM	31	1305.50	XCSE
GENMAB A/S	15-Apr-2025	11:47:32 AM	21	1305.50	AQEU
GENMAB A/S	15-Apr-2025	11:48:34 AM	60	1305.50	XCSE
GENMAB A/S	15-Apr-2025	11:48:34 AM	24	1305.50	CEUX
GENMAB A/S	15-Apr-2025	11:51:22 AM	89	1305.00	XCSE
GENMAB A/S	15-Apr-2025	11:51:22 AM	72	1305.50	XCSE
GENMAB A/S	15-Apr-2025	11:51:22 AM	13	1305.50	XCSE
GENMAB A/S	15-Apr-2025	11:51:22 AM	16	1305.50	XCSE
GENMAB A/S	15-Apr-2025	11:51:22 AM	13	1305.50	XCSE
GENMAB A/S	15-Apr-2025	11:51:22 AM	33	1305.50	TQEX
GENMAB A/S	15-Apr-2025	11:51:22 AM	18	1305.50	AQEU
GENMAB A/S	15-Apr-2025	11:51:22 AM	36	1306.00	CEUX
GENMAB A/S	15-Apr-2025	11:51:22 AM	60	1305.50	CEUX
GENMAB A/S	15-Apr-2025	11:51:22 AM	36	1305.50	CEUX
GENMAB A/S	15-Apr-2025	11:51:22 AM	10	1305.50	CEUX
GENMAB A/S	15-Apr-2025	11:51:22 AM	26	1305.50	CEUX
GENMAB A/S	15-Apr-2025	11:51:22 AM	8	1305.50	CEUX
GENMAB A/S	15-Apr-2025	11:52:25 AM	88	1306.00	CEUX
GENMAB A/S	15-Apr-2025	11:54:07 AM	35	1306.50	TQEX
GENMAB A/S	15-Apr-2025	11:54:07 AM	22	1306.50	AQEU
GENMAB A/S	15-Apr-2025	11:54:07 AM	36	1306.50	CEUX
GENMAB A/S	15-Apr-2025	11:54:07 AM	23	1306.50	CEUX
GENMAB A/S	15-Apr-2025	11:54:30 AM	1	1306.50	CEUX

Exhibit 99.1(a)

APPENDIX Share buy-back programme - Specification for April 14 – April 18, 2025

GENMAB A/S	15-Apr-2025	11:55:38 AM	86	1307.00	XCSE
GENMAB A/S	15-Apr-2025	11:55:38 AM	35	1307.00	XCSE
GENMAB A/S	15-Apr-2025	11:55:38 AM	14	1307.00	XCSE
GENMAB A/S	15-Apr-2025	11:55:38 AM	35	1307.00	XCSE
GENMAB A/S	15-Apr-2025	11:55:38 AM	24	1307.00	XCSE
GENMAB A/S	15-Apr-2025	11:56:11 AM	86	1307.00	XCSE
GENMAB A/S	15-Apr-2025	11:57:10 AM	89	1307.50	XCSE
GENMAB A/S	15-Apr-2025	11:57:10 AM	36	1307.50	CEUX
GENMAB A/S	15-Apr-2025	11:57:33 AM	67	1307.50	XCSE
GENMAB A/S	15-Apr-2025	11:58:29 AM	36	1307.50	CEUX
GENMAB A/S	15-Apr-2025	11:58:30 AM	32	1307.50	CEUX
GENMAB A/S	15-Apr-2025	11:58:33 AM	56	1307.50	XCSE
GENMAB A/S	15-Apr-2025	11:59:00 AM	38	1307.00	TQEX
GENMAB A/S	15-Apr-2025	11:59:03 AM	23	1306.50	AQEU
GENMAB A/S	15-Apr-2025	11:59:03 AM	4	1306.50	CEUX
GENMAB A/S	15-Apr-2025	11:59:03 AM	24	1306.50	CEUX
GENMAB A/S	15-Apr-2025	11:59:16 AM	82	1306.00	XCSE
GENMAB A/S	15-Apr-2025	11:59:17 AM	4	1306.00	XCSE
GENMAB A/S	15-Apr-2025	11:59:32 AM	90	1305.00	XCSE
GENMAB A/S	15-Apr-2025	11:59:32 AM	32	1305.50	TQEX
GENMAB A/S	15-Apr-2025	11:59:32 AM	44	1305.50	AQEU
GENMAB A/S	15-Apr-2025	11:59:32 AM	87	1305.50	CEUX
GENMAB A/S	15-Apr-2025	11:59:33 AM	5	1304.50	AQEU
GENMAB A/S	15-Apr-2025	11:59:49 AM	37	1304.50	AQEU
GENMAB A/S	15-Apr-2025	11:59:49 AM	84	1304.50	CEUX
GENMAB A/S	15-Apr-2025	11:59:49 AM	2	1304.50	CEUX
GENMAB A/S	15-Apr-2025	12:03:19 PM	85	1304.50	XCSE
GENMAB A/S	15-Apr-2025	12:03:42 PM	38	1304.50	XCSE
GENMAB A/S	15-Apr-2025	12:03:42 PM	15	1304.50	XCSE
GENMAB A/S	15-Apr-2025	12:03:42 PM	14	1304.50	XCSE
GENMAB A/S	15-Apr-2025	12:03:42 PM	14	1304.50	XCSE
GENMAB A/S	15-Apr-2025	12:04:33 PM	15	1304.50	XCSE
GENMAB A/S	15-Apr-2025	12:04:33 PM	48	1304.50	XCSE
GENMAB A/S	15-Apr-2025	12:05:21 PM	87	1303.50	XCSE
GENMAB A/S	15-Apr-2025	12:05:21 PM	25	1304.00	AQEU
GENMAB A/S	15-Apr-2025	12:06:45 PM	84	1304.00	XCSE
GENMAB A/S	15-Apr-2025	12:06:46 PM	25	1304.00	TQEX
GENMAB A/S	15-Apr-2025	12:09:41 PM	87	1304.00	XCSE
GENMAB A/S	15-Apr-2025	12:09:41 PM	1	1304.50	CEUX
GENMAB A/S	15-Apr-2025	12:09:41 PM	25	1304.50	CEUX
GENMAB A/S	15-Apr-2025	12:10:14 PM	85	1304.50	CEUX
GENMAB A/S	15-Apr-2025	12:10:16 PM	24	1304.50	XCSE
GENMAB A/S	15-Apr-2025	12:10:16 PM	26	1304.50	XCSE

Exhibit 99.1(a)

APPENDIX Share buy-back programme - Specification for April 14 – April 18, 2025

GENMAB A/S	15-Apr-2025	12:10:16 PM	88	1304.00	XCSE
GENMAB A/S	15-Apr-2025	12:10:16 PM	25	1304.00	AQEU
GENMAB A/S	15-Apr-2025	12:10:16 PM	36	1304.50	CEUX
GENMAB A/S	15-Apr-2025	12:10:16 PM	3	1304.50	CEUX
GENMAB A/S	15-Apr-2025	12:10:17 PM	27	1304.00	TQEX
GENMAB A/S	15-Apr-2025	12:10:17 PM	32	1304.00	CEUX
GENMAB A/S	15-Apr-2025	12:12:47 PM	36	1304.00	CEUX
GENMAB A/S	15-Apr-2025	12:12:47 PM	11	1304.00	CEUX
GENMAB A/S	15-Apr-2025	12:13:22 PM	45	1304.50	XCSE
GENMAB A/S	15-Apr-2025	12:13:22 PM	15	1304.50	XCSE
GENMAB A/S	15-Apr-2025	12:13:22 PM	34	1304.50	XCSE
GENMAB A/S	15-Apr-2025	12:13:23 PM	16	1304.50	XCSE
GENMAB A/S	15-Apr-2025	12:13:23 PM	14	1304.50	XCSE
GENMAB A/S	15-Apr-2025	12:13:23 PM	39	1304.50	XCSE
GENMAB A/S	15-Apr-2025	12:13:23 PM	34	1304.50	XCSE
GENMAB A/S	15-Apr-2025	12:14:00 PM	86	1304.00	XCSE
GENMAB A/S	15-Apr-2025	12:14:00 PM	36	1304.00	CEUX
GENMAB A/S	15-Apr-2025	12:14:00 PM	3	1304.00	CEUX
GENMAB A/S	15-Apr-2025	12:14:00 PM	22	1303.50	CEUX
GENMAB A/S	15-Apr-2025	12:14:01 PM	66	1303.50	CEUX
GENMAB A/S	15-Apr-2025	12:15:21 PM	90	1302.50	XCSE
GENMAB A/S	15-Apr-2025	12:15:21 PM	32	1302.50	TQEX
GENMAB A/S	15-Apr-2025	12:15:21 PM	31	1303.00	AQEU
GENMAB A/S	15-Apr-2025	12:15:33 PM	25	1302.50	CEUX
GENMAB A/S	15-Apr-2025	12:15:33 PM	4	1302.50	CEUX
GENMAB A/S	15-Apr-2025	12:15:59 PM	84	1302.00	CEUX
GENMAB A/S	15-Apr-2025	12:17:42 PM	78	1302.50	CEUX
GENMAB A/S	15-Apr-2025	12:17:42 PM	12	1302.50	CEUX
GENMAB A/S	15-Apr-2025	12:17:51 PM	28	1302.50	XCSE
GENMAB A/S	15-Apr-2025	12:17:51 PM	14	1302.50	XCSE
GENMAB A/S	15-Apr-2025	12:19:53 PM	22	1302.00	AQEU
GENMAB A/S	15-Apr-2025	12:20:01 PM	39	1316.00	XCSE
GENMAB A/S	15-Apr-2025	12:20:01 PM	52	1316.00	XCSE
GENMAB A/S	15-Apr-2025	12:20:02 PM	84	1324.00	XCSE
GENMAB A/S	15-Apr-2025	12:20:02 PM	84	1323.00	XCSE
GENMAB A/S	15-Apr-2025	12:20:02 PM	14	1322.00	XCSE
GENMAB A/S	15-Apr-2025	12:20:02 PM	73	1322.00	XCSE
GENMAB A/S	15-Apr-2025	12:20:02 PM	85	1320.50	XCSE
GENMAB A/S	15-Apr-2025	12:20:02 PM	27	1325.00	TQEX
GENMAB A/S	15-Apr-2025	12:20:02 PM	28	1323.50	TQEX
GENMAB A/S	15-Apr-2025	12:20:02 PM	25	1325.00	AQEU
GENMAB A/S	15-Apr-2025	12:20:02 PM	27	1323.50	AQEU
GENMAB A/S	15-Apr-2025	12:20:02 PM	85	1324.50	CEUX

Exhibit 99.1(a)

APPENDIX Share buy-back programme - Specification for April 14 – April 18, 2025

GENMAB A/S	15-Apr-2025	12:20:02 PM	4	1323.50	CEUX
GENMAB A/S	15-Apr-2025	12:20:02 PM	83	1323.50	CEUX
GENMAB A/S	15-Apr-2025	12:20:02 PM	69	1322.50	CEUX
GENMAB A/S	15-Apr-2025	12:20:02 PM	20	1322.50	CEUX
GENMAB A/S	15-Apr-2025	12:20:02 PM	89	1321.00	CEUX
GENMAB A/S	15-Apr-2025	12:20:03 PM	85	1319.50	XCSE
GENMAB A/S	15-Apr-2025	12:20:03 PM	30	1321.00	XCSE
GENMAB A/S	15-Apr-2025	12:20:03 PM	20	1321.00	XCSE
GENMAB A/S	15-Apr-2025	12:20:03 PM	50	1320.00	XCSE
GENMAB A/S	15-Apr-2025	12:20:03 PM	27	1319.50	XCSE
GENMAB A/S	15-Apr-2025	12:20:03 PM	38	1321.50	CEUX
GENMAB A/S	15-Apr-2025	12:20:03 PM	35	1320.00	CEUX
GENMAB A/S	15-Apr-2025	12:20:35 PM	26	1311.00	XCSE
GENMAB A/S	15-Apr-2025	12:20:35 PM	33	1311.00	CEUX
GENMAB A/S	15-Apr-2025	12:21:14 PM	31	1310.00	XCSE
GENMAB A/S	15-Apr-2025	12:21:14 PM	26	1309.00	XCSE
GENMAB A/S	15-Apr-2025	12:21:54 PM	29	1309.00	XCSE
GENMAB A/S	15-Apr-2025	12:21:54 PM	22	1309.50	CEUX
GENMAB A/S	15-Apr-2025	12:21:54 PM	8	1309.50	CEUX
GENMAB A/S	15-Apr-2025	12:21:54 PM	2	1309.50	CEUX
GENMAB A/S	15-Apr-2025	12:22:10 PM	28	1311.50	CEUX
GENMAB A/S	15-Apr-2025	12:22:10 PM	2	1311.50	CEUX
GENMAB A/S	15-Apr-2025	12:22:16 PM	25	1314.50	XCSE
GENMAB A/S	15-Apr-2025	12:22:42 PM	25	1316.00	XCSE
GENMAB A/S	15-Apr-2025	12:22:49 PM	25	1314.50	XCSE
GENMAB A/S	15-Apr-2025	12:23:36 PM	25	1313.00	CEUX
GENMAB A/S	15-Apr-2025	12:23:36 PM	1	1313.00	CEUX
GENMAB A/S	15-Apr-2025	12:23:49 PM	6	1313.00	XCSE
GENMAB A/S	15-Apr-2025	12:23:49 PM	1	1313.00	XCSE
GENMAB A/S	15-Apr-2025	12:23:49 PM	1	1313.00	XCSE
GENMAB A/S	15-Apr-2025	12:23:49 PM	18	1313.00	XCSE
GENMAB A/S	15-Apr-2025	12:24:04 PM	25	1316.00	CEUX
GENMAB A/S	15-Apr-2025	12:24:05 PM	32	1316.50	XCSE
GENMAB A/S	15-Apr-2025	12:24:05 PM	27	1315.50	XCSE
GENMAB A/S	15-Apr-2025	12:24:05 PM	26	1316.00	AQEU
GENMAB A/S	15-Apr-2025	12:25:03 PM	29	1314.50	XCSE
GENMAB A/S	15-Apr-2025	12:25:03 PM	32	1313.50	XCSE
GENMAB A/S	15-Apr-2025	12:25:03 PM	25	1315.00	TQEX
GENMAB A/S	15-Apr-2025	12:25:03 PM	26	1315.50	CEUX
GENMAB A/S	15-Apr-2025	12:25:26 PM	19	1312.00	CEUX
GENMAB A/S	15-Apr-2025	12:28:43 PM	50	1311.50	XCSE
GENMAB A/S	15-Apr-2025	12:28:43 PM	17	1311.50	XCSE
GENMAB A/S	15-Apr-2025	12:28:43 PM	26	1311.50	CEUX

Exhibit 99.1(a)

APPENDIX Share buy-back programme - Specification for April 14 – April 18, 2025

GENMAB A/S	15-Apr-2025	12:29:33 PM	21	1311.50	CEUX
GENMAB A/S	15-Apr-2025	12:29:37 PM	20	1311.50	CEUX
GENMAB A/S	15-Apr-2025	12:29:45 PM	25	1311.50	TQEX
GENMAB A/S	15-Apr-2025	12:30:53 PM	26	1311.50	AQEU
GENMAB A/S	15-Apr-2025	12:30:53 PM	11	1311.50	CEUX
GENMAB A/S	15-Apr-2025	12:30:53 PM	35	1311.50	CEUX
GENMAB A/S	15-Apr-2025	12:31:01 PM	82	1311.00	XCSE
GENMAB A/S	15-Apr-2025	12:31:02 PM	29	1310.00	XCSE
GENMAB A/S	15-Apr-2025	12:31:02 PM	29	1310.00	CEUX
GENMAB A/S	15-Apr-2025	12:31:45 PM	26	1309.00	XCSE
GENMAB A/S	15-Apr-2025	12:31:45 PM	30	1309.00	CEUX
GENMAB A/S	15-Apr-2025	12:31:53 PM	25	1308.00	CEUX
GENMAB A/S	15-Apr-2025	12:32:02 PM	17	1307.50	XCSE
GENMAB A/S	15-Apr-2025	12:32:02 PM	54	1307.50	XCSE
GENMAB A/S	15-Apr-2025	12:32:15 PM	4	1306.00	XCSE
GENMAB A/S	15-Apr-2025	12:32:15 PM	74	1306.00	XCSE
GENMAB A/S	15-Apr-2025	12:32:58 PM	24	1305.00	XCSE
GENMAB A/S	15-Apr-2025	12:32:59 PM	12	1305.00	XCSE
GENMAB A/S	15-Apr-2025	12:32:59 PM	25	1305.00	XCSE
GENMAB A/S	15-Apr-2025	12:33:04 PM	18	1304.50	CEUX
GENMAB A/S	15-Apr-2025	12:33:04 PM	8	1304.50	CEUX
GENMAB A/S	15-Apr-2025	12:33:17 PM	30	1304.00	XCSE
GENMAB A/S	15-Apr-2025	12:33:17 PM	15	1304.00	XCSE
GENMAB A/S	15-Apr-2025	12:35:39 PM	61	1305.00	XCSE
GENMAB A/S	15-Apr-2025	12:35:39 PM	30	1305.00	CEUX
GENMAB A/S	15-Apr-2025	12:35:39 PM	7	1305.00	CEUX
GENMAB A/S	15-Apr-2025	12:36:30 PM	17	1304.00	XCSE
GENMAB A/S	15-Apr-2025	12:36:30 PM	1	1304.00	XCSE
GENMAB A/S	15-Apr-2025	12:38:51 PM	11	1304.00	XCSE
GENMAB A/S	15-Apr-2025	12:40:09 PM	27	1303.00	XCSE
GENMAB A/S	15-Apr-2025	12:40:09 PM	25	1303.50	TQEX
GENMAB A/S	15-Apr-2025	12:40:09 PM	3	1302.50	AQEU
GENMAB A/S	15-Apr-2025	12:40:09 PM	25	1303.50	CEUX
GENMAB A/S	15-Apr-2025	12:40:09 PM	2	1302.50	CEUX
GENMAB A/S	15-Apr-2025	12:40:09 PM	23	1302.50	CEUX
GENMAB A/S	15-Apr-2025	12:40:23 PM	21	1303.50	AQEU
GENMAB A/S	15-Apr-2025	12:41:40 PM	30	1304.00	CEUX
GENMAB A/S	15-Apr-2025	12:41:40 PM	30	1304.00	CEUX
GENMAB A/S	15-Apr-2025	12:41:40 PM	3	1304.00	CEUX
GENMAB A/S	15-Apr-2025	12:41:54 PM	91	1304.00	XCSE
GENMAB A/S	15-Apr-2025	12:41:54 PM	25	1304.00	TQEX
GENMAB A/S	15-Apr-2025	12:41:54 PM	4	1303.50	AQEU
GENMAB A/S	15-Apr-2025	12:41:55 PM	38	1303.00	CEUX

Exhibit 99.1(a)

APPENDIX Share buy-back programme - Specification for April 14 – April 18, 2025

GENMAB A/S	15-Apr-2025	12:41:55 PM	24	1303.00	CEUX
GENMAB A/S	15-Apr-2025	12:42:28 PM	21	1302.50	AQEU
GENMAB A/S	15-Apr-2025	12:42:31 PM	87	1302.50	XCSE
GENMAB A/S	15-Apr-2025	12:42:31 PM	1	1302.50	AQEU
GENMAB A/S	15-Apr-2025	12:42:31 PM	58	1302.00	CEUX
GENMAB A/S	15-Apr-2025	12:42:31 PM	8	1302.00	CEUX
GENMAB A/S	15-Apr-2025	12:42:32 PM	31	1301.50	XCSE
GENMAB A/S	15-Apr-2025	12:42:32 PM	12	1301.50	XCSE
GENMAB A/S	15-Apr-2025	12:42:38 PM	25	1301.50	TQEX
GENMAB A/S	15-Apr-2025	12:43:46 PM	10	1300.00	XCSE
GENMAB A/S	15-Apr-2025	12:43:46 PM	21	1300.00	XCSE
GENMAB A/S	15-Apr-2025	12:43:46 PM	58	1300.00	XCSE
GENMAB A/S	15-Apr-2025	12:44:31 PM	17	1299.50	CEUX
GENMAB A/S	15-Apr-2025	12:44:41 PM	85	1299.00	XCSE
GENMAB A/S	15-Apr-2025	12:44:41 PM	8	1299.50	CEUX
GENMAB A/S	15-Apr-2025	12:44:41 PM	4	1298.50	CEUX
GENMAB A/S	15-Apr-2025	12:44:41 PM	4	1298.50	CEUX
GENMAB A/S	15-Apr-2025	12:44:41 PM	18	1298.50	CEUX
GENMAB A/S	15-Apr-2025	12:44:50 PM	15	1299.50	CEUX
GENMAB A/S	15-Apr-2025	12:44:57 PM	11	1299.50	CEUX
GENMAB A/S	15-Apr-2025	12:45:21 PM	65	1299.00	XCSE
GENMAB A/S	15-Apr-2025	12:45:22 PM	13	1298.50	CEUX
GENMAB A/S	15-Apr-2025	12:45:22 PM	13	1298.50	CEUX
GENMAB A/S	15-Apr-2025	12:46:35 PM	25	1300.00	AQEU
GENMAB A/S	15-Apr-2025	12:46:35 PM	25	1300.00	CEUX
GENMAB A/S	15-Apr-2025	12:46:55 PM	25	1300.00	CEUX
GENMAB A/S	15-Apr-2025	12:49:40 PM	16	1300.00	TQEX
GENMAB A/S	15-Apr-2025	12:49:40 PM	9	1300.00	TQEX
GENMAB A/S	15-Apr-2025	12:49:40 PM	14	1300.00	CEUX
GENMAB A/S	15-Apr-2025	12:49:40 PM	21	1300.00	CEUX
GENMAB A/S	15-Apr-2025	12:50:25 PM	81	1299.50	XCSE
GENMAB A/S	15-Apr-2025	12:50:27 PM	1	1299.00	CEUX
GENMAB A/S	15-Apr-2025	12:50:29 PM	18	1299.00	CEUX
GENMAB A/S	15-Apr-2025	12:50:29 PM	6	1299.00	CEUX
GENMAB A/S	15-Apr-2025	12:51:12 PM	40	1300.00	CEUX
GENMAB A/S	15-Apr-2025	12:51:18 PM	10	1300.00	AQEU
GENMAB A/S	15-Apr-2025	12:51:19 PM	15	1300.00	AQEU
GENMAB A/S	15-Apr-2025	12:51:20 PM	87	1300.50	XCSE
GENMAB A/S	15-Apr-2025	12:51:45 PM	35	1300.50	XCSE
GENMAB A/S	15-Apr-2025	12:51:45 PM	50	1300.50	XCSE
GENMAB A/S	15-Apr-2025	12:51:45 PM	27	1301.00	CEUX
GENMAB A/S	15-Apr-2025	12:53:07 PM	85	1300.50	XCSE
GENMAB A/S	15-Apr-2025	12:53:07 PM	25	1300.50	TQEX

Exhibit 99.1(a)

APPENDIX Share buy-back programme - Specification for April 14 – April 18, 2025

GENMAB A/S	15-Apr-2025	12:53:07 PM	25	1300.50	CEUX
GENMAB A/S	15-Apr-2025	12:55:22 PM	89	1299.50	XCSE
GENMAB A/S	15-Apr-2025	12:55:25 PM	10	1299.00	CEUX
GENMAB A/S	15-Apr-2025	12:55:25 PM	15	1299.00	CEUX
GENMAB A/S	15-Apr-2025	12:57:15 PM	25	1300.00	AQEU
GENMAB A/S	15-Apr-2025	12:58:01 PM	32	1299.50	XCSE
GENMAB A/S	15-Apr-2025	12:58:01 PM	57	1299.50	XCSE
GENMAB A/S	15-Apr-2025	12:58:01 PM	25	1299.50	TQEX
GENMAB A/S	15-Apr-2025	12:58:01 PM	26	1299.50	CEUX
GENMAB A/S	15-Apr-2025	12:58:01 PM	35	1299.50	CEUX
GENMAB A/S	15-Apr-2025	12:58:14 PM	86	1298.50	XCSE
GENMAB A/S	15-Apr-2025	12:58:15 PM	22	1298.00	CEUX
GENMAB A/S	15-Apr-2025	12:58:15 PM	6	1298.00	CEUX
GENMAB A/S	15-Apr-2025	12:58:38 PM	84	1298.00	XCSE
GENMAB A/S	15-Apr-2025	12:58:38 PM	39	1298.00	CEUX
GENMAB A/S	15-Apr-2025	12:58:41 PM	7	1298.00	CEUX
GENMAB A/S	15-Apr-2025	1:00:00 PM	90	1299.00	XCSE
GENMAB A/S	15-Apr-2025	1:00:00 PM	5	1298.50	AQEU
GENMAB A/S	15-Apr-2025	1:00:00 PM	18	1298.50	CEUX
GENMAB A/S	15-Apr-2025	1:00:00 PM	17	1298.50	CEUX
GENMAB A/S	15-Apr-2025	1:00:00 PM	8	1298.50	CEUX
GENMAB A/S	15-Apr-2025	1:00:02 PM	12	1298.50	AQEU
GENMAB A/S	15-Apr-2025	1:00:02 PM	8	1298.50	AQEU
GENMAB A/S	15-Apr-2025	1:01:05 PM	77	1299.00	XCSE
GENMAB A/S	15-Apr-2025	1:01:05 PM	14	1299.00	XCSE
GENMAB A/S	15-Apr-2025	1:01:05 PM	91	1298.00	XCSE
GENMAB A/S	15-Apr-2025	1:01:05 PM	25	1298.00	TQEX
GENMAB A/S	15-Apr-2025	1:01:05 PM	35	1299.50	CEUX
GENMAB A/S	15-Apr-2025	1:01:05 PM	29	1298.50	CEUX
GENMAB A/S	15-Apr-2025	1:01:06 PM	22	1298.00	XCSE
GENMAB A/S	15-Apr-2025	1:01:06 PM	29	1298.00	CEUX
GENMAB A/S	15-Apr-2025	1:01:08 PM	41	1298.00	XCSE
GENMAB A/S	15-Apr-2025	1:01:10 PM	64	1297.00	XCSE
GENMAB A/S	15-Apr-2025	1:01:10 PM	3	1297.00	XCSE
GENMAB A/S	15-Apr-2025	1:04:08 PM	10	1299.00	XCSE
GENMAB A/S	15-Apr-2025	1:04:08 PM	43	1299.00	XCSE
GENMAB A/S	15-Apr-2025	1:04:08 PM	32	1299.00	CEUX
GENMAB A/S	15-Apr-2025	1:04:15 PM	3	1299.00	XCSE
GENMAB A/S	15-Apr-2025	1:04:15 PM	17	1299.00	AQEU
GENMAB A/S	15-Apr-2025	1:04:15 PM	31	1299.00	CEUX
GENMAB A/S	15-Apr-2025	1:05:24 PM	5	1299.50	CEUX
GENMAB A/S	15-Apr-2025	1:05:27 PM	21	1299.00	XCSE
GENMAB A/S	15-Apr-2025	1:05:27 PM	37	1299.50	CEUX

Exhibit 99.1(a)

APPENDIX Share buy-back programme - Specification for April 14 – April 18, 2025

GENMAB A/S	15-Apr-2025	1:06:00 PM	45	1299.00	XCSE
GENMAB A/S	15-Apr-2025	1:06:00 PM	25	1299.50	TQEX
GENMAB A/S	15-Apr-2025	1:06:03 PM	8	1299.00	AQEU
GENMAB A/S	15-Apr-2025	1:08:51 PM	25	1298.50	TQEX
GENMAB A/S	15-Apr-2025	1:10:03 PM	90	1299.00	XCSE
GENMAB A/S	15-Apr-2025	1:10:03 PM	67	1299.00	CEUX
GENMAB A/S	15-Apr-2025	1:10:13 PM	18	1298.50	AQEU
GENMAB A/S	15-Apr-2025	1:10:13 PM	7	1298.50	AQEU
GENMAB A/S	15-Apr-2025	1:10:32 PM	45	1298.00	XCSE
GENMAB A/S	15-Apr-2025	1:10:32 PM	13	1298.00	CEUX
GENMAB A/S	15-Apr-2025	1:10:32 PM	19	1298.00	CEUX
GENMAB A/S	15-Apr-2025	1:11:06 PM	48	1298.50	CEUX
GENMAB A/S	15-Apr-2025	1:11:10 PM	2	1298.50	CEUX
GENMAB A/S	15-Apr-2025	1:11:39 PM	21	1298.00	XCSE
GENMAB A/S	15-Apr-2025	1:12:29 PM	13	1298.00	XCSE
GENMAB A/S	15-Apr-2025	1:12:29 PM	51	1298.00	XCSE
GENMAB A/S	15-Apr-2025	1:12:57 PM	43	1297.50	CEUX
GENMAB A/S	15-Apr-2025	1:13:31 PM	22	1297.00	XCSE
GENMAB A/S	15-Apr-2025	1:14:07 PM	16	1297.50	XCSE
GENMAB A/S	15-Apr-2025	1:14:07 PM	29	1297.50	XCSE
GENMAB A/S	15-Apr-2025	1:14:07 PM	16	1297.50	XCSE
GENMAB A/S	15-Apr-2025	1:14:25 PM	16	1296.50	CEUX
GENMAB A/S	15-Apr-2025	1:14:59 PM	14	1296.50	TQEX
GENMAB A/S	15-Apr-2025	1:14:59 PM	3	1296.50	AQEU
GENMAB A/S	15-Apr-2025	1:14:59 PM	9	1296.50	CEUX
GENMAB A/S	15-Apr-2025	1:15:09 PM	16	1297.00	XCSE
GENMAB A/S	15-Apr-2025	1:15:09 PM	5	1297.00	XCSE
GENMAB A/S	15-Apr-2025	1:15:09 PM	15	1297.00	XCSE
GENMAB A/S	15-Apr-2025	1:15:10 PM	18	1296.50	AQEU
GENMAB A/S	15-Apr-2025	1:15:31 PM	11	1296.50	TQEX
GENMAB A/S	15-Apr-2025	1:15:31 PM	4	1296.50	AQEU
GENMAB A/S	15-Apr-2025	1:16:24 PM	41	1296.50	XCSE
GENMAB A/S	15-Apr-2025	1:16:24 PM	45	1296.50	XCSE
GENMAB A/S	15-Apr-2025	1:16:24 PM	62	1296.50	CEUX
GENMAB A/S	15-Apr-2025	1:16:24 PM	2	1296.50	CEUX
GENMAB A/S	15-Apr-2025	1:16:39 PM	88	1295.50	XCSE
GENMAB A/S	15-Apr-2025	1:16:42 PM	37	1295.00	CEUX
GENMAB A/S	15-Apr-2025	1:16:45 PM	25	1294.50	AQEU
GENMAB A/S	15-Apr-2025	1:16:47 PM	14	1294.00	XCSE
GENMAB A/S	15-Apr-2025	1:16:47 PM	73	1294.00	XCSE
GENMAB A/S	15-Apr-2025	1:16:47 PM	46	1294.00	CEUX
GENMAB A/S	15-Apr-2025	1:17:41 PM	66	1293.00	XCSE
GENMAB A/S	15-Apr-2025	1:18:53 PM	11	1296.50	XCSE

Exhibit 99.1(a)

APPENDIX Share buy-back programme - Specification for April 14 – April 18, 2025

GENMAB A/S	15-Apr-2025	1:18:53 PM	74	1296.50	XCSE
GENMAB A/S	15-Apr-2025	1:18:53 PM	25	1296.50	TQEX
GENMAB A/S	15-Apr-2025	1:18:53 PM	18	1296.50	CEUX
GENMAB A/S	15-Apr-2025	1:18:53 PM	32	1296.50	CEUX
GENMAB A/S	15-Apr-2025	1:19:07 PM	89	1295.50	XCSE
GENMAB A/S	15-Apr-2025	1:19:07 PM	85	1294.00	XCSE
GENMAB A/S	15-Apr-2025	1:19:07 PM	47	1295.50	CEUX
GENMAB A/S	15-Apr-2025	1:19:07 PM	41	1294.00	CEUX
GENMAB A/S	15-Apr-2025	1:19:51 PM	49	1294.00	XCSE
GENMAB A/S	15-Apr-2025	1:21:52 PM	39	1295.00	CEUX
GENMAB A/S	15-Apr-2025	1:21:59 PM	19	1295.00	TQEX
GENMAB A/S	15-Apr-2025	1:21:59 PM	6	1295.00	TQEX
GENMAB A/S	15-Apr-2025	1:22:43 PM	21	1295.50	CEUX
GENMAB A/S	15-Apr-2025	1:22:43 PM	13	1295.50	CEUX
GENMAB A/S	15-Apr-2025	1:22:48 PM	14	1295.50	AQEU
GENMAB A/S	15-Apr-2025	1:23:19 PM	87	1296.00	XCSE
GENMAB A/S	15-Apr-2025	1:23:19 PM	33	1296.00	CEUX
GENMAB A/S	15-Apr-2025	1:23:21 PM	11	1295.50	AQEU
GENMAB A/S	15-Apr-2025	1:23:35 PM	68	1297.00	XCSE
GENMAB A/S	15-Apr-2025	1:23:36 PM	17	1297.00	XCSE
GENMAB A/S	15-Apr-2025	1:23:36 PM	15	1296.00	XCSE
GENMAB A/S	15-Apr-2025	1:23:36 PM	73	1296.00	XCSE
GENMAB A/S	15-Apr-2025	1:23:36 PM	31	1297.00	CEUX
GENMAB A/S	15-Apr-2025	1:23:52 PM	91	1295.00	XCSE
GENMAB A/S	15-Apr-2025	1:24:35 PM	27	1293.50	XCSE
GENMAB A/S	15-Apr-2025	1:24:35 PM	25	1292.50	XCSE
GENMAB A/S	15-Apr-2025	1:24:35 PM	25	1293.00	CEUX
GENMAB A/S	15-Apr-2025	1:25:43 PM	29	1292.50	CEUX
GENMAB A/S	15-Apr-2025	1:26:53 PM	66	1293.00	XCSE
GENMAB A/S	15-Apr-2025	1:27:45 PM	40	1293.00	XCSE
GENMAB A/S	15-Apr-2025	1:27:45 PM	25	1293.50	TQEX
GENMAB A/S	15-Apr-2025	1:27:45 PM	25	1293.50	AQEU
GENMAB A/S	15-Apr-2025	1:27:45 PM	25	1293.50	CEUX
GENMAB A/S	15-Apr-2025	1:28:07 PM	28	1292.50	CEUX
GENMAB A/S	15-Apr-2025	1:28:08 PM	26	1292.00	XCSE
GENMAB A/S	15-Apr-2025	1:28:13 PM	3	1292.00	XCSE
GENMAB A/S	15-Apr-2025	1:28:13 PM	32	1291.50	CEUX
GENMAB A/S	15-Apr-2025	1:28:37 PM	30	1291.00	XCSE
GENMAB A/S	15-Apr-2025	1:28:37 PM	28	1290.50	CEUX
GENMAB A/S	15-Apr-2025	1:28:39 PM	25	1290.50	XCSE
GENMAB A/S	15-Apr-2025	1:29:03 PM	37	1291.50	XCSE
GENMAB A/S	15-Apr-2025	1:31:02 PM	69	1292.50	XCSE
GENMAB A/S	15-Apr-2025	1:31:02 PM	36	1292.50	CEUX

Exhibit 99.1(a)

APPENDIX Share buy-back programme - Specification for April 14 – April 18, 2025

GENMAB A/S	15-Apr-2025	1:31:14 PM	12	1292.50	TQEX
GENMAB A/S	15-Apr-2025	1:31:14 PM	5	1292.50	TQEX
GENMAB A/S	15-Apr-2025	1:33:00 PM	84	1293.50	XCSE
GENMAB A/S	15-Apr-2025	1:33:00 PM	25	1293.50	TQEX
GENMAB A/S	15-Apr-2025	1:33:59 PM	2	1295.00	CEUX
GENMAB A/S	15-Apr-2025	1:37:07 PM	77	1295.50	XCSE
GENMAB A/S	15-Apr-2025	1:37:07 PM	9	1295.50	XCSE
GENMAB A/S	15-Apr-2025	1:37:07 PM	27	1295.50	TQEX
GENMAB A/S	15-Apr-2025	1:37:07 PM	34	1295.50	AQEU
GENMAB A/S	15-Apr-2025	1:37:30 PM	90	1295.50	XCSE
GENMAB A/S	15-Apr-2025	1:38:31 PM	45	1295.00	CEUX
GENMAB A/S	15-Apr-2025	1:39:45 PM	90	1295.50	XCSE
GENMAB A/S	15-Apr-2025	1:39:45 PM	53	1295.50	CEUX
GENMAB A/S	15-Apr-2025	1:39:55 PM	28	1296.00	AQEU
GENMAB A/S	15-Apr-2025	1:40:00 PM	17	1295.50	CEUX
GENMAB A/S	15-Apr-2025	1:40:26 PM	12	1295.50	CEUX
GENMAB A/S	15-Apr-2025	1:41:11 PM	4	1295.50	CEUX
GENMAB A/S	15-Apr-2025	1:41:21 PM	28	1295.00	AQEU
GENMAB A/S	15-Apr-2025	1:41:30 PM	51	1294.50	XCSE
GENMAB A/S	15-Apr-2025	1:41:30 PM	6	1294.50	XCSE
GENMAB A/S	15-Apr-2025	1:41:44 PM	25	1294.50	TQEX
GENMAB A/S	15-Apr-2025	1:43:51 PM	79	1294.50	XCSE
GENMAB A/S	15-Apr-2025	1:43:57 PM	9	1294.50	XCSE
GENMAB A/S	15-Apr-2025	1:46:07 PM	36	1294.50	XCSE
GENMAB A/S	15-Apr-2025	1:46:07 PM	20	1294.50	XCSE
GENMAB A/S	15-Apr-2025	1:46:07 PM	34	1294.50	XCSE
GENMAB A/S	15-Apr-2025	1:46:52 PM	36	1294.50	XCSE
GENMAB A/S	15-Apr-2025	1:46:52 PM	22	1294.50	XCSE
GENMAB A/S	15-Apr-2025	1:46:52 PM	42	1294.50	XCSE
GENMAB A/S	15-Apr-2025	1:47:33 PM	49	1294.50	XCSE
GENMAB A/S	15-Apr-2025	1:47:33 PM	35	1294.50	XCSE
GENMAB A/S	15-Apr-2025	1:47:33 PM	50	1294.50	XCSE
GENMAB A/S	15-Apr-2025	1:47:41 PM	27	1293.50	XCSE
GENMAB A/S	15-Apr-2025	1:47:41 PM	25	1294.00	TQEX
GENMAB A/S	15-Apr-2025	1:47:41 PM	26	1294.00	AQEU
GENMAB A/S	15-Apr-2025	1:47:41 PM	23	1293.00	AQEU
GENMAB A/S	15-Apr-2025	1:47:41 PM	42	1294.00	CEUX
GENMAB A/S	15-Apr-2025	1:47:55 PM	5	1293.00	CEUX
GENMAB A/S	15-Apr-2025	1:48:19 PM	30	1293.00	TQEX
GENMAB A/S	15-Apr-2025	1:48:19 PM	26	1293.00	CEUX
GENMAB A/S	15-Apr-2025	1:48:22 PM	84	1292.50	XCSE
GENMAB A/S	15-Apr-2025	1:48:24 PM	28	1292.00	CEUX
GENMAB A/S	15-Apr-2025	1:49:51 PM	89	1293.00	CEUX

100

Exhibit 99.1(a)

APPENDIX Share buy-back programme - Specification for April 14 – April 18, 2025

GENMAB A/S	15-Apr-2025	1:50:52 PM	50	1292.50	XCSE
GENMAB A/S	15-Apr-2025	1:50:52 PM	36	1292.50	XCSE
GENMAB A/S	15-Apr-2025	1:51:36 PM	84	1291.00	XCSE
GENMAB A/S	15-Apr-2025	1:51:36 PM	58	1292.00	CEUX
GENMAB A/S	15-Apr-2025	1:52:01 PM	26	1291.00	TQEX
GENMAB A/S	15-Apr-2025	1:52:02 PM	30	1291.00	AQEU
GENMAB A/S	15-Apr-2025	1:54:12 PM	35	1293.00	XCSE
GENMAB A/S	15-Apr-2025	1:54:12 PM	19	1293.00	XCSE
GENMAB A/S	15-Apr-2025	1:54:12 PM	25	1292.50	AQEU
GENMAB A/S	15-Apr-2025	1:54:12 PM	8	1293.00	CEUX
GENMAB A/S	15-Apr-2025	1:54:12 PM	8	1293.00	CEUX
GENMAB A/S	15-Apr-2025	1:55:01 PM	1	1294.00	CEUX
GENMAB A/S	15-Apr-2025	1:56:41 PM	43	1293.00	XCSE
GENMAB A/S	15-Apr-2025	1:56:41 PM	25	1293.50	TQEX
GENMAB A/S	15-Apr-2025	1:56:41 PM	91	1293.50	CEUX
GENMAB A/S	15-Apr-2025	1:57:22 PM	28	1294.00	XCSE
GENMAB A/S	15-Apr-2025	1:57:22 PM	28	1294.00	XCSE
GENMAB A/S	15-Apr-2025	1:58:08 PM	27	1294.00	XCSE
GENMAB A/S	15-Apr-2025	1:58:09 PM	27	1294.00	XCSE
GENMAB A/S	15-Apr-2025	1:58:09 PM	27	1294.00	XCSE
GENMAB A/S	15-Apr-2025	1:58:09 PM	27	1294.00	XCSE
GENMAB A/S	15-Apr-2025	1:58:51 PM	43	1293.00	XCSE
GENMAB A/S	15-Apr-2025	2:00:11 PM	5	1293.00	XCSE
GENMAB A/S	15-Apr-2025	2:01:30 PM	35	1293.00	XCSE
GENMAB A/S	15-Apr-2025	2:01:30 PM	17	1293.00	XCSE
GENMAB A/S	15-Apr-2025	2:01:30 PM	37	1293.00	XCSE
GENMAB A/S	15-Apr-2025	2:01:30 PM	25	1293.00	XCSE
GENMAB A/S	15-Apr-2025	2:01:30 PM	25	1292.50	TQEX
GENMAB A/S	15-Apr-2025	2:01:30 PM	25	1292.50	AQEU
GENMAB A/S	15-Apr-2025	2:01:30 PM	58	1292.50	CEUX
GENMAB A/S	15-Apr-2025	2:01:30 PM	33	1292.50	CEUX
GENMAB A/S	15-Apr-2025	2:01:30 PM	36	1292.50	CEUX
GENMAB A/S	15-Apr-2025	2:01:44 PM	114	1293.00	XCSE
GENMAB A/S	15-Apr-2025	2:01:44 PM	83	1292.00	XCSE
GENMAB A/S	15-Apr-2025	2:02:19 PM	14	1293.00	XCSE
GENMAB A/S	15-Apr-2025	2:03:17 PM	4	1294.00	XCSE
GENMAB A/S	15-Apr-2025	2:03:17 PM	110	1294.00	XCSE
GENMAB A/S	15-Apr-2025	2:03:18 PM	39	1293.50	XCSE
GENMAB A/S	15-Apr-2025	2:03:18 PM	36	1293.50	XCSE
GENMAB A/S	15-Apr-2025	2:03:18 PM	39	1294.00	XCSE
GENMAB A/S	15-Apr-2025	2:03:18 PM	51	1294.00	XCSE
GENMAB A/S	15-Apr-2025	2:03:18 PM	22	1294.00	XCSE
GENMAB A/S	15-Apr-2025	2:03:33 PM	51	1294.00	XCSE

101

Exhibit 99.1(a)

APPENDIX Share buy-back programme - Specification for April 14 – April 18, 2025

GENMAB A/S	15-Apr-2025	2:03:44 PM	7	1294.00	CEUX
GENMAB A/S	15-Apr-2025	2:03:47 PM	14	1294.00	CEUX
GENMAB A/S	15-Apr-2025	2:04:13 PM	39	1294.00	XCSE
GENMAB A/S	15-Apr-2025	2:04:33 PM	8	1294.00	XCSE
GENMAB A/S	15-Apr-2025	2:04:33 PM	80	1294.00	XCSE
GENMAB A/S	15-Apr-2025	2:04:33 PM	15	1294.00	CEUX
GENMAB A/S	15-Apr-2025	2:05:47 PM	28	1295.50	XCSE
GENMAB A/S	15-Apr-2025	2:05:47 PM	27	1295.50	XCSE
GENMAB A/S	15-Apr-2025	2:05:47 PM	34	1295.50	XCSE
GENMAB A/S	15-Apr-2025	2:05:47 PM	18	1295.50	CEUX
GENMAB A/S	15-Apr-2025	2:05:47 PM	7	1295.50	CEUX
GENMAB A/S	15-Apr-2025	2:06:51 PM	85	1295.00	CEUX
GENMAB A/S	15-Apr-2025	2:07:12 PM	14	1295.50	CEUX
GENMAB A/S	15-Apr-2025	2:07:12 PM	12	1295.50	CEUX
GENMAB A/S	15-Apr-2025	2:07:41 PM	76	1294.50	XCSE
GENMAB A/S	15-Apr-2025	2:07:41 PM	36	1295.50	CEUX
GENMAB A/S	15-Apr-2025	2:07:53 PM	45	1295.50	XCSE
GENMAB A/S	15-Apr-2025	2:07:53 PM	29	1295.50	XCSE
GENMAB A/S	15-Apr-2025	2:08:22 PM	34	1295.50	TQEX
GENMAB A/S	15-Apr-2025	2:08:22 PM	86	1295.50	CEUX
GENMAB A/S	15-Apr-2025	2:08:39 PM	114	1296.00	XCSE
GENMAB A/S	15-Apr-2025	2:08:39 PM	31	1296.00	CEUX
GENMAB A/S	15-Apr-2025	2:08:39 PM	13	1296.00	CEUX
GENMAB A/S	15-Apr-2025	2:08:40 PM	29	1296.00	CEUX
GENMAB A/S	15-Apr-2025	2:08:50 PM	91	1297.50	XCSE
GENMAB A/S	15-Apr-2025	2:09:21 PM	40	1297.50	AQEU
GENMAB A/S	15-Apr-2025	2:10:12 PM	33	1296.50	XCSE
GENMAB A/S	15-Apr-2025	2:10:12 PM	57	1296.50	XCSE
GENMAB A/S	15-Apr-2025	2:10:12 PM	34	1297.00	TQEX
GENMAB A/S	15-Apr-2025	2:10:12 PM	86	1297.00	CEUX
GENMAB A/S	15-Apr-2025	2:10:12 PM	36	1297.00	CEUX
GENMAB A/S	15-Apr-2025	2:10:13 PM	27	1297.00	CEUX
GENMAB A/S	15-Apr-2025	2:10:33 PM	12	1297.00	CEUX
GENMAB A/S	15-Apr-2025	2:11:23 PM	23	1297.00	CEUX
GENMAB A/S	15-Apr-2025	2:12:00 PM	11	1297.00	CEUX
GENMAB A/S	15-Apr-2025	2:12:31 PM	8	1295.50	XCSE
GENMAB A/S	15-Apr-2025	2:12:31 PM	42	1296.50	AQEU
GENMAB A/S	15-Apr-2025	2:13:41 PM	36	1296.50	CEUX
GENMAB A/S	15-Apr-2025	2:13:41 PM	2	1296.50	CEUX
GENMAB A/S	15-Apr-2025	2:13:41 PM	32	1296.50	CEUX
GENMAB A/S	15-Apr-2025	2:13:41 PM	12	1296.50	CEUX
GENMAB A/S	15-Apr-2025	2:13:50 PM	36	1296.50	CEUX
GENMAB A/S	15-Apr-2025	2:13:59 PM	16	1296.00	CEUX

102

Exhibit 99.1(a)

APPENDIX Share buy-back programme - Specification for April 14 – April 18, 2025

GENMAB A/S	15-Apr-2025	2:14:29 PM	26	1296.50	XCSE
GENMAB A/S	15-Apr-2025	2:14:30 PM	14	1296.50	XCSE
GENMAB A/S	15-Apr-2025	2:14:30 PM	26	1296.50	XCSE
GENMAB A/S	15-Apr-2025	2:14:30 PM	13	1296.50	XCSE
GENMAB A/S	15-Apr-2025	2:14:30 PM	14	1296.50	CEUX
GENMAB A/S	15-Apr-2025	2:16:31 PM	26	1296.00	XCSE
GENMAB A/S	15-Apr-2025	2:16:31 PM	30	1296.00	XCSE
GENMAB A/S	15-Apr-2025	2:16:31 PM	13	1296.00	XCSE
GENMAB A/S	15-Apr-2025	2:16:31 PM	32	1296.00	TQEX
GENMAB A/S	15-Apr-2025	2:16:31 PM	72	1296.00	CEUX
GENMAB A/S	15-Apr-2025	2:16:31 PM	32	1296.00	CEUX
GENMAB A/S	15-Apr-2025	2:17:01 PM	4	1296.50	AQEU
GENMAB A/S	15-Apr-2025	2:17:11 PM	91	1296.50	XCSE
GENMAB A/S	15-Apr-2025	2:18:11 PM	22	1296.50	AQEU
GENMAB A/S	15-Apr-2025	2:18:12 PM	4	1296.50	CEUX
GENMAB A/S	15-Apr-2025	2:18:22 PM	114	1296.50	XCSE
GENMAB A/S	15-Apr-2025	2:19:40 PM	87	1296.00	CEUX
GENMAB A/S	15-Apr-2025	2:19:40 PM	36	1296.50	CEUX
GENMAB A/S	15-Apr-2025	2:19:40 PM	25	1296.50	CEUX
GENMAB A/S	15-Apr-2025	2:19:46 PM	82	1295.50	XCSE
GENMAB A/S	15-Apr-2025	2:20:55 PM	13	1296.00	XCSE
GENMAB A/S	15-Apr-2025	2:20:55 PM	15	1296.00	XCSE
GENMAB A/S	15-Apr-2025	2:20:56 PM	41	1296.00	XCSE
GENMAB A/S	15-Apr-2025	2:21:29 PM	24	1296.00	XCSE
GENMAB A/S	15-Apr-2025	2:22:21 PM	38	1295.50	AQEU
GENMAB A/S	15-Apr-2025	2:22:21 PM	25	1295.50	CEUX
GENMAB A/S	15-Apr-2025	2:23:52 PM	85	1295.50	XCSE
GENMAB A/S	15-Apr-2025	2:23:52 PM	37	1296.00	XCSE
GENMAB A/S	15-Apr-2025	2:23:52 PM	15	1296.00	XCSE
GENMAB A/S	15-Apr-2025	2:23:52 PM	16	1296.00	XCSE
GENMAB A/S	15-Apr-2025	2:23:52 PM	46	1296.00	XCSE
GENMAB A/S	15-Apr-2025	2:23:52 PM	27	1295.00	TQEX
GENMAB A/S	15-Apr-2025	2:23:52 PM	25	1295.50	AQEU
GENMAB A/S	15-Apr-2025	2:23:52 PM	36	1296.00	CEUX
GENMAB A/S	15-Apr-2025	2:23:52 PM	7	1296.00	CEUX
GENMAB A/S	15-Apr-2025	2:23:52 PM	85	1295.00	CEUX
GENMAB A/S	15-Apr-2025	2:23:53 PM	48	1295.50	XCSE
GENMAB A/S	15-Apr-2025	2:23:54 PM	15	1295.50	XCSE
GENMAB A/S	15-Apr-2025	2:23:54 PM	17	1295.50	CEUX
GENMAB A/S	15-Apr-2025	2:23:54 PM	32	1295.50	CEUX
GENMAB A/S	15-Apr-2025	2:24:05 PM	15	1295.50	XCSE
GENMAB A/S	15-Apr-2025	2:24:06 PM	15	1295.50	XCSE
GENMAB A/S	15-Apr-2025	2:24:06 PM	23	1295.50	XCSE

103

Exhibit 99.1(a)

APPENDIX Share buy-back programme - Specification for April 14 – April 18, 2025

GENMAB A/S	15-Apr-2025	2:24:06 PM	13	1295.50	XCSE
GENMAB A/S	15-Apr-2025	2:24:06 PM	14	1295.50	XCSE
GENMAB A/S	15-Apr-2025	2:24:06 PM	13	1295.50	XCSE
GENMAB A/S	15-Apr-2025	2:24:06 PM	16	1295.50	XCSE
GENMAB A/S	15-Apr-2025	2:24:06 PM	34	1295.50	XCSE
GENMAB A/S	15-Apr-2025	2:24:06 PM	17	1295.50	XCSE
GENMAB A/S	15-Apr-2025	2:24:06 PM	38	1295.50	CEUX
GENMAB A/S	15-Apr-2025	2:24:07 PM	85	1295.00	XCSE
GENMAB A/S	15-Apr-2025	2:24:17 PM	35	1294.50	XCSE
GENMAB A/S	15-Apr-2025	2:24:17 PM	13	1294.50	XCSE
GENMAB A/S	15-Apr-2025	2:24:17 PM	88	1294.00	XCSE
GENMAB A/S	15-Apr-2025	2:24:17 PM	25	1294.00	TQEX
GENMAB A/S	15-Apr-2025	2:24:17 PM	36	1294.50	AQEU
GENMAB A/S	15-Apr-2025	2:24:17 PM	89	1294.50	CEUX
GENMAB A/S	15-Apr-2025	2:24:17 PM	43	1293.50	CEUX
GENMAB A/S	15-Apr-2025	2:24:21 PM	47	1293.50	CEUX
GENMAB A/S	15-Apr-2025	2:24:28 PM	89	1293.00	XCSE
GENMAB A/S	15-Apr-2025	2:25:51 PM	67	1294.00	XCSE
GENMAB A/S	15-Apr-2025	2:25:51 PM	24	1294.00	XCSE
GENMAB A/S	15-Apr-2025	2:27:59 PM	26	1293.50	XCSE
GENMAB A/S	15-Apr-2025	2:27:59 PM	1	1293.50	XCSE
GENMAB A/S	15-Apr-2025	2:27:59 PM	15	1293.50	XCSE
GENMAB A/S	15-Apr-2025	2:27:59 PM	75	1293.00	XCSE
GENMAB A/S	15-Apr-2025	2:27:59 PM	9	1293.00	XCSE
GENMAB A/S	15-Apr-2025	2:27:59 PM	88	1293.50	CEUX
GENMAB A/S	15-Apr-2025	2:29:11 PM	87	1292.50	XCSE
GENMAB A/S	15-Apr-2025	2:29:11 PM	25	1292.50	TQEX
GENMAB A/S	15-Apr-2025	2:29:11 PM	58	1292.50	CEUX
GENMAB A/S	15-Apr-2025	2:29:11 PM	28	1292.50	CEUX
GENMAB A/S	15-Apr-2025	2:33:11 PM	80	1293.50	XCSE
GENMAB A/S	15-Apr-2025	2:33:11 PM	11	1293.50	XCSE
GENMAB A/S	15-Apr-2025	2:33:11 PM	43	1293.50	TQEX
GENMAB A/S	15-Apr-2025	2:33:11 PM	90	1293.50	CEUX
GENMAB A/S	15-Apr-2025	2:33:13 PM	88	1293.50	XCSE
GENMAB A/S	15-Apr-2025	2:33:13 PM	85	1293.50	CEUX
GENMAB A/S	15-Apr-2025	2:33:21 PM	13	1294.00	XCSE
GENMAB A/S	15-Apr-2025	2:33:21 PM	13	1294.00	XCSE
GENMAB A/S	15-Apr-2025	2:33:21 PM	14	1294.00	XCSE
GENMAB A/S	15-Apr-2025	2:34:52 PM	56	1293.50	XCSE
GENMAB A/S	15-Apr-2025	2:35:04 PM	41	1295.50	AQEU
GENMAB A/S	15-Apr-2025	2:36:41 PM	87	1294.50	XCSE
GENMAB A/S	15-Apr-2025	2:36:41 PM	7	1295.00	CEUX
GENMAB A/S	15-Apr-2025	2:38:22 PM	39	1297.00	XCSE

104

Exhibit 99.1(a)

APPENDIX Share buy-back programme - Specification for April 14 – April 18, 2025

GENMAB A/S	15-Apr-2025	2:38:22 PM	14	1297.00	XCSE
GENMAB A/S	15-Apr-2025	2:38:22 PM	14	1297.00	XCSE
GENMAB A/S	15-Apr-2025	2:38:22 PM	46	1297.00	XCSE
GENMAB A/S	15-Apr-2025	2:38:22 PM	1	1297.00	XCSE
GENMAB A/S	15-Apr-2025	2:38:22 PM	39	1297.00	XCSE
GENMAB A/S	15-Apr-2025	2:38:22 PM	20	1297.00	XCSE
GENMAB A/S	15-Apr-2025	2:38:22 PM	6	1296.50	CEUX
GENMAB A/S	15-Apr-2025	2:38:23 PM	48	1297.00	XCSE
GENMAB A/S	15-Apr-2025	2:38:50 PM	87	1297.00	XCSE
GENMAB A/S	15-Apr-2025	2:38:50 PM	41	1297.00	TQEX
GENMAB A/S	15-Apr-2025	2:38:50 PM	84	1297.00	CEUX
GENMAB A/S	15-Apr-2025	2:38:52 PM	39	1297.00	XCSE
GENMAB A/S	15-Apr-2025	2:38:52 PM	14	1297.00	AQEU
GENMAB A/S	15-Apr-2025	2:39:28 PM	85	1298.50	XCSE
GENMAB A/S	15-Apr-2025	2:39:28 PM	35	1298.50	XCSE
GENMAB A/S	15-Apr-2025	2:39:28 PM	25	1298.50	XCSE
GENMAB A/S	15-Apr-2025	2:39:28 PM	35	1298.50	XCSE
GENMAB A/S	15-Apr-2025	2:39:28 PM	15	1298.50	XCSE
GENMAB A/S	15-Apr-2025	2:39:28 PM	87	1298.50	CEUX
GENMAB A/S	15-Apr-2025	2:39:46 PM	50	1298.50	XCSE
GENMAB A/S	15-Apr-2025	2:39:47 PM	36	1298.50	XCSE
GENMAB A/S	15-Apr-2025	2:40:01 PM	25	1298.50	XCSE
GENMAB A/S	15-Apr-2025	2:40:35 PM	114	1298.50	XCSE
GENMAB A/S	15-Apr-2025	2:40:35 PM	32	1298.50	CEUX
GENMAB A/S	15-Apr-2025	2:40:37 PM	89	1297.50	XCSE
GENMAB A/S	15-Apr-2025	2:40:37 PM	30	1298.00	TQEX
GENMAB A/S	15-Apr-2025	2:40:37 PM	40	1298.00	AQEU
GENMAB A/S	15-Apr-2025	2:40:37 PM	30	1297.50	CEUX
GENMAB A/S	15-Apr-2025	2:40:37 PM	54	1297.50	CEUX
GENMAB A/S	15-Apr-2025	2:40:39 PM	13	1297.00	TQEX
GENMAB A/S	15-Apr-2025	2:43:02 PM	34	1299.50	XCSE
GENMAB A/S	15-Apr-2025	2:43:02 PM	30	1299.50	XCSE
GENMAB A/S	15-Apr-2025	2:43:05 PM	149	1300.00	XCSE
GENMAB A/S	15-Apr-2025	2:43:05 PM	25	1300.00	TQEX
GENMAB A/S	15-Apr-2025	2:43:05 PM	52	1300.00	CEUX
GENMAB A/S	15-Apr-2025	2:43:46 PM	37	1300.50	TQEX
GENMAB A/S	15-Apr-2025	2:43:46 PM	64	1300.50	CEUX
GENMAB A/S	15-Apr-2025	2:43:46 PM	27	1300.50	CEUX
GENMAB A/S	15-Apr-2025	2:43:57 PM	85	1301.00	XCSE
GENMAB A/S	15-Apr-2025	2:43:57 PM	5	1301.00	AQEU
GENMAB A/S	15-Apr-2025	2:43:57 PM	29	1301.00	AQEU
GENMAB A/S	15-Apr-2025	2:43:59 PM	84	1300.00	XCSE
GENMAB A/S	15-Apr-2025	2:43:59 PM	1	1300.00	XCSE

105

Exhibit 99.1(a)

APPENDIX Share buy-back programme - Specification for April 14 – April 18, 2025

GENMAB A/S	15-Apr-2025	2:43:59 PM	90	1300.50	CEUX
GENMAB A/S	15-Apr-2025	2:44:00 PM	36	1300.00	AQEU
GENMAB A/S	15-Apr-2025	2:44:04 PM	60	1299.50	CEUX
GENMAB A/S	15-Apr-2025	2:44:04 PM	27	1299.50	CEUX
GENMAB A/S	15-Apr-2025	2:44:25 PM	14	1299.50	CEUX
GENMAB A/S	15-Apr-2025	2:44:32 PM	72	1299.50	CEUX
GENMAB A/S	15-Apr-2025	2:44:40 PM	89	1299.00	XCSE
GENMAB A/S	15-Apr-2025	2:45:45 PM	90	1300.00	XCSE
GENMAB A/S	15-Apr-2025	2:46:27 PM	85	1300.50	XCSE
GENMAB A/S	15-Apr-2025	2:46:27 PM	25	1300.50	TQEX
GENMAB A/S	15-Apr-2025	2:47:38 PM	34	1300.50	XCSE
GENMAB A/S	15-Apr-2025	2:48:14 PM	34	1301.00	TQEX
GENMAB A/S	15-Apr-2025	2:48:14 PM	28	1301.00	AQEU
GENMAB A/S	15-Apr-2025	2:48:18 PM	52	1300.50	XCSE
GENMAB A/S	15-Apr-2025	2:49:03 PM	85	1300.50	CEUX
GENMAB A/S	15-Apr-2025	2:50:51 PM	91	1300.50	XCSE
GENMAB A/S	15-Apr-2025	2:50:51 PM	91	1300.50	CEUX
GENMAB A/S	15-Apr-2025	2:50:52 PM	15	1300.00	AQEU
GENMAB A/S	15-Apr-2025	2:50:55 PM	2	1300.00	AQEU
GENMAB A/S	15-Apr-2025	2:51:02 PM	10	1300.00	AQEU
GENMAB A/S	15-Apr-2025	2:51:03 PM	18	1299.00	AQEU
GENMAB A/S	15-Apr-2025	2:51:03 PM	38	1299.50	CEUX
GENMAB A/S	15-Apr-2025	2:51:13 PM	47	1300.00	XCSE
GENMAB A/S	15-Apr-2025	2:51:13 PM	35	1300.00	XCSE
GENMAB A/S	15-Apr-2025	2:51:13 PM	13	1300.00	XCSE
GENMAB A/S	15-Apr-2025	2:51:13 PM	15	1300.00	XCSE
GENMAB A/S	15-Apr-2025	2:51:13 PM	4	1300.00	XCSE
GENMAB A/S	15-Apr-2025	2:52:23 PM	42	1300.00	XCSE
GENMAB A/S	15-Apr-2025	2:52:23 PM	13	1300.00	XCSE
GENMAB A/S	15-Apr-2025	2:52:23 PM	2	1300.00	XCSE
GENMAB A/S	15-Apr-2025	2:52:23 PM	34	1300.00	XCSE
GENMAB A/S	15-Apr-2025	2:52:23 PM	14	1300.00	XCSE
GENMAB A/S	15-Apr-2025	2:52:23 PM	9	1300.00	XCSE
GENMAB A/S	15-Apr-2025	2:53:01 PM	90	1299.00	XCSE
GENMAB A/S	15-Apr-2025	2:53:45 PM	15	1299.50	TQEX
GENMAB A/S	15-Apr-2025	2:53:45 PM	87	1300.00	CEUX
GENMAB A/S	15-Apr-2025	2:53:45 PM	4	1300.00	CEUX
GENMAB A/S	15-Apr-2025	2:54:13 PM	6	1300.00	XCSE
GENMAB A/S	15-Apr-2025	2:54:13 PM	13	1300.00	XCSE
GENMAB A/S	15-Apr-2025	2:54:13 PM	88	1300.00	XCSE
GENMAB A/S	15-Apr-2025	2:54:34 PM	88	1300.00	CEUX
GENMAB A/S	15-Apr-2025	2:55:23 PM	21	1300.50	XCSE
GENMAB A/S	15-Apr-2025	2:55:23 PM	1	1300.50	XCSE

106

Exhibit 99.1(a)

APPENDIX Share buy-back programme - Specification for April 14 – April 18, 2025

GENMAB A/S	15-Apr-2025	2:55:23 PM	2	1300.50	XCSE
GENMAB A/S	15-Apr-2025	2:57:11 PM	85	1300.00	XCSE
GENMAB A/S	15-Apr-2025	2:57:11 PM	21	1300.50	TQEX
GENMAB A/S	15-Apr-2025	2:57:11 PM	5	1300.50	TQEX
GENMAB A/S	15-Apr-2025	2:57:24 PM	88	1300.50	XCSE
GENMAB A/S	15-Apr-2025	2:58:51 PM	35	1301.00	XCSE
GENMAB A/S	15-Apr-2025	2:58:51 PM	26	1301.00	XCSE
GENMAB A/S	15-Apr-2025	2:58:51 PM	31	1301.00	AQEU
GENMAB A/S	15-Apr-2025	2:58:51 PM	84	1301.00	CEUX
GENMAB A/S	15-Apr-2025	2:59:25 PM	58	1301.50	XCSE
GENMAB A/S	15-Apr-2025	2:59:25 PM	17	1301.50	XCSE
GENMAB A/S	15-Apr-2025	2:59:25 PM	14	1301.50	XCSE
GENMAB A/S	15-Apr-2025	2:59:25 PM	43	1301.50	XCSE
GENMAB A/S	15-Apr-2025	3:00:49 PM	2	1301.50	XCSE
GENMAB A/S	15-Apr-2025	3:00:49 PM	1	1301.50	XCSE
GENMAB A/S	15-Apr-2025	3:00:49 PM	32	1301.50	CEUX
GENMAB A/S	15-Apr-2025	3:01:51 PM	84	1302.00	XCSE
GENMAB A/S	15-Apr-2025	3:01:51 PM	35	1302.00	XCSE
GENMAB A/S	15-Apr-2025	3:01:51 PM	20	1302.00	XCSE
GENMAB A/S	15-Apr-2025	3:01:51 PM	17	1302.00	XCSE
GENMAB A/S	15-Apr-2025	3:01:51 PM	42	1302.00	XCSE
GENMAB A/S	15-Apr-2025	3:01:51 PM	2	1302.00	CEUX
GENMAB A/S	15-Apr-2025	3:01:51 PM	89	1302.00	CEUX
GENMAB A/S	15-Apr-2025	3:01:52 PM	4	1302.00	XCSE
GENMAB A/S	15-Apr-2025	3:01:52 PM	35	1302.00	XCSE
GENMAB A/S	15-Apr-2025	3:01:52 PM	27	1302.00	XCSE
GENMAB A/S	15-Apr-2025	3:01:52 PM	16	1302.00	XCSE
GENMAB A/S	15-Apr-2025	3:01:52 PM	32	1302.00	XCSE
GENMAB A/S	15-Apr-2025	3:02:49 PM	47	1301.50	XCSE
GENMAB A/S	15-Apr-2025	3:02:49 PM	20	1301.50	XCSE
GENMAB A/S	15-Apr-2025	3:02:49 PM	24	1301.50	XCSE
GENMAB A/S	15-Apr-2025	3:02:49 PM	17	1301.50	XCSE
GENMAB A/S	15-Apr-2025	3:02:49 PM	2	1301.50	XCSE
GENMAB A/S	15-Apr-2025	3:02:53 PM	91	1300.50	XCSE
GENMAB A/S	15-Apr-2025	3:02:53 PM	28	1300.50	TQEX
GENMAB A/S	15-Apr-2025	3:02:53 PM	10	1299.50	TQEX
GENMAB A/S	15-Apr-2025	3:02:53 PM	25	1301.00	AQEU
GENMAB A/S	15-Apr-2025	3:02:53 PM	27	1300.00	AQEU
GENMAB A/S	15-Apr-2025	3:02:53 PM	15	1299.00	AQEU
GENMAB A/S	15-Apr-2025	3:02:53 PM	88	1301.00	CEUX
GENMAB A/S	15-Apr-2025	3:02:53 PM	84	1300.00	CEUX
GENMAB A/S	15-Apr-2025	3:02:54 PM	84	1299.50	CEUX
GENMAB A/S	15-Apr-2025	3:04:43 PM	81	1300.50	XCSE

107

Exhibit 99.1(a)

APPENDIX Share buy-back programme - Specification for April 14 – April 18, 2025

GENMAB A/S	15-Apr-2025	3:05:19 PM	87	1300.00	XCSE
GENMAB A/S	15-Apr-2025	3:08:08 PM	12	1301.00	CEUX
GENMAB A/S	15-Apr-2025	3:08:30 PM	89	1301.00	XCSE
GENMAB A/S	15-Apr-2025	3:09:25 PM	71	1301.50	CEUX
GENMAB A/S	15-Apr-2025	3:10:19 PM	35	1301.50	CEUX
GENMAB A/S	15-Apr-2025	3:10:19 PM	7	1301.50	CEUX
GENMAB A/S	15-Apr-2025	3:10:26 PM	43	1300.50	TQEX
GENMAB A/S	15-Apr-2025	3:10:26 PM	25	1300.50	AQEU
GENMAB A/S	15-Apr-2025	3:10:26 PM	32	1301.00	CEUX
GENMAB A/S	15-Apr-2025	3:10:26 PM	90	1300.50	CEUX
GENMAB A/S	15-Apr-2025	3:11:01 PM	88	1300.00	XCSE
GENMAB A/S	15-Apr-2025	3:11:31 PM	22	1300.50	AQEU
GENMAB A/S	15-Apr-2025	3:11:31 PM	72	1300.50	CEUX
GENMAB A/S	15-Apr-2025	3:11:36 PM	19	1300.50	CEUX
GENMAB A/S	15-Apr-2025	3:11:43 PM	3	1300.50	AQEU
GENMAB A/S	15-Apr-2025	3:12:41 PM	84	1300.00	XCSE
GENMAB A/S	15-Apr-2025	3:13:14 PM	15	1300.50	XCSE
GENMAB A/S	15-Apr-2025	3:13:14 PM	16	1300.50	XCSE
GENMAB A/S	15-Apr-2025	3:13:51 PM	53	1300.50	XCSE
GENMAB A/S	15-Apr-2025	3:13:51 PM	37	1300.50	XCSE
GENMAB A/S	15-Apr-2025	3:13:51 PM	42	1300.50	TQEX
GENMAB A/S	15-Apr-2025	3:13:51 PM	90	1300.50	CEUX
GENMAB A/S	15-Apr-2025	3:15:22 PM	85	1302.00	XCSE
GENMAB A/S	15-Apr-2025	3:15:22 PM	90	1302.00	CEUX
GENMAB A/S	15-Apr-2025	3:16:12 PM	25	1302.00	XCSE
GENMAB A/S	15-Apr-2025	3:16:21 PM	64	1302.00	XCSE
GENMAB A/S	15-Apr-2025	3:16:45 PM	85	1302.50	XCSE
GENMAB A/S	15-Apr-2025	3:16:45 PM	56	1302.50	CEUX
GENMAB A/S	15-Apr-2025	3:18:02 PM	35	1302.50	AQEU
GENMAB A/S	15-Apr-2025	3:18:02 PM	30	1302.50	CEUX
GENMAB A/S	15-Apr-2025	3:18:23 PM	32	1302.50	CEUX
GENMAB A/S	15-Apr-2025	3:18:51 PM	38	1302.00	TQEX
GENMAB A/S	15-Apr-2025	3:19:37 PM	7	1302.50	CEUX
GENMAB A/S	15-Apr-2025	3:19:37 PM	13	1302.50	CEUX
GENMAB A/S	15-Apr-2025	3:19:37 PM	8	1302.50	CEUX
GENMAB A/S	15-Apr-2025	3:19:37 PM	1	1302.50	CEUX
GENMAB A/S	15-Apr-2025	3:19:37 PM	8	1302.50	CEUX
GENMAB A/S	15-Apr-2025	3:19:37 PM	7	1302.50	CEUX
GENMAB A/S	15-Apr-2025	3:19:43 PM	34	1302.50	XCSE
GENMAB A/S	15-Apr-2025	3:19:43 PM	16	1302.50	XCSE
GENMAB A/S	15-Apr-2025	3:19:43 PM	17	1302.50	XCSE
GENMAB A/S	15-Apr-2025	3:19:43 PM	16	1302.50	XCSE
GENMAB A/S	15-Apr-2025	3:19:43 PM	7	1302.50	CEUX

108

Exhibit 99.1(a)

APPENDIX Share buy-back programme - Specification for April 14 – April 18, 2025

GENMAB A/S	15-Apr-2025	3:19:43 PM	18	1302.50	CEUX
GENMAB A/S	15-Apr-2025	3:20:11 PM	3	1302.50	CEUX
GENMAB A/S	15-Apr-2025	3:20:11 PM	3	1302.50	CEUX
GENMAB A/S	15-Apr-2025	3:20:11 PM	19	1302.50	CEUX
GENMAB A/S	15-Apr-2025	3:21:01 PM	40	1302.50	TQEX
GENMAB A/S	15-Apr-2025	3:21:01 PM	16	1302.50	CEUX
GENMAB A/S	15-Apr-2025	3:21:01 PM	8	1302.50	CEUX
GENMAB A/S	15-Apr-2025	3:21:01 PM	31	1302.50	CEUX
GENMAB A/S	15-Apr-2025	3:21:04 PM	46	1302.00	XCSE
GENMAB A/S	15-Apr-2025	3:21:04 PM	24	1302.00	XCSE
GENMAB A/S	15-Apr-2025	3:21:04 PM	15	1302.00	XCSE
GENMAB A/S	15-Apr-2025	3:21:04 PM	15	1302.00	XCSE
GENMAB A/S	15-Apr-2025	3:21:04 PM	48	1302.00	XCSE
GENMAB A/S	15-Apr-2025	3:21:04 PM	17	1302.00	XCSE
GENMAB A/S	15-Apr-2025	3:21:04 PM	15	1302.00	XCSE
GENMAB A/S	15-Apr-2025	3:21:04 PM	24	1302.00	XCSE
GENMAB A/S	15-Apr-2025	3:21:04 PM	32	1302.00	CEUX
GENMAB A/S	15-Apr-2025	3:21:05 PM	17	1302.00	XCSE
GENMAB A/S	15-Apr-2025	3:21:05 PM	16	1302.00	XCSE
GENMAB A/S	15-Apr-2025	3:21:05 PM	14	1302.00	XCSE
GENMAB A/S	15-Apr-2025	3:21:05 PM	67	1302.00	XCSE
GENMAB A/S	15-Apr-2025	3:21:05 PM	9	1302.00	XCSE
GENMAB A/S	15-Apr-2025	3:21:05 PM	14	1302.00	XCSE
GENMAB A/S	15-Apr-2025	3:21:06 PM	42	1302.00	XCSE
GENMAB A/S	15-Apr-2025	3:21:06 PM	49	1302.00	XCSE
GENMAB A/S	15-Apr-2025	3:21:06 PM	45	1302.00	XCSE
GENMAB A/S	15-Apr-2025	3:21:06 PM	12	1301.50	CEUX
GENMAB A/S	15-Apr-2025	3:21:15 PM	35	1301.50	XCSE
GENMAB A/S	15-Apr-2025	3:21:15 PM	14	1301.50	XCSE
GENMAB A/S	15-Apr-2025	3:21:15 PM	16	1301.50	XCSE
GENMAB A/S	15-Apr-2025	3:21:15 PM	24	1301.50	XCSE
GENMAB A/S	15-Apr-2025	3:21:15 PM	24	1302.00	XCSE
GENMAB A/S	15-Apr-2025	3:21:15 PM	1	1302.00	XCSE
GENMAB A/S	15-Apr-2025	3:21:15 PM	36	1301.50	AQEU
GENMAB A/S	15-Apr-2025	3:21:15 PM	75	1301.50	CEUX
GENMAB A/S	15-Apr-2025	3:22:20 PM	81	1302.00	XCSE
GENMAB A/S	15-Apr-2025	3:22:20 PM	9	1302.50	CEUX
GENMAB A/S	15-Apr-2025	3:22:20 PM	13	1302.50	CEUX
GENMAB A/S	15-Apr-2025	3:22:20 PM	7	1302.50	CEUX
GENMAB A/S	15-Apr-2025	3:22:20 PM	4	1302.50	CEUX
GENMAB A/S	15-Apr-2025	3:22:23 PM	36	1302.00	TQEX
GENMAB A/S	15-Apr-2025	3:22:37 PM	50	1302.50	CEUX
GENMAB A/S	15-Apr-2025	3:23:01 PM	37	1302.50	CEUX

109

Exhibit 99.1(a)

APPENDIX Share buy-back programme - Specification for April 14 – April 18, 2025

GENMAB A/S	15-Apr-2025	3:23:14 PM	37	1302.50	AQEU
GENMAB A/S	15-Apr-2025	3:23:53 PM	49	1303.00	CEUX
GENMAB A/S	15-Apr-2025	3:23:53 PM	4	1303.00	CEUX
GENMAB A/S	15-Apr-2025	3:24:05 PM	114	1302.50	XCSE
GENMAB A/S	15-Apr-2025	3:24:05 PM	9	1302.00	XCSE
GENMAB A/S	15-Apr-2025	3:24:05 PM	36	1302.50	AQEU
GENMAB A/S	15-Apr-2025	3:24:05 PM	91	1302.50	CEUX
GENMAB A/S	15-Apr-2025	3:24:16 PM	89	1302.50	XCSE
GENMAB A/S	15-Apr-2025	3:24:17 PM	26	1302.50	AQEU
GENMAB A/S	15-Apr-2025	3:24:17 PM	84	1302.50	CEUX
GENMAB A/S	15-Apr-2025	3:25:11 PM	91	1303.00	XCSE
GENMAB A/S	15-Apr-2025	3:25:11 PM	87	1303.00	XCSE
GENMAB A/S	15-Apr-2025	3:25:11 PM	3	1303.00	XCSE
GENMAB A/S	15-Apr-2025	3:25:11 PM	1	1303.00	XCSE
GENMAB A/S	15-Apr-2025	3:25:11 PM	25	1303.00	AQEU
GENMAB A/S	15-Apr-2025	3:26:34 PM	47	1303.00	XCSE
GENMAB A/S	15-Apr-2025	3:26:34 PM	35	1303.00	XCSE
GENMAB A/S	15-Apr-2025	3:26:34 PM	26	1303.00	XCSE
GENMAB A/S	15-Apr-2025	3:26:34 PM	6	1303.00	XCSE
GENMAB A/S	15-Apr-2025	3:26:34 PM	82	1302.00	XCSE
GENMAB A/S	15-Apr-2025	3:26:34 PM	2	1302.00	XCSE
GENMAB A/S	15-Apr-2025	3:26:34 PM	17	1302.50	XCSE
GENMAB A/S	15-Apr-2025	3:26:34 PM	17	1302.50	XCSE
GENMAB A/S	15-Apr-2025	3:26:34 PM	35	1302.50	XCSE
GENMAB A/S	15-Apr-2025	3:26:34 PM	16	1302.50	XCSE
GENMAB A/S	15-Apr-2025	3:26:34 PM	29	1302.50	XCSE
GENMAB A/S	15-Apr-2025	3:26:34 PM	4	1302.00	TQEX
GENMAB A/S	15-Apr-2025	3:26:34 PM	84	1302.50	CEUX
GENMAB A/S	15-Apr-2025	3:26:34 PM	25	1302.50	CEUX
GENMAB A/S	15-Apr-2025	3:26:34 PM	31	1302.50	CEUX
GENMAB A/S	15-Apr-2025	3:26:34 PM	8	1302.50	CEUX
GENMAB A/S	15-Apr-2025	3:26:34 PM	36	1303.00	CEUX
GENMAB A/S	15-Apr-2025	3:26:34 PM	8	1303.00	CEUX
GENMAB A/S	15-Apr-2025	3:26:34 PM	6	1303.00	CEUX
GENMAB A/S	15-Apr-2025	3:26:35 PM	16	1302.50	XCSE
GENMAB A/S	15-Apr-2025	3:26:35 PM	26	1302.50	XCSE
GENMAB A/S	15-Apr-2025	3:26:35 PM	16	1302.50	XCSE
GENMAB A/S	15-Apr-2025	3:26:35 PM	17	1302.50	XCSE
GENMAB A/S	15-Apr-2025	3:26:35 PM	14	1302.50	XCSE
GENMAB A/S	15-Apr-2025	3:26:35 PM	26	1302.50	XCSE
GENMAB A/S	15-Apr-2025	3:26:35 PM	57	1302.50	XCSE
GENMAB A/S	15-Apr-2025	3:26:35 PM	17	1302.50	XCSE
GENMAB A/S	15-Apr-2025	3:26:35 PM	14	1302.50	XCSE

110

Exhibit 99.1(a)

APPENDIX Share buy-back programme - Specification for April 14 – April 18, 2025

GENMAB A/S	15-Apr-2025	3:26:35 PM	26	1302.50	XCSE
GENMAB A/S	15-Apr-2025	3:26:35 PM	15	1302.50	XCSE
GENMAB A/S	15-Apr-2025	3:26:35 PM	41	1302.00	TQEX
GENMAB A/S	15-Apr-2025	3:26:36 PM	48	1302.50	XCSE
GENMAB A/S	15-Apr-2025	3:26:36 PM	16	1302.50	XCSE
GENMAB A/S	15-Apr-2025	3:26:36 PM	15	1302.50	XCSE
GENMAB A/S	15-Apr-2025	3:26:36 PM	26	1302.50	XCSE
GENMAB A/S	15-Apr-2025	3:26:36 PM	9	1302.50	XCSE
GENMAB A/S	15-Apr-2025	3:26:36 PM	30	1302.50	XCSE
GENMAB A/S	15-Apr-2025	3:26:36 PM	17	1302.50	XCSE
GENMAB A/S	15-Apr-2025	3:26:36 PM	14	1302.50	XCSE
GENMAB A/S	15-Apr-2025	3:26:37 PM	17	1302.50	XCSE
GENMAB A/S	15-Apr-2025	3:26:37 PM	26	1302.50	XCSE
GENMAB A/S	15-Apr-2025	3:26:57 PM	26	1302.50	AQEU
GENMAB A/S	15-Apr-2025	3:26:57 PM	84	1302.50	CEUX
GENMAB A/S	15-Apr-2025	3:27:21 PM	77	1302.00	XCSE
GENMAB A/S	15-Apr-2025	3:27:21 PM	9	1302.00	XCSE
GENMAB A/S	15-Apr-2025	3:27:26 PM	11	1302.00	TQEX
GENMAB A/S	15-Apr-2025	3:27:50 PM	13	1302.00	XCSE
GENMAB A/S	15-Apr-2025	3:27:50 PM	35	1302.00	XCSE
GENMAB A/S	15-Apr-2025	3:27:50 PM	14	1302.00	XCSE
GENMAB A/S	15-Apr-2025	3:27:50 PM	17	1302.00	XCSE
GENMAB A/S	15-Apr-2025	3:27:50 PM	85	1301.00	XCSE
GENMAB A/S	15-Apr-2025	3:27:50 PM	2	1301.00	TQEX
GENMAB A/S	15-Apr-2025	3:27:50 PM	2	1301.00	TQEX
GENMAB A/S	15-Apr-2025	3:27:50 PM	2	1301.00	TQEX
GENMAB A/S	15-Apr-2025	3:27:50 PM	2	1301.00	TQEX
GENMAB A/S	15-Apr-2025	3:27:50 PM	2	1301.00	TQEX
GENMAB A/S	15-Apr-2025	3:27:50 PM	3	1301.00	TQEX
GENMAB A/S	15-Apr-2025	3:27:50 PM	2	1301.50	AQEU
GENMAB A/S	15-Apr-2025	3:27:50 PM	2	1301.50	AQEU
GENMAB A/S	15-Apr-2025	3:27:50 PM	2	1301.50	AQEU
GENMAB A/S	15-Apr-2025	3:27:50 PM	2	1301.50	AQEU
GENMAB A/S	15-Apr-2025	3:27:50 PM	2	1301.50	AQEU
GENMAB A/S	15-Apr-2025	3:27:50 PM	31	1301.50	AQEU
GENMAB A/S	15-Apr-2025	3:27:50 PM	89	1301.50	CEUX
GENMAB A/S	15-Apr-2025	3:27:51 PM	16	1301.00	TQEX
GENMAB A/S	15-Apr-2025	3:27:51 PM	9	1300.50	CEUX
GENMAB A/S	15-Apr-2025	3:27:52 PM	35	1301.00	XCSE
GENMAB A/S	15-Apr-2025	3:27:52 PM	23	1301.00	XCSE
GENMAB A/S	15-Apr-2025	3:27:52 PM	13	1301.00	XCSE
GENMAB A/S	15-Apr-2025	3:27:52 PM	77	1300.50	CEUX
GENMAB A/S	15-Apr-2025	3:28:00 PM	89	1300.50	XCSE

111

Exhibit 99.1(a)

APPENDIX Share buy-back programme - Specification for April 14 – April 18, 2025

GENMAB A/S	15-Apr-2025	3:28:00 PM	5	1300.50	TQEX
GENMAB A/S	15-Apr-2025	3:28:00 PM	7	1300.50	TQEX
GENMAB A/S	15-Apr-2025	3:28:00 PM	5	1300.50	TQEX
GENMAB A/S	15-Apr-2025	3:28:00 PM	6	1300.50	TQEX
GENMAB A/S	15-Apr-2025	3:28:00 PM	11	1300.50	TQEX
GENMAB A/S	15-Apr-2025	3:28:00 PM	1	1300.50	CEUX
GENMAB A/S	15-Apr-2025	3:28:00 PM	4	1300.50	CEUX
GENMAB A/S	15-Apr-2025	3:28:00 PM	5	1300.50	CEUX
GENMAB A/S	15-Apr-2025	3:28:00 PM	6	1300.50	CEUX
GENMAB A/S	15-Apr-2025	3:28:00 PM	38	1300.50	CEUX
GENMAB A/S	15-Apr-2025	3:28:10 PM	35	1300.50	CEUX
GENMAB A/S	15-Apr-2025	3:28:13 PM	59	1301.00	CEUX
GENMAB A/S	15-Apr-2025	3:28:41 PM	62	1300.50	XCSE
GENMAB A/S	15-Apr-2025	3:29:11 PM	28	1300.50	XCSE
GENMAB A/S	15-Apr-2025	3:29:11 PM	31	1300.50	TQEX
GENMAB A/S	15-Apr-2025	3:30:00 PM	7	1301.00	XCSE
GENMAB A/S	15-Apr-2025	3:30:00 PM	14	1301.00	XCSE
GENMAB A/S	15-Apr-2025	3:30:00 PM	15	1301.00	XCSE
GENMAB A/S	15-Apr-2025	3:30:00 PM	15	1301.00	XCSE
GENMAB A/S	15-Apr-2025	3:30:00 PM	35	1301.00	XCSE
GENMAB A/S	15-Apr-2025	3:30:00 PM	31	1300.50	AQEU
GENMAB A/S	15-Apr-2025	3:30:00 PM	65	1301.00	CEUX
GENMAB A/S	15-Apr-2025	3:30:04 PM	91	1301.50	XCSE
GENMAB A/S	15-Apr-2025	3:30:04 PM	12	1301.00	XCSE
GENMAB A/S	15-Apr-2025	3:30:04 PM	13	1301.00	XCSE
GENMAB A/S	15-Apr-2025	3:30:04 PM	35	1301.50	XCSE
GENMAB A/S	15-Apr-2025	3:30:04 PM	46	1301.50	XCSE
GENMAB A/S	15-Apr-2025	3:30:04 PM	8	1301.50	XCSE
GENMAB A/S	15-Apr-2025	3:30:04 PM	6	1300.50	XCSE
GENMAB A/S	15-Apr-2025	3:30:04 PM	35	1301.00	TQEX
GENMAB A/S	15-Apr-2025	3:30:04 PM	76	1301.00	CEUX
GENMAB A/S	15-Apr-2025	3:30:11 PM	85	1300.50	XCSE
GENMAB A/S	15-Apr-2025	3:30:41 PM	25	1300.50	AQEU
GENMAB A/S	15-Apr-2025	3:30:52 PM	6	1299.50	XCSE
GENMAB A/S	15-Apr-2025	3:30:52 PM	2	1299.50	XCSE
GENMAB A/S	15-Apr-2025	3:30:52 PM	2	1299.50	XCSE
GENMAB A/S	15-Apr-2025	3:30:52 PM	2	1299.50	XCSE
GENMAB A/S	15-Apr-2025	3:30:52 PM	15	1299.50	XCSE
GENMAB A/S	15-Apr-2025	3:30:52 PM	5	1299.50	XCSE
GENMAB A/S	15-Apr-2025	3:30:52 PM	3	1299.50	XCSE
GENMAB A/S	15-Apr-2025	3:30:52 PM	2	1299.50	XCSE
GENMAB A/S	15-Apr-2025	3:30:52 PM	6	1299.50	XCSE
GENMAB A/S	15-Apr-2025	3:30:52 PM	63	1300.00	CEUX

112

Exhibit 99.1(a)

APPENDIX Share buy-back programme - Specification for April 14 – April 18, 2025

GENMAB A/S	15-Apr-2025	3:30:53 PM	19	1299.50	XCSE
GENMAB A/S	15-Apr-2025	3:30:53 PM	27	1299.50	XCSE
GENMAB A/S	15-Apr-2025	3:30:53 PM	14	1300.00	XCSE
GENMAB A/S	15-Apr-2025	3:30:53 PM	14	1300.00	XCSE
GENMAB A/S	15-Apr-2025	3:31:01 PM	90	1299.50	XCSE
GENMAB A/S	15-Apr-2025	3:31:21 PM	28	1299.50	AQEU
GENMAB A/S	15-Apr-2025	3:31:22 PM	18	1299.00	CEUX
GENMAB A/S	15-Apr-2025	3:31:29 PM	86	1299.00	XCSE
GENMAB A/S	15-Apr-2025	3:31:29 PM	29	1299.00	CEUX
GENMAB A/S	15-Apr-2025	3:31:51 PM	88	1299.00	XCSE
GENMAB A/S	15-Apr-2025	3:31:51 PM	33	1299.50	TQEX
GENMAB A/S	15-Apr-2025	3:31:53 PM	27	1299.50	CEUX
GENMAB A/S	15-Apr-2025	3:31:53 PM	16	1299.50	CEUX
GENMAB A/S	15-Apr-2025	3:32:03 PM	17	1299.50	CEUX
GENMAB A/S	15-Apr-2025	3:32:03 PM	13	1299.50	CEUX
GENMAB A/S	15-Apr-2025	3:32:03 PM	12	1299.50	CEUX
GENMAB A/S	15-Apr-2025	3:32:03 PM	46	1299.50	CEUX
GENMAB A/S	15-Apr-2025	3:32:05 PM	3	1300.00	XCSE
GENMAB A/S	15-Apr-2025	3:32:05 PM	79	1300.00	XCSE
GENMAB A/S	15-Apr-2025	3:32:07 PM	45	1300.50	XCSE
GENMAB A/S	15-Apr-2025	3:32:07 PM	39	1300.50	XCSE
GENMAB A/S	15-Apr-2025	3:32:07 PM	32	1300.50	TQEX
GENMAB A/S	15-Apr-2025	3:32:22 PM	31	1301.50	TQEX
GENMAB A/S	15-Apr-2025	3:32:27 PM	88	1301.00	XCSE
GENMAB A/S	15-Apr-2025	3:32:27 PM	48	1300.50	XCSE
GENMAB A/S	15-Apr-2025	3:32:27 PM	20	1300.50	XCSE
GENMAB A/S	15-Apr-2025	3:32:27 PM	35	1300.50	XCSE
GENMAB A/S	15-Apr-2025	3:32:27 PM	11	1300.50	XCSE
GENMAB A/S	15-Apr-2025	3:32:27 PM	86	1300.00	XCSE
GENMAB A/S	15-Apr-2025	3:32:27 PM	29	1301.00	AQEU
GENMAB A/S	15-Apr-2025	3:32:27 PM	26	1300.00	AQEU
GENMAB A/S	15-Apr-2025	3:32:27 PM	84	1301.00	CEUX
GENMAB A/S	15-Apr-2025	3:32:27 PM	86	1300.00	CEUX
GENMAB A/S	15-Apr-2025	3:32:30 PM	3	1299.50	XCSE
GENMAB A/S	15-Apr-2025	3:32:30 PM	14	1299.50	XCSE
GENMAB A/S	15-Apr-2025	3:32:30 PM	46	1299.50	XCSE
GENMAB A/S	15-Apr-2025	3:32:30 PM	2	1299.50	XCSE
GENMAB A/S	15-Apr-2025	3:32:30 PM	3	1299.50	XCSE
GENMAB A/S	15-Apr-2025	3:32:30 PM	5	1299.50	XCSE
GENMAB A/S	15-Apr-2025	3:32:30 PM	4	1299.50	XCSE
GENMAB A/S	15-Apr-2025	3:32:30 PM	3	1299.50	XCSE
GENMAB A/S	15-Apr-2025	3:32:30 PM	3	1299.50	XCSE
GENMAB A/S	15-Apr-2025	3:32:30 PM	5	1299.50	XCSE

113

Exhibit 99.1(a)

APPENDIX Share buy-back programme - Specification for April 14 – April 18, 2025

GENMAB A/S	15-Apr-2025	3:32:30 PM	3	1299.50	XCSE
GENMAB A/S	15-Apr-2025	3:32:30 PM	7	1299.50	XCSE
GENMAB A/S	15-Apr-2025	3:32:30 PM	16	1299.50	XCSE
GENMAB A/S	15-Apr-2025	3:32:30 PM	84	1300.00	CEUX
GENMAB A/S	15-Apr-2025	3:32:30 PM	12	1299.00	CEUX
GENMAB A/S	15-Apr-2025	3:32:30 PM	5	1299.00	CEUX
GENMAB A/S	15-Apr-2025	3:32:30 PM	8	1299.00	CEUX
GENMAB A/S	15-Apr-2025	3:32:30 PM	7	1299.00	CEUX
GENMAB A/S	15-Apr-2025	3:32:30 PM	6	1299.00	CEUX
GENMAB A/S	15-Apr-2025	3:32:30 PM	2	1299.00	CEUX
GENMAB A/S	15-Apr-2025	3:32:31 PM	17	1299.00	XCSE
GENMAB A/S	15-Apr-2025	3:32:31 PM	68	1299.00	XCSE
GENMAB A/S	15-Apr-2025	3:32:31 PM	47	1299.00	CEUX
GENMAB A/S	15-Apr-2025	3:32:32 PM	4	1299.00	XCSE
GENMAB A/S	15-Apr-2025	3:32:51 PM	89	1299.00	XCSE
GENMAB A/S	15-Apr-2025	3:33:02 PM	6	1299.00	XCSE
GENMAB A/S	15-Apr-2025	3:33:11 PM	35	1298.50	XCSE
GENMAB A/S	15-Apr-2025	3:33:11 PM	19	1298.50	XCSE
GENMAB A/S	15-Apr-2025	3:33:11 PM	17	1298.50	XCSE
GENMAB A/S	15-Apr-2025	3:33:11 PM	16	1298.50	XCSE
GENMAB A/S	15-Apr-2025	3:33:14 PM	88	1297.50	XCSE
GENMAB A/S	15-Apr-2025	3:33:14 PM	16	1297.50	XCSE
GENMAB A/S	15-Apr-2025	3:33:14 PM	14	1297.50	XCSE
GENMAB A/S	15-Apr-2025	3:33:14 PM	16	1297.50	XCSE
GENMAB A/S	15-Apr-2025	3:33:14 PM	49	1298.00	XCSE
GENMAB A/S	15-Apr-2025	3:33:14 PM	19	1298.00	XCSE
GENMAB A/S	15-Apr-2025	3:33:14 PM	28	1297.50	TQEX
GENMAB A/S	15-Apr-2025	3:33:14 PM	33	1298.00	AQEU
GENMAB A/S	15-Apr-2025	3:33:14 PM	89	1297.50	CEUX
GENMAB A/S	15-Apr-2025	3:33:31 PM	35	1298.00	XCSE
GENMAB A/S	15-Apr-2025	3:33:31 PM	13	1298.00	XCSE
GENMAB A/S	15-Apr-2025	3:33:31 PM	46	1298.00	XCSE
GENMAB A/S	15-Apr-2025	3:33:31 PM	17	1298.00	XCSE
GENMAB A/S	15-Apr-2025	3:33:31 PM	28	1298.00	AQEU
GENMAB A/S	15-Apr-2025	3:33:32 PM	48	1298.00	XCSE
GENMAB A/S	15-Apr-2025	3:33:32 PM	11	1298.00	XCSE
GENMAB A/S	15-Apr-2025	3:33:51 PM	87	1297.50	XCSE
GENMAB A/S	15-Apr-2025	3:34:01 PM	80	1298.00	XCSE
GENMAB A/S	15-Apr-2025	3:34:01 PM	9	1298.00	XCSE
GENMAB A/S	15-Apr-2025	3:34:01 PM	50	1298.00	XCSE
GENMAB A/S	15-Apr-2025	3:34:01 PM	12	1298.00	XCSE
GENMAB A/S	15-Apr-2025	3:34:19 PM	21	1299.50	CEUX
GENMAB A/S	15-Apr-2025	3:34:20 PM	54	1299.50	CEUX

114

Exhibit 99.1(a)

APPENDIX Share buy-back programme - Specification for April 14 – April 18, 2025

GENMAB A/S	15-Apr-2025	3:34:39 PM	27	1301.50	TQEX
GENMAB A/S	15-Apr-2025	3:34:39 PM	11	1301.50	TQEX
GENMAB A/S	15-Apr-2025	3:34:39 PM	34	1301.50	CEUX
GENMAB A/S	15-Apr-2025	3:34:39 PM	54	1301.50	CEUX
GENMAB A/S	15-Apr-2025	3:34:51 PM	2	1301.00	XCSE
GENMAB A/S	15-Apr-2025	3:34:59 PM	36	1302.00	CEUX
GENMAB A/S	15-Apr-2025	3:35:00 PM	12	1302.00	CEUX
GENMAB A/S	15-Apr-2025	3:35:00 PM	31	1302.00	CEUX
GENMAB A/S	15-Apr-2025	3:35:00 PM	13	1302.00	CEUX
GENMAB A/S	15-Apr-2025	3:35:04 PM	83	1301.00	XCSE
GENMAB A/S	15-Apr-2025	3:35:04 PM	35	1301.00	XCSE
GENMAB A/S	15-Apr-2025	3:35:04 PM	48	1301.50	XCSE
GENMAB A/S	15-Apr-2025	3:35:04 PM	31	1301.50	XCSE
GENMAB A/S	15-Apr-2025	3:35:04 PM	30	1301.00	AQEU
GENMAB A/S	15-Apr-2025	3:35:05 PM	15	1301.50	XCSE
GENMAB A/S	15-Apr-2025	3:35:05 PM	23	1301.50	XCSE
GENMAB A/S	15-Apr-2025	3:35:05 PM	16	1301.50	XCSE
GENMAB A/S	15-Apr-2025	3:35:05 PM	17	1301.50	XCSE
GENMAB A/S	15-Apr-2025	3:35:05 PM	35	1301.50	XCSE
GENMAB A/S	15-Apr-2025	3:35:05 PM	22	1301.50	XCSE
GENMAB A/S	15-Apr-2025	3:35:05 PM	46	1301.50	XCSE
GENMAB A/S	15-Apr-2025	3:35:05 PM	15	1301.50	XCSE
GENMAB A/S	15-Apr-2025	3:35:05 PM	17	1301.50	XCSE
GENMAB A/S	15-Apr-2025	3:35:05 PM	14	1301.50	XCSE
GENMAB A/S	15-Apr-2025	3:35:05 PM	14	1301.50	XCSE
GENMAB A/S	15-Apr-2025	3:35:05 PM	13	1301.50	XCSE
GENMAB A/S	15-Apr-2025	3:35:05 PM	46	1301.50	XCSE
GENMAB A/S	15-Apr-2025	3:35:05 PM	16	1301.50	XCSE
GENMAB A/S	15-Apr-2025	3:35:13 PM	85	1301.00	XCSE
GENMAB A/S	15-Apr-2025	3:35:13 PM	26	1301.00	AQEU
GENMAB A/S	15-Apr-2025	3:35:13 PM	32	1301.00	CEUX
GENMAB A/S	15-Apr-2025	3:35:33 PM	5	1300.00	XCSE
GENMAB A/S	15-Apr-2025	3:35:33 PM	15	1300.00	XCSE
GENMAB A/S	15-Apr-2025	3:35:33 PM	10	1300.00	XCSE
GENMAB A/S	15-Apr-2025	3:35:33 PM	5	1300.00	XCSE
GENMAB A/S	15-Apr-2025	3:35:33 PM	10	1300.00	XCSE
GENMAB A/S	15-Apr-2025	3:35:33 PM	5	1300.00	XCSE
GENMAB A/S	15-Apr-2025	3:35:33 PM	40	1300.00	XCSE
GENMAB A/S	15-Apr-2025	3:35:33 PM	38	1300.50	TQEX
GENMAB A/S	15-Apr-2025	3:35:33 PM	4	1299.50	TQEX
GENMAB A/S	15-Apr-2025	3:35:33 PM	2	1299.50	TQEX
GENMAB A/S	15-Apr-2025	3:35:33 PM	5	1299.50	TQEX
GENMAB A/S	15-Apr-2025	3:35:33 PM	26	1300.00	AQEU

115

Exhibit 99.1(a)

APPENDIX Share buy-back programme - Specification for April 14 – April 18, 2025

GENMAB A/S	15-Apr-2025	3:35:33 PM	90	1300.50	CEUX
GENMAB A/S	15-Apr-2025	3:35:50 PM	23	1299.50	TQEX
GENMAB A/S	15-Apr-2025	3:35:50 PM	20	1299.50	CEUX
GENMAB A/S	15-Apr-2025	3:35:50 PM	64	1299.50	CEUX
GENMAB A/S	15-Apr-2025	3:35:51 PM	90	1299.00	XCSE
GENMAB A/S	15-Apr-2025	3:36:02 PM	91	1297.50	XCSE
GENMAB A/S	15-Apr-2025	3:36:02 PM	87	1298.00	CEUX
GENMAB A/S	15-Apr-2025	3:36:03 PM	41	1296.50	XCSE
GENMAB A/S	15-Apr-2025	3:36:03 PM	50	1296.50	XCSE
GENMAB A/S	15-Apr-2025	3:36:03 PM	88	1297.00	CEUX
GENMAB A/S	15-Apr-2025	3:36:03 PM	23	1296.00	CEUX
GENMAB A/S	15-Apr-2025	3:36:40 PM	89	1298.50	XCSE
GENMAB A/S	15-Apr-2025	3:37:01 PM	90	1297.50	XCSE
GENMAB A/S	15-Apr-2025	3:37:01 PM	25	1298.00	TQEX
GENMAB A/S	15-Apr-2025	3:37:01 PM	11	1298.00	CEUX
GENMAB A/S	15-Apr-2025	3:37:01 PM	77	1298.00	CEUX
GENMAB A/S	15-Apr-2025	3:37:21 PM	86	1298.00	XCSE
GENMAB A/S	15-Apr-2025	3:38:28 PM	86	1299.00	CEUX
GENMAB A/S	15-Apr-2025	3:38:29 PM	86	1298.50	XCSE
GENMAB A/S	15-Apr-2025	3:38:29 PM	35	1299.00	XCSE
GENMAB A/S	15-Apr-2025	3:38:29 PM	24	1299.00	XCSE
GENMAB A/S	15-Apr-2025	3:38:29 PM	46	1299.00	XCSE
GENMAB A/S	15-Apr-2025	3:38:29 PM	9	1299.00	XCSE
GENMAB A/S	15-Apr-2025	3:38:29 PM	25	1298.50	AQEU
GENMAB A/S	15-Apr-2025	3:38:29 PM	90	1298.00	CEUX
GENMAB A/S	15-Apr-2025	3:38:30 PM	31	1298.50	XCSE
GENMAB A/S	15-Apr-2025	3:38:31 PM	54	1298.50	XCSE
GENMAB A/S	15-Apr-2025	3:39:01 PM	2	1299.00	XCSE
GENMAB A/S	15-Apr-2025	3:39:06 PM	85	1299.00	XCSE
GENMAB A/S	15-Apr-2025	3:39:06 PM	26	1299.50	AQEU
GENMAB A/S	15-Apr-2025	3:39:10 PM	2	1299.00	XCSE
GENMAB A/S	15-Apr-2025	3:39:33 PM	56	1299.00	XCSE
GENMAB A/S	15-Apr-2025	3:39:43 PM	15	1299.00	XCSE
GENMAB A/S	15-Apr-2025	3:39:43 PM	25	1299.00	XCSE
GENMAB A/S	15-Apr-2025	3:39:53 PM	15	1299.00	XCSE
GENMAB A/S	15-Apr-2025	3:39:53 PM	25	1299.00	XCSE
GENMAB A/S	15-Apr-2025	3:39:53 PM	2	1299.00	XCSE
GENMAB A/S	15-Apr-2025	3:39:53 PM	46	1299.00	XCSE
GENMAB A/S	15-Apr-2025	3:40:13 PM	32	1299.00	CEUX
GENMAB A/S	15-Apr-2025	3:40:31 PM	25	1299.00	CEUX
GENMAB A/S	15-Apr-2025	3:40:32 PM	26	1299.00	CEUX
GENMAB A/S	15-Apr-2025	3:40:43 PM	3	1299.00	CEUX
GENMAB A/S	15-Apr-2025	3:40:51 PM	80	1299.00	XCSE

116

Exhibit 99.1(a)

APPENDIX Share buy-back programme - Specification for April 14 – April 18, 2025

GENMAB A/S	15-Apr-2025	3:40:51 PM	7	1299.00	XCSE
GENMAB A/S	15-Apr-2025	3:40:52 PM	5	1299.00	AQEU
GENMAB A/S	15-Apr-2025	3:40:53 PM	30	1299.00	AQEU
GENMAB A/S	15-Apr-2025	3:40:56 PM	91	1297.50	XCSE
GENMAB A/S	15-Apr-2025	3:40:56 PM	84	1296.50	XCSE
GENMAB A/S	15-Apr-2025	3:40:56 PM	91	1295.50	XCSE
GENMAB A/S	15-Apr-2025	3:40:56 PM	91	1295.00	XCSE
GENMAB A/S	15-Apr-2025	3:40:56 PM	90	1294.00	XCSE
GENMAB A/S	15-Apr-2025	3:40:56 PM	91	1292.50	XCSE
GENMAB A/S	15-Apr-2025	3:40:56 PM	86	1291.00	XCSE
GENMAB A/S	15-Apr-2025	3:40:56 PM	27	1298.00	TQEX
GENMAB A/S	15-Apr-2025	3:40:56 PM	26	1296.50	TQEX
GENMAB A/S	15-Apr-2025	3:40:56 PM	33	1295.50	TQEX
GENMAB A/S	15-Apr-2025	3:40:56 PM	35	1298.00	AQEU
GENMAB A/S	15-Apr-2025	3:40:56 PM	25	1297.00	AQEU
GENMAB A/S	15-Apr-2025	3:40:56 PM	85	1298.50	CEUX
GENMAB A/S	15-Apr-2025	3:40:56 PM	85	1297.00	CEUX
GENMAB A/S	15-Apr-2025	3:40:56 PM	84	1295.50	CEUX
GENMAB A/S	15-Apr-2025	3:40:56 PM	66	1295.50	CEUX
GENMAB A/S	15-Apr-2025	3:40:56 PM	23	1295.50	CEUX
GENMAB A/S	15-Apr-2025	3:40:56 PM	86	1294.00	CEUX
GENMAB A/S	15-Apr-2025	3:40:56 PM	87	1292.50	CEUX
GENMAB A/S	15-Apr-2025	3:40:56 PM	28	1291.50	CEUX
GENMAB A/S	15-Apr-2025	3:40:57 PM	29	1293.00	XCSE
GENMAB A/S	15-Apr-2025	3:41:28 PM	49	1295.00	XCSE
GENMAB A/S	15-Apr-2025	3:41:28 PM	14	1294.50	CEUX
GENMAB A/S	15-Apr-2025	3:41:28 PM	20	1294.50	CEUX
GENMAB A/S	15-Apr-2025	3:41:30 PM	29	1294.00	XCSE
GENMAB A/S	15-Apr-2025	3:42:38 PM	91	1294.00	XCSE
GENMAB A/S	15-Apr-2025	3:42:38 PM	34	1294.00	TQEX
GENMAB A/S	15-Apr-2025	3:42:54 PM	68	1295.50	XCSE
GENMAB A/S	15-Apr-2025	3:42:54 PM	17	1295.50	XCSE
GENMAB A/S	15-Apr-2025	3:43:30 PM	87	1295.50	XCSE
GENMAB A/S	15-Apr-2025	3:43:51 PM	25	1295.00	TQEX
GENMAB A/S	15-Apr-2025	3:43:51 PM	27	1295.00	AQEU
GENMAB A/S	15-Apr-2025	3:43:51 PM	84	1295.00	CEUX
GENMAB A/S	15-Apr-2025	3:44:11 PM	1	1294.00	XCSE
GENMAB A/S	15-Apr-2025	3:44:11 PM	89	1294.50	CEUX
GENMAB A/S	15-Apr-2025	3:44:22 PM	91	1294.50	CEUX
GENMAB A/S	15-Apr-2025	3:44:31 PM	74	1294.00	XCSE
GENMAB A/S	15-Apr-2025	3:44:31 PM	12	1294.00	XCSE
GENMAB A/S	15-Apr-2025	3:44:31 PM	21	1294.00	TQEX
GENMAB A/S	15-Apr-2025	3:44:31 PM	12	1294.00	TQEX

117

Exhibit 99.1(a)

APPENDIX Share buy-back programme - Specification for April 14 – April 18, 2025

GENMAB A/S	15-Apr-2025	3:44:51 PM	27	1294.00	AQEU
GENMAB A/S	15-Apr-2025	3:44:51 PM	25	1293.50	CEUX
GENMAB A/S	15-Apr-2025	3:45:04 PM	30	1293.00	XCSE
GENMAB A/S	15-Apr-2025	3:45:36 PM	84	1293.50	CEUX
GENMAB A/S	15-Apr-2025	3:45:36 PM	3	1293.50	CEUX
GENMAB A/S	15-Apr-2025	3:45:45 PM	47	1293.50	XCSE
GENMAB A/S	15-Apr-2025	3:45:45 PM	46	1293.50	XCSE
GENMAB A/S	15-Apr-2025	3:45:45 PM	13	1293.50	XCSE
GENMAB A/S	15-Apr-2025	3:45:45 PM	86	1293.00	XCSE
GENMAB A/S	15-Apr-2025	3:45:46 PM	17	1293.50	XCSE
GENMAB A/S	15-Apr-2025	3:45:46 PM	26	1293.50	XCSE
GENMAB A/S	15-Apr-2025	3:45:46 PM	46	1293.50	XCSE
GENMAB A/S	15-Apr-2025	3:45:46 PM	17	1293.50	XCSE
GENMAB A/S	15-Apr-2025	3:45:46 PM	14	1293.50	XCSE
GENMAB A/S	15-Apr-2025	3:45:46 PM	26	1293.50	XCSE
GENMAB A/S	15-Apr-2025	3:45:46 PM	17	1293.50	XCSE
GENMAB A/S	15-Apr-2025	3:45:46 PM	46	1293.50	XCSE
GENMAB A/S	15-Apr-2025	3:46:07 PM	6	1293.00	XCSE
GENMAB A/S	15-Apr-2025	3:46:07 PM	2	1293.00	XCSE
GENMAB A/S	15-Apr-2025	3:46:07 PM	3	1293.00	XCSE
GENMAB A/S	15-Apr-2025	3:46:07 PM	77	1293.00	XCSE
GENMAB A/S	15-Apr-2025	3:46:07 PM	30	1293.50	AQEU
GENMAB A/S	15-Apr-2025	3:46:07 PM	88	1293.00	CEUX
GENMAB A/S	15-Apr-2025	3:46:19 PM	88	1293.00	XCSE
GENMAB A/S	15-Apr-2025	3:46:19 PM	3	1293.00	XCSE
GENMAB A/S	15-Apr-2025	3:46:19 PM	89	1293.00	CEUX
GENMAB A/S	15-Apr-2025	3:46:47 PM	16	1295.00	XCSE
GENMAB A/S	15-Apr-2025	3:46:47 PM	14	1295.00	XCSE
GENMAB A/S	15-Apr-2025	3:46:47 PM	14	1295.00	XCSE
GENMAB A/S	15-Apr-2025	3:46:47 PM	46	1295.00	XCSE
GENMAB A/S	15-Apr-2025	3:47:31 PM	28	1295.50	TQEX
GENMAB A/S	15-Apr-2025	3:47:31 PM	91	1295.50	CEUX
GENMAB A/S	15-Apr-2025	3:47:32 PM	21	1296.00	TQEX
GENMAB A/S	15-Apr-2025	3:47:32 PM	81	1296.00	CEUX
GENMAB A/S	15-Apr-2025	3:47:32 PM	7	1296.00	CEUX
GENMAB A/S	15-Apr-2025	3:48:16 PM	28	1297.00	TQEX
GENMAB A/S	15-Apr-2025	3:48:41 PM	86	1296.50	XCSE
GENMAB A/S	15-Apr-2025	3:48:41 PM	91	1296.50	CEUX
GENMAB A/S	15-Apr-2025	3:49:02 PM	14	1296.50	XCSE
GENMAB A/S	15-Apr-2025	3:49:02 PM	46	1296.50	XCSE
GENMAB A/S	15-Apr-2025	3:49:02 PM	21	1296.50	XCSE
GENMAB A/S	15-Apr-2025	3:49:02 PM	4	1296.00	TQEX
GENMAB A/S	15-Apr-2025	3:49:02 PM	34	1296.50	AQEU

118

Exhibit 99.1(a)

APPENDIX Share buy-back programme - Specification for April 14 – April 18, 2025

GENMAB A/S	15-Apr-2025	3:49:21 PM	2	1296.00	TQEX
GENMAB A/S	15-Apr-2025	3:49:21 PM	35	1296.50	AQEU
GENMAB A/S	15-Apr-2025	3:49:21 PM	86	1296.50	CEUX
GENMAB A/S	15-Apr-2025	3:49:38 PM	1	1295.50	CEUX
GENMAB A/S	15-Apr-2025	3:49:43 PM	2	1295.50	CEUX
GENMAB A/S	15-Apr-2025	3:49:44 PM	1	1295.50	CEUX
GENMAB A/S	15-Apr-2025	3:49:48 PM	1	1295.50	CEUX
GENMAB A/S	15-Apr-2025	3:49:48 PM	2	1295.50	CEUX
GENMAB A/S	15-Apr-2025	3:49:48 PM	81	1295.50	CEUX
GENMAB A/S	15-Apr-2025	3:49:51 PM	90	1295.00	XCSE
GENMAB A/S	15-Apr-2025	3:49:51 PM	42	1295.00	XCSE
GENMAB A/S	15-Apr-2025	3:49:51 PM	12	1295.00	XCSE
GENMAB A/S	15-Apr-2025	3:49:51 PM	25	1295.50	AQEU
GENMAB A/S	15-Apr-2025	3:49:52 PM	1	1295.50	CEUX
GENMAB A/S	15-Apr-2025	3:49:55 PM	46	1296.50	XCSE
GENMAB A/S	15-Apr-2025	3:49:58 PM	114	1296.50	XCSE
GENMAB A/S	15-Apr-2025	3:50:01 PM	86	1296.50	CEUX
GENMAB A/S	15-Apr-2025	3:50:02 PM	15	1296.50	XCSE
GENMAB A/S	15-Apr-2025	3:50:02 PM	25	1296.50	XCSE
GENMAB A/S	15-Apr-2025	3:50:35 PM	25	1297.00	TQEX
GENMAB A/S	15-Apr-2025	3:51:22 PM	41	1297.50	XCSE
GENMAB A/S	15-Apr-2025	3:51:22 PM	48	1297.50	XCSE
GENMAB A/S	15-Apr-2025	3:51:22 PM	3	1297.50	TQEX
GENMAB A/S	15-Apr-2025	3:51:22 PM	22	1297.50	TQEX
GENMAB A/S	15-Apr-2025	3:51:22 PM	88	1297.50	CEUX
GENMAB A/S	15-Apr-2025	3:51:37 PM	12	1297.50	XCSE
GENMAB A/S	15-Apr-2025	3:51:37 PM	18	1297.50	XCSE
GENMAB A/S	15-Apr-2025	3:52:21 PM	76	1298.00	XCSE
GENMAB A/S	15-Apr-2025	3:52:21 PM	9	1298.00	XCSE
GENMAB A/S	15-Apr-2025	3:52:21 PM	46	1298.00	XCSE
GENMAB A/S	15-Apr-2025	3:52:21 PM	38	1298.00	TQEX
GENMAB A/S	15-Apr-2025	3:52:21 PM	7	1298.00	AQEU
GENMAB A/S	15-Apr-2025	3:52:27 PM	50	1298.00	XCSE
GENMAB A/S	15-Apr-2025	3:52:27 PM	35	1298.00	XCSE
GENMAB A/S	15-Apr-2025	3:52:27 PM	22	1298.00	XCSE
GENMAB A/S	15-Apr-2025	3:52:27 PM	7	1298.00	XCSE
GENMAB A/S	15-Apr-2025	3:52:27 PM	39	1298.00	XCSE
GENMAB A/S	15-Apr-2025	3:52:27 PM	17	1298.00	XCSE
GENMAB A/S	15-Apr-2025	3:52:27 PM	14	1298.00	XCSE
GENMAB A/S	15-Apr-2025	3:52:27 PM	36	1298.00	AQEU
GENMAB A/S	15-Apr-2025	3:52:27 PM	89	1297.50	CEUX
GENMAB A/S	15-Apr-2025	3:52:28 PM	24	1297.00	XCSE
GENMAB A/S	15-Apr-2025	3:52:28 PM	24	1297.00	XCSE

119

Exhibit 99.1(a)

APPENDIX Share buy-back programme - Specification for April 14 – April 18, 2025

GENMAB A/S	15-Apr-2025	3:52:28 PM	15	1297.00	XCSE
GENMAB A/S	15-Apr-2025	3:52:28 PM	25	1297.00	XCSE
GENMAB A/S	15-Apr-2025	3:52:28 PM	16	1297.00	TQEX
GENMAB A/S	15-Apr-2025	3:52:28 PM	10	1297.00	TQEX
GENMAB A/S	15-Apr-2025	3:52:28 PM	5	1297.00	TQEX
GENMAB A/S	15-Apr-2025	3:52:28 PM	25	1297.00	AQEU
GENMAB A/S	15-Apr-2025	3:52:28 PM	1	1297.50	CEUX
GENMAB A/S	15-Apr-2025	3:52:28 PM	90	1297.50	CEUX
GENMAB A/S	15-Apr-2025	3:52:30 PM	46	1297.00	XCSE
GENMAB A/S	15-Apr-2025	3:52:30 PM	17	1297.00	XCSE
GENMAB A/S	15-Apr-2025	3:52:30 PM	35	1297.00	XCSE
GENMAB A/S	15-Apr-2025	3:52:30 PM	16	1297.00	XCSE
GENMAB A/S	15-Apr-2025	3:52:30 PM	16	1297.00	XCSE
GENMAB A/S	15-Apr-2025	3:52:30 PM	59	1297.00	XCSE
GENMAB A/S	15-Apr-2025	3:52:30 PM	16	1297.00	XCSE
GENMAB A/S	15-Apr-2025	3:52:30 PM	15	1297.00	XCSE
GENMAB A/S	15-Apr-2025	3:52:30 PM	1	1297.00	AQEU
GENMAB A/S	15-Apr-2025	3:52:30 PM	12	1296.50	CEUX
GENMAB A/S	15-Apr-2025	3:52:30 PM	31	1296.50	CEUX
GENMAB A/S	15-Apr-2025	3:52:31 PM	14	1297.00	XCSE
GENMAB A/S	15-Apr-2025	3:52:31 PM	23	1297.00	XCSE
GENMAB A/S	15-Apr-2025	3:52:32 PM	87	1297.00	CEUX
GENMAB A/S	15-Apr-2025	3:52:35 PM	35	1297.00	XCSE
GENMAB A/S	15-Apr-2025	3:52:35 PM	28	1297.00	XCSE
GENMAB A/S	15-Apr-2025	3:52:35 PM	35	1297.00	XCSE
GENMAB A/S	15-Apr-2025	3:52:35 PM	15	1297.00	XCSE
GENMAB A/S	15-Apr-2025	3:52:35 PM	1	1297.00	XCSE
GENMAB A/S	15-Apr-2025	3:52:35 PM	50	1296.50	XCSE
GENMAB A/S	15-Apr-2025	3:52:35 PM	17	1296.50	XCSE
GENMAB A/S	15-Apr-2025	3:52:35 PM	28	1296.50	XCSE
GENMAB A/S	15-Apr-2025	3:52:35 PM	15	1297.00	XCSE
GENMAB A/S	15-Apr-2025	3:52:35 PM	4	1297.00	XCSE
GENMAB A/S	15-Apr-2025	3:52:36 PM	17	1296.50	XCSE
GENMAB A/S	15-Apr-2025	3:52:36 PM	28	1296.50	XCSE
GENMAB A/S	15-Apr-2025	3:52:36 PM	14	1296.50	XCSE
GENMAB A/S	15-Apr-2025	3:52:36 PM	55	1296.50	XCSE
GENMAB A/S	15-Apr-2025	3:52:36 PM	37	1296.50	XCSE
GENMAB A/S	15-Apr-2025	3:52:52 PM	14	1296.50	XCSE
GENMAB A/S	15-Apr-2025	3:53:05 PM	90	1296.00	XCSE
GENMAB A/S	15-Apr-2025	3:53:05 PM	35	1295.50	XCSE
GENMAB A/S	15-Apr-2025	3:53:05 PM	46	1296.00	XCSE
GENMAB A/S	15-Apr-2025	3:53:05 PM	33	1296.00	XCSE
GENMAB A/S	15-Apr-2025	3:53:05 PM	38	1296.00	TQEX

120

Exhibit 99.1(a)

APPENDIX Share buy-back programme - Specification for April 14 – April 18, 2025

GENMAB A/S	15-Apr-2025	3:53:05 PM	30	1296.00	AQEU
GENMAB A/S	15-Apr-2025	3:53:05 PM	11	1296.50	CEUX
GENMAB A/S	15-Apr-2025	3:53:05 PM	74	1296.50	CEUX
GENMAB A/S	15-Apr-2025	3:53:05 PM	88	1295.50	CEUX
GENMAB A/S	15-Apr-2025	3:53:06 PM	29	1295.00	CEUX
GENMAB A/S	15-Apr-2025	3:53:40 PM	18	1295.50	XCSE
GENMAB A/S	15-Apr-2025	3:53:51 PM	91	1296.50	XCSE
GENMAB A/S	15-Apr-2025	3:53:52 PM	49	1296.50	XCSE
GENMAB A/S	15-Apr-2025	3:53:52 PM	46	1296.50	XCSE
GENMAB A/S	15-Apr-2025	3:53:52 PM	10	1296.50	XCSE
GENMAB A/S	15-Apr-2025	3:53:52 PM	34	1296.50	AQEU
GENMAB A/S	15-Apr-2025	3:53:54 PM	41	1296.00	CEUX
GENMAB A/S	15-Apr-2025	3:53:54 PM	5	1296.00	CEUX
GENMAB A/S	15-Apr-2025	3:54:01 PM	10	1295.50	XCSE
GENMAB A/S	15-Apr-2025	3:54:18 PM	22	1296.50	TQEX
GENMAB A/S	15-Apr-2025	3:54:18 PM	7	1296.50	TQEX
GENMAB A/S	15-Apr-2025	3:54:21 PM	1	1296.00	CEUX
GENMAB A/S	15-Apr-2025	3:54:47 PM	87	1296.50	XCSE
GENMAB A/S	15-Apr-2025	3:55:24 PM	26	1296.50	TQEX
GENMAB A/S	15-Apr-2025	3:55:27 PM	25	1296.50	XCSE
GENMAB A/S	15-Apr-2025	3:55:30 PM	35	1297.00	XCSE
GENMAB A/S	15-Apr-2025	3:55:30 PM	22	1297.00	XCSE
GENMAB A/S	15-Apr-2025	3:55:30 PM	15	1297.00	XCSE
GENMAB A/S	15-Apr-2025	3:55:30 PM	42	1297.00	XCSE
GENMAB A/S	15-Apr-2025	3:55:30 PM	89	1297.00	CEUX
GENMAB A/S	15-Apr-2025	3:55:31 PM	17	1297.00	XCSE
GENMAB A/S	15-Apr-2025	3:55:31 PM	46	1297.00	XCSE
GENMAB A/S	15-Apr-2025	3:55:31 PM	22	1297.00	XCSE
GENMAB A/S	15-Apr-2025	3:55:31 PM	60	1296.50	XCSE
GENMAB A/S	15-Apr-2025	3:56:01 PM	87	1296.50	XCSE
GENMAB A/S	15-Apr-2025	3:56:04 PM	49	1296.50	XCSE
GENMAB A/S	15-Apr-2025	3:56:04 PM	35	1296.50	XCSE
GENMAB A/S	15-Apr-2025	3:56:04 PM	16	1296.50	XCSE
GENMAB A/S	15-Apr-2025	3:56:04 PM	85	1296.50	XCSE
GENMAB A/S	15-Apr-2025	3:56:25 PM	49	1296.50	XCSE
GENMAB A/S	15-Apr-2025	3:56:33 PM	67	1296.50	XCSE
GENMAB A/S	15-Apr-2025	3:56:33 PM	21	1296.50	XCSE
GENMAB A/S	15-Apr-2025	3:56:53 PM	48	1296.50	XCSE
GENMAB A/S	15-Apr-2025	3:56:53 PM	29	1296.50	XCSE
GENMAB A/S	15-Apr-2025	3:56:53 PM	27	1296.00	TQEX
GENMAB A/S	15-Apr-2025	3:56:53 PM	14	1296.00	AQEU
GENMAB A/S	15-Apr-2025	3:56:53 PM	18	1296.00	AQEU
GENMAB A/S	15-Apr-2025	3:56:53 PM	5	1296.00	CEUX

121

Exhibit 99.1(a)

APPENDIX Share buy-back programme - Specification for April 14 – April 18, 2025

GENMAB A/S	15-Apr-2025	3:56:53 PM	79	1296.00	CEUX
GENMAB A/S	15-Apr-2025	3:57:03 PM	13	1296.50	XCSE
GENMAB A/S	15-Apr-2025	3:57:03 PM	7	1296.50	XCSE
GENMAB A/S	15-Apr-2025	3:57:03 PM	59	1296.50	XCSE
GENMAB A/S	15-Apr-2025	3:57:03 PM	11	1296.50	XCSE
GENMAB A/S	15-Apr-2025	3:57:17 PM	27	1296.00	TQEX
GENMAB A/S	15-Apr-2025	3:57:17 PM	3	1296.00	TQEX
GENMAB A/S	15-Apr-2025	3:57:17 PM	88	1296.00	CEUX
GENMAB A/S	15-Apr-2025	3:57:21 PM	60	1295.50	XCSE
GENMAB A/S	15-Apr-2025	3:57:51 PM	5	1294.50	XCSE
GENMAB A/S	15-Apr-2025	3:57:51 PM	31	1295.00	AQEU
GENMAB A/S	15-Apr-2025	3:57:51 PM	53	1295.00	CEUX
GENMAB A/S	15-Apr-2025	3:58:15 PM	35	1295.00	XCSE
GENMAB A/S	15-Apr-2025	3:58:15 PM	28	1295.00	XCSE
GENMAB A/S	15-Apr-2025	3:58:15 PM	46	1295.00	XCSE
GENMAB A/S	15-Apr-2025	3:58:15 PM	5	1295.00	XCSE
GENMAB A/S	15-Apr-2025	3:58:15 PM	34	1294.50	XCSE
GENMAB A/S	15-Apr-2025	3:58:21 PM	48	1294.50	XCSE
GENMAB A/S	15-Apr-2025	3:58:21 PM	27	1294.50	TQEX
GENMAB A/S	15-Apr-2025	3:58:42 PM	85	1294.50	CEUX
GENMAB A/S	15-Apr-2025	3:58:44 PM	48	1294.50	XCSE
GENMAB A/S	15-Apr-2025	3:58:44 PM	35	1294.50	XCSE
GENMAB A/S	15-Apr-2025	3:58:44 PM	15	1294.50	XCSE
GENMAB A/S	15-Apr-2025	3:58:44 PM	16	1294.50	XCSE
GENMAB A/S	15-Apr-2025	3:58:46 PM	25	1294.00	AQEU
GENMAB A/S	15-Apr-2025	3:58:54 PM	35	1294.00	XCSE
GENMAB A/S	15-Apr-2025	3:58:54 PM	17	1294.00	XCSE
GENMAB A/S	15-Apr-2025	3:58:54 PM	14	1294.00	XCSE
GENMAB A/S	15-Apr-2025	3:58:54 PM	9	1294.50	XCSE
GENMAB A/S	15-Apr-2025	3:58:54 PM	27	1294.50	XCSE
GENMAB A/S	15-Apr-2025	3:58:54 PM	12	1294.50	XCSE
GENMAB A/S	15-Apr-2025	3:58:54 PM	24	1293.50	XCSE
GENMAB A/S	15-Apr-2025	3:58:54 PM	32	1294.00	AQEU
GENMAB A/S	15-Apr-2025	3:58:54 PM	32	1293.50	CEUX
GENMAB A/S	15-Apr-2025	3:58:54 PM	31	1293.50	CEUX
GENMAB A/S	15-Apr-2025	3:59:08 PM	61	1293.50	XCSE
GENMAB A/S	15-Apr-2025	3:59:08 PM	28	1293.50	CEUX
GENMAB A/S	15-Apr-2025	3:59:20 PM	87	1293.00	XCSE
GENMAB A/S	15-Apr-2025	3:59:20 PM	31	1292.50	TQEX
GENMAB A/S	15-Apr-2025	3:59:20 PM	90	1292.50	CEUX
GENMAB A/S	15-Apr-2025	3:59:21 PM	25	1292.50	AQEU
GENMAB A/S	15-Apr-2025	3:59:41 PM	42	1293.00	XCSE
GENMAB A/S	15-Apr-2025	3:59:46 PM	36	1292.50	XCSE

122

Exhibit 99.1(a)

APPENDIX Share buy-back programme - Specification for April 14 – April 18, 2025

GENMAB A/S	15-Apr-2025	3:59:46 PM	90	1292.00	XCSE
GENMAB A/S	15-Apr-2025	3:59:46 PM	82	1292.50	CEUX
GENMAB A/S	15-Apr-2025	3:59:46 PM	7	1292.50	CEUX
GENMAB A/S	15-Apr-2025	3:59:59 PM	64	1291.50	XCSE
GENMAB A/S	15-Apr-2025	3:59:59 PM	27	1291.50	XCSE
GENMAB A/S	15-Apr-2025	4:00:14 PM	85	1291.50	XCSE
GENMAB A/S	15-Apr-2025	4:00:21 PM	89	1291.00	CEUX
GENMAB A/S	15-Apr-2025	4:00:48 PM	90	1292.50	XCSE
GENMAB A/S	15-Apr-2025	4:00:58 PM	37	1292.50	AQEU
GENMAB A/S	15-Apr-2025	4:01:11 PM	31	1292.00	XCSE
GENMAB A/S	15-Apr-2025	4:01:11 PM	80	1292.00	CEUX
GENMAB A/S	15-Apr-2025	4:01:11 PM	4	1292.00	CEUX
GENMAB A/S	15-Apr-2025	4:01:12 PM	71	1291.50	XCSE
GENMAB A/S	15-Apr-2025	4:01:12 PM	14	1291.50	XCSE
GENMAB A/S	15-Apr-2025	4:01:18 PM	20	1291.00	TQEX
GENMAB A/S	15-Apr-2025	4:01:18 PM	17	1291.00	TQEX
GENMAB A/S	15-Apr-2025	4:01:18 PM	84	1291.00	CEUX
GENMAB A/S	15-Apr-2025	4:01:19 PM	84	1290.50	XCSE
GENMAB A/S	15-Apr-2025	4:01:28 PM	85	1290.50	XCSE
GENMAB A/S	15-Apr-2025	4:01:45 PM	77	1290.00	CEUX
GENMAB A/S	15-Apr-2025	4:01:45 PM	7	1290.00	CEUX
GENMAB A/S	15-Apr-2025	4:02:00 PM	87	1289.00	XCSE
GENMAB A/S	15-Apr-2025	4:02:00 PM	85	1288.00	XCSE
GENMAB A/S	15-Apr-2025	4:02:00 PM	88	1288.50	CEUX
GENMAB A/S	15-Apr-2025	4:02:14 PM	86	1289.00	XCSE
GENMAB A/S	15-Apr-2025	4:02:14 PM	46	1288.50	CEUX
GENMAB A/S	15-Apr-2025	4:02:24 PM	72	1289.00	XCSE
GENMAB A/S	15-Apr-2025	4:02:24 PM	52	1288.50	CEUX
GENMAB A/S	15-Apr-2025	4:02:24 PM	25	1288.50	AQEU
GENMAB A/S	15-Apr-2025	4:02:57 PM	27	1288.50	CEUX
GENMAB A/S	15-Apr-2025	4:03:00 PM	81	1289.50	CEUX
GENMAB A/S	15-Apr-2025	4:03:20 PM	15	1290.00	XCSE
GENMAB A/S	15-Apr-2025	4:03:20 PM	73	1290.00	XCSE
GENMAB A/S	15-Apr-2025	4:03:20 PM	19	1290.00	TQEX
GENMAB A/S	15-Apr-2025	4:03:20 PM	16	1290.00	TQEX
GENMAB A/S	15-Apr-2025	4:03:23 PM	31	1289.50	CEUX
GENMAB A/S	15-Apr-2025	4:03:23 PM	25	1289.50	AQEU
GENMAB A/S	15-Apr-2025	4:03:24 PM	88	1289.00	XCSE
GENMAB A/S	15-Apr-2025	4:03:24 PM	28	1289.00	TQEX
GENMAB A/S	15-Apr-2025	4:03:24 PM	8	1289.00	TQEX
GENMAB A/S	15-Apr-2025	4:03:26 PM	86	1288.50	CEUX
GENMAB A/S	15-Apr-2025	4:03:26 PM	2	1288.50	AQEU
GENMAB A/S	15-Apr-2025	4:03:53 PM	87	1288.00	XCSE

123

Exhibit 99.1(a)

APPENDIX Share buy-back programme - Specification for April 14 – April 18, 2025

GENMAB A/S	15-Apr-2025	4:03:53 PM	37	1287.50	CEUX
GENMAB A/S	15-Apr-2025	4:03:53 PM	15	1287.50	CEUX
GENMAB A/S	15-Apr-2025	4:04:13 PM	44	1288.00	XCSE
GENMAB A/S	15-Apr-2025	4:04:17 PM	22	1287.50	CEUX
GENMAB A/S	15-Apr-2025	4:04:17 PM	14	1287.50	CEUX
GENMAB A/S	15-Apr-2025	4:04:17 PM	34	1288.00	AQEU
GENMAB A/S	15-Apr-2025	4:04:22 PM	88	1287.50	XCSE
GENMAB A/S	15-Apr-2025	4:04:22 PM	36	1287.50	XCSE
GENMAB A/S	15-Apr-2025	4:04:34 PM	87	1287.50	XCSE
GENMAB A/S	15-Apr-2025	4:04:34 PM	2	1287.50	CEUX
GENMAB A/S	15-Apr-2025	4:04:34 PM	26	1287.50	CEUX
GENMAB A/S	15-Apr-2025	4:04:35 PM	36	1287.50	CEUX
GENMAB A/S	15-Apr-2025	4:05:01 PM	87	1286.50	XCSE
GENMAB A/S	15-Apr-2025	4:05:13 PM	27	1286.50	TQEX
GENMAB A/S	15-Apr-2025	4:05:13 PM	11	1286.50	TQEX
GENMAB A/S	15-Apr-2025	4:05:22 PM	44	1286.00	CEUX
GENMAB A/S	15-Apr-2025	4:05:23 PM	69	1285.50	XCSE
GENMAB A/S	15-Apr-2025	4:05:23 PM	19	1285.50	XCSE
GENMAB A/S	15-Apr-2025	4:05:37 PM	50	1285.00	XCSE
GENMAB A/S	15-Apr-2025	4:05:37 PM	39	1285.00	XCSE
GENMAB A/S	15-Apr-2025	4:05:37 PM	27	1285.00	CEUX
GENMAB A/S	15-Apr-2025	4:06:29 PM	35	1287.00	XCSE
GENMAB A/S	15-Apr-2025	4:06:29 PM	29	1287.00	XCSE
GENMAB A/S	15-Apr-2025	4:06:29 PM	46	1287.00	XCSE
GENMAB A/S	15-Apr-2025	4:06:30 PM	85	1287.00	CEUX
GENMAB A/S	15-Apr-2025	4:06:31 PM	100	1287.00	XCSE
GENMAB A/S	15-Apr-2025	4:06:46 PM	36	1288.50	TQEX
GENMAB A/S	15-Apr-2025	4:07:01 PM	89	1288.00	XCSE
GENMAB A/S	15-Apr-2025	4:07:01 PM	77	1288.00	CEUX
GENMAB A/S	15-Apr-2025	4:07:02 PM	32	1288.00	AQEU
GENMAB A/S	15-Apr-2025	4:07:31 PM	89	1287.00	XCSE
GENMAB A/S	15-Apr-2025	4:07:31 PM	33	1287.50	XCSE
GENMAB A/S	15-Apr-2025	4:08:20 PM	46	1288.00	XCSE
GENMAB A/S	15-Apr-2025	4:08:20 PM	29	1288.00	XCSE
GENMAB A/S	15-Apr-2025	4:08:20 PM	52	1287.50	XCSE
GENMAB A/S	15-Apr-2025	4:08:20 PM	32	1288.00	CEUX
GENMAB A/S	15-Apr-2025	4:08:20 PM	36	1288.00	AQEU
GENMAB A/S	15-Apr-2025	4:08:38 PM	27	1288.00	CEUX
GENMAB A/S	15-Apr-2025	4:08:51 PM	84	1287.50	XCSE
GENMAB A/S	15-Apr-2025	4:08:53 PM	32	1288.00	CEUX
GENMAB A/S	15-Apr-2025	4:09:02 PM	35	1288.50	XCSE
GENMAB A/S	15-Apr-2025	4:09:02 PM	13	1288.50	XCSE
GENMAB A/S	15-Apr-2025	4:09:02 PM	32	1288.50	CEUX

124

Exhibit 99.1(a)

APPENDIX Share buy-back programme - Specification for April 14 – April 18, 2025

GENMAB A/S	15-Apr-2025	4:09:03 PM	35	1288.50	XCSE
GENMAB A/S	15-Apr-2025	4:09:03 PM	28	1288.50	XCSE
GENMAB A/S	15-Apr-2025	4:09:03 PM	46	1288.50	XCSE
GENMAB A/S	15-Apr-2025	4:09:03 PM	40	1288.00	TQEX
GENMAB A/S	15-Apr-2025	4:09:03 PM	66	1288.00	CEUX
GENMAB A/S	15-Apr-2025	4:09:03 PM	21	1288.00	CEUX
GENMAB A/S	15-Apr-2025	4:09:03 PM	42	1288.00	AQEU
GENMAB A/S	15-Apr-2025	4:09:15 PM	35	1289.00	XCSE
GENMAB A/S	15-Apr-2025	4:09:15 PM	15	1289.00	XCSE
GENMAB A/S	15-Apr-2025	4:09:15 PM	46	1289.00	XCSE
GENMAB A/S	15-Apr-2025	4:09:33 PM	49	1289.50	XCSE
GENMAB A/S	15-Apr-2025	4:09:33 PM	35	1289.50	XCSE
GENMAB A/S	15-Apr-2025	4:09:33 PM	16	1289.50	XCSE
GENMAB A/S	15-Apr-2025	4:09:50 PM	50	1289.50	XCSE
GENMAB A/S	15-Apr-2025	4:09:50 PM	86	1289.50	XCSE
GENMAB A/S	15-Apr-2025	4:09:50 PM	87	1289.00	CEUX
GENMAB A/S	15-Apr-2025	4:09:50 PM	2	1289.50	CEUX
GENMAB A/S	15-Apr-2025	4:09:50 PM	3	1289.50	CEUX
GENMAB A/S	15-Apr-2025	4:09:50 PM	5	1289.50	CEUX
GENMAB A/S	15-Apr-2025	4:09:50 PM	15	1289.50	CEUX
GENMAB A/S	15-Apr-2025	4:09:50 PM	10	1289.50	CEUX
GENMAB A/S	15-Apr-2025	4:09:50 PM	2	1289.50	CEUX
GENMAB A/S	15-Apr-2025	4:09:50 PM	7	1289.50	CEUX
GENMAB A/S	15-Apr-2025	4:09:50 PM	2	1289.50	CEUX
GENMAB A/S	15-Apr-2025	4:09:50 PM	24	1289.50	CEUX
GENMAB A/S	15-Apr-2025	4:09:50 PM	7	1289.50	CEUX
GENMAB A/S	15-Apr-2025	4:09:50 PM	3	1289.50	AQEU
GENMAB A/S	15-Apr-2025	4:09:56 PM	90	1290.50	CEUX
GENMAB A/S	15-Apr-2025	4:10:22 PM	16	1292.50	XCSE
GENMAB A/S	15-Apr-2025	4:10:22 PM	34	1292.50	XCSE
GENMAB A/S	15-Apr-2025	4:10:22 PM	6	1292.00	CEUX
GENMAB A/S	15-Apr-2025	4:10:22 PM	18	1292.00	CEUX
GENMAB A/S	15-Apr-2025	4:10:22 PM	9	1292.00	CEUX
GENMAB A/S	15-Apr-2025	4:10:22 PM	5	1292.00	CEUX
GENMAB A/S	15-Apr-2025	4:10:22 PM	7	1292.00	CEUX
GENMAB A/S	15-Apr-2025	4:10:22 PM	19	1292.00	CEUX
GENMAB A/S	15-Apr-2025	4:10:22 PM	2	1292.00	CEUX
GENMAB A/S	15-Apr-2025	4:10:22 PM	2	1292.00	CEUX
GENMAB A/S	15-Apr-2025	4:10:22 PM	9	1292.00	CEUX
GENMAB A/S	15-Apr-2025	4:10:23 PM	15	1292.50	XCSE
GENMAB A/S	15-Apr-2025	4:10:23 PM	10	1292.50	XCSE
GENMAB A/S	15-Apr-2025	4:10:23 PM	89	1292.00	XCSE
GENMAB A/S	15-Apr-2025	4:10:51 PM	48	1292.00	XCSE

125

Exhibit 99.1(a)

APPENDIX Share buy-back programme - Specification for April 14 – April 18, 2025

GENMAB A/S	15-Apr-2025	4:10:51 PM	15	1292.00	XCSE
GENMAB A/S	15-Apr-2025	4:10:51 PM	62	1292.00	CEUX
GENMAB A/S	15-Apr-2025	4:11:04 PM	14	1292.00	XCSE
GENMAB A/S	15-Apr-2025	4:11:07 PM	2	1292.50	TQEX
GENMAB A/S	15-Apr-2025	4:11:07 PM	3	1292.50	TQEX
GENMAB A/S	15-Apr-2025	4:11:26 PM	64	1293.00	XCSE
GENMAB A/S	15-Apr-2025	4:11:26 PM	26	1293.00	XCSE
GENMAB A/S	15-Apr-2025	4:11:26 PM	4	1292.50	TQEX
GENMAB A/S	15-Apr-2025	4:11:26 PM	24	1292.50	TQEX
GENMAB A/S	15-Apr-2025	4:11:26 PM	24	1292.50	CEUX
GENMAB A/S	15-Apr-2025	4:11:26 PM	8	1292.50	CEUX
GENMAB A/S	15-Apr-2025	4:11:26 PM	2	1292.50	CEUX
GENMAB A/S	15-Apr-2025	4:11:26 PM	25	1292.50	CEUX
GENMAB A/S	15-Apr-2025	4:11:26 PM	3	1292.50	AQEU
GENMAB A/S	15-Apr-2025	4:11:26 PM	34	1292.50	AQEU
GENMAB A/S	15-Apr-2025	4:11:51 PM	14	1293.50	XCSE
GENMAB A/S	15-Apr-2025	4:11:51 PM	16	1293.50	XCSE
GENMAB A/S	15-Apr-2025	4:11:52 PM	18	1293.50	XCSE
GENMAB A/S	15-Apr-2025	4:11:52 PM	14	1293.50	XCSE
GENMAB A/S	15-Apr-2025	4:11:52 PM	18	1293.50	XCSE
GENMAB A/S	15-Apr-2025	4:11:52 PM	14	1293.50	XCSE
GENMAB A/S	15-Apr-2025	4:12:11 PM	85	1293.00	XCSE
GENMAB A/S	15-Apr-2025	4:12:11 PM	70	1293.00	XCSE
GENMAB A/S	15-Apr-2025	4:12:11 PM	28	1293.00	XCSE
GENMAB A/S	15-Apr-2025	4:12:11 PM	16	1293.00	XCSE
GENMAB A/S	15-Apr-2025	4:12:11 PM	27	1292.00	TQEX
GENMAB A/S	15-Apr-2025	4:12:11 PM	81	1292.50	CEUX
GENMAB A/S	15-Apr-2025	4:12:11 PM	42	1293.00	AQEU
GENMAB A/S	15-Apr-2025	4:12:12 PM	64	1292.00	XCSE
GENMAB A/S	15-Apr-2025	4:12:12 PM	20	1292.00	XCSE
GENMAB A/S	15-Apr-2025	4:12:30 PM	89	1292.50	XCSE
GENMAB A/S	15-Apr-2025	4:12:30 PM	76	1292.50	CEUX
GENMAB A/S	15-Apr-2025	4:12:49 PM	59	1292.50	XCSE
GENMAB A/S	15-Apr-2025	4:12:49 PM	42	1292.50	TQEX
GENMAB A/S	15-Apr-2025	4:12:49 PM	54	1292.50	CEUX
GENMAB A/S	15-Apr-2025	4:13:27 PM	15	1293.00	XCSE
GENMAB A/S	15-Apr-2025	4:13:27 PM	2	1293.00	XCSE
GENMAB A/S	15-Apr-2025	4:13:27 PM	8	1293.00	XCSE
GENMAB A/S	15-Apr-2025	4:13:27 PM	3	1292.50	XCSE
GENMAB A/S	15-Apr-2025	4:13:27 PM	4	1292.50	XCSE
GENMAB A/S	15-Apr-2025	4:13:27 PM	12	1292.50	XCSE
GENMAB A/S	15-Apr-2025	4:13:28 PM	16	1293.00	CEUX
GENMAB A/S	15-Apr-2025	4:13:28 PM	10	1293.00	CEUX

126

Exhibit 99.1(a)

APPENDIX Share buy-back programme - Specification for April 14 – April 18, 2025

GENMAB A/S	15-Apr-2025	4:13:28 PM	20	1293.00	CEUX
GENMAB A/S	15-Apr-2025	4:13:28 PM	10	1293.00	CEUX
GENMAB A/S	15-Apr-2025	4:13:28 PM	10	1293.00	CEUX
GENMAB A/S	15-Apr-2025	4:13:28 PM	10	1293.00	CEUX
GENMAB A/S	15-Apr-2025	4:13:28 PM	6	1293.00	CEUX
GENMAB A/S	15-Apr-2025	4:13:28 PM	3	1293.00	CEUX
GENMAB A/S	15-Apr-2025	4:13:43 PM	17	1293.50	XCSE
GENMAB A/S	15-Apr-2025	4:13:43 PM	14	1293.50	XCSE
GENMAB A/S	15-Apr-2025	4:13:43 PM	20	1293.50	XCSE
GENMAB A/S	15-Apr-2025	4:13:43 PM	35	1293.50	XCSE
GENMAB A/S	15-Apr-2025	4:13:43 PM	28	1293.50	XCSE
GENMAB A/S	15-Apr-2025	4:13:45 PM	60	1292.50	XCSE
GENMAB A/S	15-Apr-2025	4:13:45 PM	34	1293.00	CEUX
GENMAB A/S	15-Apr-2025	4:14:07 PM	65	1291.50	CEUX
GENMAB A/S	15-Apr-2025	4:14:12 PM	9	1291.00	XCSE
GENMAB A/S	15-Apr-2025	4:14:12 PM	75	1291.00	XCSE
GENMAB A/S	15-Apr-2025	4:14:19 PM	57	1290.50	CEUX
GENMAB A/S	15-Apr-2025	4:14:24 PM	6	1290.50	XCSE
GENMAB A/S	15-Apr-2025	4:14:24 PM	20	1290.50	XCSE
GENMAB A/S	15-Apr-2025	4:14:24 PM	20	1290.50	XCSE
GENMAB A/S	15-Apr-2025	4:14:24 PM	9	1290.50	XCSE
GENMAB A/S	15-Apr-2025	4:14:24 PM	33	1290.50	XCSE
GENMAB A/S	15-Apr-2025	4:14:34 PM	3	1290.50	TQEX
GENMAB A/S	15-Apr-2025	4:14:41 PM	42	1290.50	XCSE
GENMAB A/S	15-Apr-2025	4:14:41 PM	32	1290.50	XCSE
GENMAB A/S	15-Apr-2025	4:14:41 PM	23	1290.50	CEUX
GENMAB A/S	15-Apr-2025	4:14:41 PM	8	1290.50	CEUX
GENMAB A/S	15-Apr-2025	4:14:46 PM	31	1290.00	AQEU
GENMAB A/S	15-Apr-2025	4:14:54 PM	91	1289.50	XCSE
GENMAB A/S	15-Apr-2025	4:14:54 PM	37	1289.50	CEUX
GENMAB A/S	15-Apr-2025	4:15:24 PM	79	1289.00	XCSE
GENMAB A/S	15-Apr-2025	4:15:34 PM	28	1289.00	CEUX
GENMAB A/S	15-Apr-2025	4:15:51 PM	2	1289.50	XCSE
GENMAB A/S	15-Apr-2025	4:15:51 PM	3	1289.50	XCSE
GENMAB A/S	15-Apr-2025	4:15:51 PM	7	1289.50	XCSE
GENMAB A/S	15-Apr-2025	4:15:51 PM	8	1289.50	XCSE
GENMAB A/S	15-Apr-2025	4:15:51 PM	65	1289.50	XCSE
GENMAB A/S	15-Apr-2025	4:15:51 PM	10	1289.00	TQEX
GENMAB A/S	15-Apr-2025	4:15:51 PM	24	1289.00	TQEX
GENMAB A/S	15-Apr-2025	4:15:51 PM	5	1289.50	CEUX
GENMAB A/S	15-Apr-2025	4:15:51 PM	10	1289.50	CEUX
GENMAB A/S	15-Apr-2025	4:15:51 PM	40	1289.50	CEUX
GENMAB A/S	15-Apr-2025	4:15:51 PM	10	1289.50	CEUX

127

Exhibit 99.1(a)

APPENDIX Share buy-back programme - Specification for April 14 – April 18, 2025

GENMAB A/S	15-Apr-2025	4:15:51 PM	5	1289.50	CEUX
GENMAB A/S	15-Apr-2025	4:15:51 PM	3	1289.50	CEUX
GENMAB A/S	15-Apr-2025	4:16:25 PM	2	1290.50	CEUX
GENMAB A/S	15-Apr-2025	4:16:25 PM	68	1290.50	CEUX
GENMAB A/S	15-Apr-2025	4:16:30 PM	114	1291.00	XCSE
GENMAB A/S	15-Apr-2025	4:16:32 PM	4	1290.50	CEUX
GENMAB A/S	15-Apr-2025	4:16:32 PM	7	1290.50	CEUX
GENMAB A/S	15-Apr-2025	4:16:32 PM	10	1290.50	CEUX
GENMAB A/S	15-Apr-2025	4:16:32 PM	3	1291.00	AQEU
GENMAB A/S	15-Apr-2025	4:16:32 PM	5	1291.00	AQEU
GENMAB A/S	15-Apr-2025	4:16:32 PM	20	1291.00	AQEU
GENMAB A/S	15-Apr-2025	4:16:43 PM	1	1291.50	XCSE
GENMAB A/S	15-Apr-2025	4:16:49 PM	15	1292.00	XCSE
GENMAB A/S	15-Apr-2025	4:16:49 PM	57	1292.00	XCSE
GENMAB A/S	15-Apr-2025	4:16:49 PM	18	1292.00	XCSE
GENMAB A/S	15-Apr-2025	4:16:49 PM	15	1292.00	XCSE
GENMAB A/S	15-Apr-2025	4:16:49 PM	9	1292.00	XCSE
GENMAB A/S	15-Apr-2025	4:17:15 PM	85	1291.00	XCSE
GENMAB A/S	15-Apr-2025	4:17:15 PM	4	1291.00	TQEX
GENMAB A/S	15-Apr-2025	4:17:15 PM	35	1291.00	TQEX
GENMAB A/S	15-Apr-2025	4:17:15 PM	67	1291.50	CEUX
GENMAB A/S	15-Apr-2025	4:17:15 PM	4	1290.50	CEUX
GENMAB A/S	15-Apr-2025	4:17:30 PM	84	1290.00	XCSE
GENMAB A/S	15-Apr-2025	4:17:30 PM	38	1291.00	CEUX
GENMAB A/S	15-Apr-2025	4:17:31 PM	84	1289.00	XCSE
GENMAB A/S	15-Apr-2025	4:17:31 PM	47	1289.50	CEUX
GENMAB A/S	15-Apr-2025	4:17:34 PM	91	1287.50	XCSE
GENMAB A/S	15-Apr-2025	4:17:34 PM	37	1288.00	CEUX
GENMAB A/S	15-Apr-2025	4:17:35 PM	85	1286.50	XCSE
GENMAB A/S	15-Apr-2025	4:17:42 PM	26	1287.00	XCSE
GENMAB A/S	15-Apr-2025	4:17:49 PM	38	1286.50	CEUX
GENMAB A/S	15-Apr-2025	4:17:49 PM	4	1286.50	CEUX
GENMAB A/S	15-Apr-2025	4:17:57 PM	26	1285.50	XCSE
GENMAB A/S	15-Apr-2025	4:17:57 PM	25	1285.50	CEUX
GENMAB A/S	15-Apr-2025	4:17:57 PM	25	1285.50	AQEU
GENMAB A/S	15-Apr-2025	4:18:00 PM	43	1285.00	CEUX
GENMAB A/S	15-Apr-2025	4:18:06 PM	28	1285.50	XCSE
GENMAB A/S	15-Apr-2025	4:18:43 PM	47	1286.50	XCSE
GENMAB A/S	15-Apr-2025	4:18:49 PM	39	1286.00	TQEX
GENMAB A/S	15-Apr-2025	4:18:57 PM	1	1286.00	AQEU
GENMAB A/S	15-Apr-2025	4:18:57 PM	24	1286.00	AQEU
GENMAB A/S	15-Apr-2025	4:19:03 PM	3	1285.50	XCSE
GENMAB A/S	15-Apr-2025	4:19:03 PM	27	1285.50	CEUX

128

Exhibit 99.1(a)

APPENDIX Share buy-back programme - Specification for April 14 – April 18, 2025

GENMAB A/S	15-Apr-2025	4:19:21 PM	31	1284.50	XCSE
GENMAB A/S	15-Apr-2025	4:19:21 PM	26	1284.50	CEUX
GENMAB A/S	15-Apr-2025	4:19:33 PM	15	1284.00	XCSE
GENMAB A/S	15-Apr-2025	4:19:33 PM	49	1284.00	XCSE
GENMAB A/S	15-Apr-2025	4:19:34 PM	29	1283.50	CEUX
GENMAB A/S	15-Apr-2025	4:19:51 PM	28	1284.00	XCSE
GENMAB A/S	15-Apr-2025	4:19:51 PM	5	1284.00	XCSE
GENMAB A/S	15-Apr-2025	4:19:51 PM	57	1284.00	XCSE
GENMAB A/S	15-Apr-2025	4:20:02 PM	17	1284.50	CEUX
GENMAB A/S	15-Apr-2025	4:20:02 PM	10	1284.50	CEUX
GENMAB A/S	15-Apr-2025	4:20:02 PM	6	1284.50	CEUX
GENMAB A/S	15-Apr-2025	4:20:02 PM	15	1284.50	CEUX
GENMAB A/S	15-Apr-2025	4:20:16 PM	90	1284.00	XCSE
GENMAB A/S	15-Apr-2025	4:20:16 PM	31	1284.50	XCSE
GENMAB A/S	15-Apr-2025	4:20:18 PM	41	1283.50	CEUX
GENMAB A/S	15-Apr-2025	4:20:18 PM	8	1283.50	CEUX
GENMAB A/S	15-Apr-2025	4:20:18 PM	3	1283.50	CEUX
GENMAB A/S	15-Apr-2025	4:20:18 PM	8	1283.50	CEUX
GENMAB A/S	15-Apr-2025	4:20:18 PM	3	1283.50	CEUX
GENMAB A/S	15-Apr-2025	4:20:18 PM	3	1283.50	CEUX
GENMAB A/S	15-Apr-2025	4:20:18 PM	3	1283.50	CEUX
GENMAB A/S	15-Apr-2025	4:20:18 PM	2	1283.50	CEUX
GENMAB A/S	15-Apr-2025	4:20:18 PM	2	1283.50	CEUX
GENMAB A/S	15-Apr-2025	4:20:18 PM	7	1283.50	CEUX
GENMAB A/S	15-Apr-2025	4:20:18 PM	3	1283.50	CEUX
GENMAB A/S	15-Apr-2025	4:20:18 PM	45	1284.00	AQEU
GENMAB A/S	15-Apr-2025	4:20:34 PM	24	1284.00	XCSE
GENMAB A/S	15-Apr-2025	4:20:34 PM	15	1284.00	XCSE
GENMAB A/S	15-Apr-2025	4:20:34 PM	52	1284.00	XCSE
GENMAB A/S	15-Apr-2025	4:20:34 PM	26	1284.00	CEUX
GENMAB A/S	15-Apr-2025	4:20:51 PM	36	1284.50	CEUX
GENMAB A/S	15-Apr-2025	4:21:10 PM	30	1285.50	CEUX
GENMAB A/S	15-Apr-2025	4:21:13 PM	48	1286.00	XCSE
GENMAB A/S	15-Apr-2025	4:21:13 PM	35	1286.00	XCSE
GENMAB A/S	15-Apr-2025	4:21:13 PM	17	1286.00	XCSE
GENMAB A/S	15-Apr-2025	4:21:25 PM	19	1285.50	CEUX
GENMAB A/S	15-Apr-2025	4:21:25 PM	6	1285.50	CEUX
GENMAB A/S	15-Apr-2025	4:21:54 PM	88	1286.00	XCSE
GENMAB A/S	15-Apr-2025	4:21:54 PM	10	1286.00	TQEX
GENMAB A/S	15-Apr-2025	4:21:54 PM	20	1286.00	TQEX
GENMAB A/S	15-Apr-2025	4:21:54 PM	13	1286.00	TQEX
GENMAB A/S	15-Apr-2025	4:21:54 PM	5	1286.00	AQEU
GENMAB A/S	15-Apr-2025	4:21:54 PM	20	1286.00	AQEU

129

Exhibit 99.1(a)

APPENDIX Share buy-back programme - Specification for April 14 – April 18, 2025

GENMAB A/S	15-Apr-2025	4:21:54 PM	6	1286.00	AQEU
GENMAB A/S	15-Apr-2025	4:21:54 PM	5	1286.00	AQEU
GENMAB A/S	15-Apr-2025	4:21:54 PM	2	1286.00	AQEU
GENMAB A/S	15-Apr-2025	4:22:03 PM	3	1286.50	CEUX
GENMAB A/S	15-Apr-2025	4:22:03 PM	6	1286.50	CEUX
GENMAB A/S	15-Apr-2025	4:22:03 PM	20	1286.50	CEUX
GENMAB A/S	15-Apr-2025	4:22:03 PM	5	1286.50	CEUX
GENMAB A/S	15-Apr-2025	4:22:03 PM	17	1286.50	CEUX
GENMAB A/S	15-Apr-2025	4:22:03 PM	5	1286.50	CEUX
GENMAB A/S	15-Apr-2025	4:22:13 PM	3	1287.50	XCSE
GENMAB A/S	15-Apr-2025	4:22:23 PM	2	1287.50	XCSE
GENMAB A/S	15-Apr-2025	4:22:38 PM	62	1287.00	XCSE
GENMAB A/S	15-Apr-2025	4:22:38 PM	29	1287.00	XCSE
GENMAB A/S	15-Apr-2025	4:22:39 PM	20	1286.00	XCSE
GENMAB A/S	15-Apr-2025	4:22:48 PM	1	1286.50	CEUX
GENMAB A/S	15-Apr-2025	4:22:53 PM	5	1286.50	XCSE
GENMAB A/S	15-Apr-2025	4:22:53 PM	24	1286.50	XCSE
GENMAB A/S	15-Apr-2025	4:22:54 PM	114	1287.00	XCSE
GENMAB A/S	15-Apr-2025	4:23:14 PM	34	1287.00	XCSE
GENMAB A/S	15-Apr-2025	4:23:14 PM	13	1287.00	XCSE
GENMAB A/S	15-Apr-2025	4:23:14 PM	57	1287.00	XCSE
GENMAB A/S	15-Apr-2025	4:23:49 PM	62	1287.50	XCSE
GENMAB A/S	15-Apr-2025	4:23:49 PM	89	1287.00	XCSE
GENMAB A/S	15-Apr-2025	4:24:02 PM	4	1287.00	XCSE
GENMAB A/S	15-Apr-2025	4:24:02 PM	8	1287.00	XCSE
GENMAB A/S	15-Apr-2025	4:24:02 PM	2	1287.00	XCSE
GENMAB A/S	15-Apr-2025	4:24:02 PM	11	1287.00	XCSE
GENMAB A/S	15-Apr-2025	4:24:02 PM	3	1286.50	TQEX
GENMAB A/S	15-Apr-2025	4:24:02 PM	22	1286.50	TQEX
GENMAB A/S	15-Apr-2025	4:24:02 PM	2	1286.50	CEUX
GENMAB A/S	15-Apr-2025	4:24:02 PM	68	1286.50	CEUX
GENMAB A/S	15-Apr-2025	4:24:02 PM	16	1287.00	AQEU
GENMAB A/S	15-Apr-2025	4:24:02 PM	20	1287.00	AQEU
GENMAB A/S	15-Apr-2025	4:24:41 PM	21	1286.00	XCSE
GENMAB A/S	15-Apr-2025	4:24:41 PM	91	1286.50	CEUX
GENMAB A/S	15-Apr-2025	4:24:41 PM	32	1287.00	CEUX
GENMAB A/S	15-Apr-2025	4:25:32 PM	57	1288.00	XCSE
GENMAB A/S	15-Apr-2025	4:25:32 PM	29	1288.00	XCSE
GENMAB A/S	15-Apr-2025	4:25:32 PM	18	1288.00	XCSE
GENMAB A/S	15-Apr-2025	4:25:32 PM	10	1288.00	XCSE
GENMAB A/S	15-Apr-2025	4:25:32 PM	59	1287.00	XCSE
GENMAB A/S	15-Apr-2025	4:25:32 PM	11	1288.00	CEUX
GENMAB A/S	15-Apr-2025	4:25:38 PM	45	1289.00	XCSE

130

Exhibit 99.1(a)

APPENDIX Share buy-back programme - Specification for April 14 – April 18, 2025

GENMAB A/S	15-Apr-2025	4:25:40 PM	5	1289.00	XCSE
GENMAB A/S	15-Apr-2025	4:25:57 PM	30	1289.00	XCSE
GENMAB A/S	15-Apr-2025	4:25:57 PM	57	1289.00	XCSE
GENMAB A/S	15-Apr-2025	4:25:57 PM	18	1289.00	XCSE
GENMAB A/S	15-Apr-2025	4:25:57 PM	9	1289.00	XCSE
GENMAB A/S	15-Apr-2025	4:25:57 PM	2	1288.50	TQEX
GENMAB A/S	15-Apr-2025	4:25:57 PM	16	1288.50	TQEX
GENMAB A/S	15-Apr-2025	4:25:57 PM	2	1288.50	TQEX
GENMAB A/S	15-Apr-2025	4:25:57 PM	20	1288.50	CEUX
GENMAB A/S	15-Apr-2025	4:25:57 PM	36	1289.00	CEUX
GENMAB A/S	15-Apr-2025	4:25:57 PM	7	1289.00	CEUX
GENMAB A/S	15-Apr-2025	4:25:57 PM	64	1288.50	CEUX
GENMAB A/S	15-Apr-2025	4:25:58 PM	47	1289.00	XCSE
GENMAB A/S	15-Apr-2025	4:25:58 PM	15	1289.00	XCSE
GENMAB A/S	15-Apr-2025	4:25:58 PM	52	1289.00	XCSE
GENMAB A/S	15-Apr-2025	4:26:03 PM	10	1288.50	TQEX
GENMAB A/S	15-Apr-2025	4:26:08 PM	37	1288.50	XCSE
GENMAB A/S	15-Apr-2025	4:26:08 PM	64	1288.00	XCSE
GENMAB A/S	15-Apr-2025	4:26:08 PM	24	1288.00	XCSE
GENMAB A/S	15-Apr-2025	4:26:08 PM	3	1288.50	TQEX
GENMAB A/S	15-Apr-2025	4:26:17 PM	28	1287.50	TQEX
GENMAB A/S	15-Apr-2025	4:26:17 PM	59	1287.50	CEUX
GENMAB A/S	15-Apr-2025	4:26:17 PM	27	1287.50	CEUX
GENMAB A/S	15-Apr-2025	4:26:17 PM	39	1287.50	AQEU
GENMAB A/S	15-Apr-2025	4:27:06 PM	114	1288.50	XCSE
GENMAB A/S	15-Apr-2025	4:27:06 PM	59	1288.00	XCSE
GENMAB A/S	15-Apr-2025	4:27:09 PM	30	1288.00	XCSE
GENMAB A/S	15-Apr-2025	4:27:09 PM	2	1288.00	XCSE
GENMAB A/S	15-Apr-2025	4:27:09 PM	32	1288.50	CEUX
GENMAB A/S	15-Apr-2025	4:27:09 PM	5	1287.50	CEUX
GENMAB A/S	15-Apr-2025	4:27:28 PM	38	1287.50	CEUX
GENMAB A/S	15-Apr-2025	4:27:29 PM	26	1287.00	XCSE
GENMAB A/S	15-Apr-2025	4:27:41 PM	3	1287.00	XCSE
GENMAB A/S	15-Apr-2025	4:27:58 PM	90	1289.00	CEUX
GENMAB A/S	15-Apr-2025	4:28:00 PM	36	1289.00	AQEU
GENMAB A/S	15-Apr-2025	4:28:19 PM	81	1289.00	CEUX
GENMAB A/S	15-Apr-2025	4:28:52 PM	86	1289.50	XCSE
GENMAB A/S	15-Apr-2025	4:28:52 PM	10	1289.50	XCSE
GENMAB A/S	15-Apr-2025	4:28:52 PM	10	1289.50	XCSE
GENMAB A/S	15-Apr-2025	4:28:52 PM	15	1289.50	XCSE
GENMAB A/S	15-Apr-2025	4:28:52 PM	13	1289.50	XCSE
GENMAB A/S	15-Apr-2025	4:28:52 PM	17	1289.50	XCSE
GENMAB A/S	15-Apr-2025	4:28:52 PM	15	1289.50	XCSE

131

Exhibit 99.1(a)

APPENDIX Share buy-back programme - Specification for April 14 – April 18, 2025

GENMAB A/S	15-Apr-2025	4:28:52 PM	10	1289.50	TQEX
GENMAB A/S	15-Apr-2025	4:28:52 PM	34	1289.50	TQEX
GENMAB A/S	15-Apr-2025	4:28:52 PM	1	1289.00	CEUX
GENMAB A/S	15-Apr-2025	4:28:58 PM	89	1288.50	XCSE
GENMAB A/S	15-Apr-2025	4:28:58 PM	18	1288.50	XCSE
GENMAB A/S	15-Apr-2025	4:28:58 PM	18	1288.50	XCSE
GENMAB A/S	15-Apr-2025	4:28:58 PM	4	1288.50	XCSE
GENMAB A/S	15-Apr-2025	4:28:58 PM	2	1288.50	XCSE
GENMAB A/S	15-Apr-2025	4:28:58 PM	5	1288.50	XCSE
GENMAB A/S	15-Apr-2025	4:28:58 PM	3	1288.50	XCSE
GENMAB A/S	15-Apr-2025	4:28:58 PM	3	1288.50	XCSE
GENMAB A/S	15-Apr-2025	4:28:58 PM	3	1288.50	XCSE
GENMAB A/S	15-Apr-2025	4:28:58 PM	10	1288.50	XCSE
GENMAB A/S	15-Apr-2025	4:28:58 PM	35	1289.00	XCSE
GENMAB A/S	15-Apr-2025	4:28:58 PM	13	1289.00	XCSE
GENMAB A/S	15-Apr-2025	4:29:21 PM	45	1287.50	XCSE
GENMAB A/S	15-Apr-2025	4:29:21 PM	36	1288.50	CEUX
GENMAB A/S	15-Apr-2025	4:29:21 PM	7	1288.50	CEUX
GENMAB A/S	15-Apr-2025	4:29:21 PM	6	1288.50	CEUX
GENMAB A/S	15-Apr-2025	4:29:37 PM	46	1287.50	XCSE
GENMAB A/S	15-Apr-2025	4:29:37 PM	15	1288.00	XCSE
GENMAB A/S	15-Apr-2025	4:29:37 PM	18	1288.00	XCSE
GENMAB A/S	15-Apr-2025	4:29:37 PM	57	1288.00	XCSE
GENMAB A/S	15-Apr-2025	4:29:37 PM	17	1288.00	XCSE
GENMAB A/S	15-Apr-2025	4:29:37 PM	7	1288.00	XCSE
GENMAB A/S	15-Apr-2025	4:29:37 PM	4	1288.00	CEUX
GENMAB A/S	15-Apr-2025	4:29:37 PM	8	1288.00	CEUX
GENMAB A/S	15-Apr-2025	4:29:37 PM	7	1288.00	CEUX
GENMAB A/S	15-Apr-2025	4:29:37 PM	5	1288.00	CEUX
GENMAB A/S	15-Apr-2025	4:29:37 PM	3	1287.50	CEUX
GENMAB A/S	15-Apr-2025	4:29:37 PM	23	1287.50	CEUX
GENMAB A/S	15-Apr-2025	4:29:37 PM	58	1287.50	CEUX
GENMAB A/S	15-Apr-2025	4:30:02 PM	45	1287.50	XCSE
GENMAB A/S	15-Apr-2025	4:30:02 PM	31	1287.00	XCSE
GENMAB A/S	15-Apr-2025	4:30:03 PM	55	1287.00	XCSE
GENMAB A/S	15-Apr-2025	4:30:15 PM	8	1287.50	CEUX
GENMAB A/S	15-Apr-2025	4:30:24 PM	14	1287.00	AQEU
GENMAB A/S	15-Apr-2025	4:30:28 PM	47	1287.00	XCSE
GENMAB A/S	15-Apr-2025	4:30:28 PM	7	1287.00	CEUX
GENMAB A/S	15-Apr-2025	4:30:29 PM	8	1287.00	CEUX
GENMAB A/S	15-Apr-2025	4:30:33 PM	82	1287.00	XCSE
GENMAB A/S	15-Apr-2025	4:30:33 PM	5	1286.50	TQEX
GENMAB A/S	15-Apr-2025	4:30:33 PM	70	1286.50	CEUX

132

Exhibit 99.1(a)

APPENDIX Share buy-back programme - Specification for April 14 – April 18, 2025

GENMAB A/S	15-Apr-2025	4:30:33 PM	21	1287.00	AQEU
GENMAB A/S	15-Apr-2025	4:31:00 PM	32	1287.50	CEUX
GENMAB A/S	15-Apr-2025	4:31:12 PM	57	1287.50	XCSE
GENMAB A/S	15-Apr-2025	4:31:12 PM	15	1287.50	XCSE
GENMAB A/S	15-Apr-2025	4:31:12 PM	15	1287.50	XCSE
GENMAB A/S	15-Apr-2025	4:31:12 PM	18	1287.50	XCSE
GENMAB A/S	15-Apr-2025	4:31:12 PM	9	1287.50	XCSE
GENMAB A/S	15-Apr-2025	4:31:12 PM	15	1287.00	CEUX
GENMAB A/S	15-Apr-2025	4:31:12 PM	10	1287.00	CEUX
GENMAB A/S	15-Apr-2025	4:31:12 PM	15	1287.00	CEUX
GENMAB A/S	15-Apr-2025	4:31:12 PM	38	1287.00	CEUX
GENMAB A/S	15-Apr-2025	4:31:21 PM	13	1287.00	CEUX
GENMAB A/S	15-Apr-2025	4:31:51 PM	91	1287.00	XCSE
GENMAB A/S	15-Apr-2025	4:31:51 PM	2	1286.50	TQEX
GENMAB A/S	15-Apr-2025	4:31:51 PM	43	1287.00	CEUX
GENMAB A/S	15-Apr-2025	4:32:02 PM	13	1287.50	TQEX
GENMAB A/S	15-Apr-2025	4:32:02 PM	20	1287.50	TQEX
GENMAB A/S	15-Apr-2025	4:32:02 PM	2	1287.50	TQEX
GENMAB A/S	15-Apr-2025	4:32:11 PM	32	1287.50	CEUX
GENMAB A/S	15-Apr-2025	4:32:12 PM	35	1288.00	XCSE
GENMAB A/S	15-Apr-2025	4:32:18 PM	35	1288.50	XCSE
GENMAB A/S	15-Apr-2025	4:32:18 PM	90	1288.00	XCSE
GENMAB A/S	15-Apr-2025	4:32:36 PM	3	1288.00	XCSE
GENMAB A/S	15-Apr-2025	4:32:36 PM	4	1287.50	TQEX
GENMAB A/S	15-Apr-2025	4:32:36 PM	36	1288.50	CEUX
GENMAB A/S	15-Apr-2025	4:32:36 PM	8	1288.50	CEUX
GENMAB A/S	15-Apr-2025	4:32:36 PM	14	1288.00	AQEU
GENMAB A/S	15-Apr-2025	4:32:36 PM	11	1288.00	AQEU
GENMAB A/S	15-Apr-2025	4:32:38 PM	48	1288.00	XCSE
GENMAB A/S	15-Apr-2025	4:32:38 PM	17	1288.00	XCSE
GENMAB A/S	15-Apr-2025	4:32:38 PM	14	1288.00	XCSE
GENMAB A/S	15-Apr-2025	4:32:38 PM	17	1288.00	XCSE
GENMAB A/S	15-Apr-2025	4:32:38 PM	18	1288.00	XCSE
GENMAB A/S	15-Apr-2025	4:32:43 PM	48	1288.00	XCSE
GENMAB A/S	15-Apr-2025	4:32:43 PM	1	1288.00	XCSE
GENMAB A/S	15-Apr-2025	4:32:43 PM	36	1288.00	CEUX
GENMAB A/S	15-Apr-2025	4:32:43 PM	2	1288.00	CEUX
GENMAB A/S	15-Apr-2025	4:33:28 PM	87	1288.00	CEUX
GENMAB A/S	15-Apr-2025	4:34:08 PM	4	1287.50	XCSE
GENMAB A/S	15-Apr-2025	4:34:08 PM	5	1287.50	XCSE
GENMAB A/S	15-Apr-2025	4:34:08 PM	5	1287.50	XCSE
GENMAB A/S	15-Apr-2025	4:34:08 PM	6	1287.50	XCSE
GENMAB A/S	15-Apr-2025	4:34:08 PM	3	1287.50	XCSE

133

Exhibit 99.1(a)

APPENDIX Share buy-back programme - Specification for April 14 – April 18, 2025

GENMAB A/S	15-Apr-2025	4:34:08 PM	2	1287.50	XCSE
GENMAB A/S	15-Apr-2025	4:34:08 PM	15	1287.50	XCSE
GENMAB A/S	15-Apr-2025	4:34:08 PM	3	1287.50	XCSE
GENMAB A/S	15-Apr-2025	4:34:08 PM	16	1287.50	XCSE
GENMAB A/S	15-Apr-2025	4:34:08 PM	22	1287.50	TQEX
GENMAB A/S	15-Apr-2025	4:34:08 PM	4	1287.00	CEUX
GENMAB A/S	15-Apr-2025	4:34:08 PM	36	1288.00	CEUX
GENMAB A/S	15-Apr-2025	4:34:08 PM	8	1288.00	CEUX
GENMAB A/S	15-Apr-2025	4:34:08 PM	8	1288.00	CEUX
GENMAB A/S	15-Apr-2025	4:34:08 PM	26	1288.00	CEUX
GENMAB A/S	15-Apr-2025	4:34:08 PM	1	1287.00	CEUX
GENMAB A/S	15-Apr-2025	4:34:08 PM	32	1287.00	CEUX
GENMAB A/S	15-Apr-2025	4:34:08 PM	10	1287.00	CEUX
GENMAB A/S	15-Apr-2025	4:34:08 PM	22	1287.00	CEUX
GENMAB A/S	15-Apr-2025	4:34:08 PM	25	1288.00	AQEU
GENMAB A/S	15-Apr-2025	4:34:20 PM	50	1288.00	XCSE
GENMAB A/S	15-Apr-2025	4:34:20 PM	10	1288.00	XCSE
GENMAB A/S	15-Apr-2025	4:34:20 PM	5	1288.00	XCSE
GENMAB A/S	15-Apr-2025	4:34:20 PM	10	1288.00	XCSE
GENMAB A/S	15-Apr-2025	4:34:20 PM	5	1288.00	XCSE
GENMAB A/S	15-Apr-2025	4:34:20 PM	5	1288.00	XCSE
GENMAB A/S	15-Apr-2025	4:34:20 PM	5	1288.00	XCSE
GENMAB A/S	15-Apr-2025	4:34:20 PM	15	1288.00	AQEU
GENMAB A/S	15-Apr-2025	4:34:20 PM	10	1288.00	AQEU
GENMAB A/S	15-Apr-2025	4:34:21 PM	15	1288.00	XCSE
GENMAB A/S	15-Apr-2025	4:34:21 PM	15	1288.00	XCSE
GENMAB A/S	15-Apr-2025	4:34:21 PM	57	1288.00	XCSE
GENMAB A/S	15-Apr-2025	4:34:21 PM	27	1288.00	XCSE
GENMAB A/S	15-Apr-2025	4:34:21 PM	18	1288.00	XCSE
GENMAB A/S	15-Apr-2025	4:34:21 PM	24	1288.00	XCSE
GENMAB A/S	15-Apr-2025	4:34:21 PM	15	1288.00	XCSE
GENMAB A/S	15-Apr-2025	4:34:21 PM	15	1287.50	TQEX
GENMAB A/S	15-Apr-2025	4:34:47 PM	16	1288.00	XCSE
GENMAB A/S	15-Apr-2025	4:34:47 PM	26	1288.00	XCSE
GENMAB A/S	15-Apr-2025	4:34:47 PM	18	1288.00	XCSE
GENMAB A/S	15-Apr-2025	4:34:47 PM	34	1288.00	XCSE
GENMAB A/S	15-Apr-2025	4:34:47 PM	20	1288.00	XCSE
GENMAB A/S	15-Apr-2025	4:34:47 PM	32	1288.00	CEUX
GENMAB A/S	15-Apr-2025	4:34:47 PM	59	1287.50	CEUX
GENMAB A/S	15-Apr-2025	4:34:48 PM	47	1288.00	XCSE
GENMAB A/S	15-Apr-2025	4:34:48 PM	16	1288.00	XCSE
GENMAB A/S	15-Apr-2025	4:34:48 PM	17	1288.00	XCSE
GENMAB A/S	15-Apr-2025	4:34:48 PM	15	1288.00	XCSE

134

Exhibit 99.1(a)

APPENDIX Share buy-back programme - Specification for April 14 – April 18, 2025

GENMAB A/S	15-Apr-2025	4:34:48 PM	14	1288.00	XCSE
GENMAB A/S	15-Apr-2025	4:34:48 PM	32	1287.50	TQEX
GENMAB A/S	15-Apr-2025	4:34:49 PM	3	1287.00	XCSE
GENMAB A/S	15-Apr-2025	4:34:49 PM	5	1287.00	XCSE
GENMAB A/S	15-Apr-2025	4:34:49 PM	11	1287.50	CEUX
GENMAB A/S	15-Apr-2025	4:34:49 PM	14	1287.50	CEUX
GENMAB A/S	15-Apr-2025	4:34:49 PM	3	1287.50	CEUX
GENMAB A/S	15-Apr-2025	4:34:49 PM	4	1287.50	CEUX
GENMAB A/S	15-Apr-2025	4:34:49 PM	4	1287.50	CEUX
GENMAB A/S	15-Apr-2025	4:34:49 PM	6	1287.50	CEUX
GENMAB A/S	15-Apr-2025	4:34:49 PM	15	1287.50	CEUX
GENMAB A/S	15-Apr-2025	4:34:49 PM	5	1287.50	CEUX
GENMAB A/S	15-Apr-2025	4:34:49 PM	5	1287.50	CEUX
GENMAB A/S	15-Apr-2025	4:34:55 PM	32	1288.00	XCSE
GENMAB A/S	15-Apr-2025	4:34:55 PM	3	1288.00	CEUX
GENMAB A/S	15-Apr-2025	4:34:55 PM	20	1288.00	CEUX
GENMAB A/S	15-Apr-2025	4:34:55 PM	6	1288.00	CEUX
GENMAB A/S	15-Apr-2025	4:35:03 PM	34	1288.50	XCSE
GENMAB A/S	15-Apr-2025	4:35:03 PM	34	1288.50	CEUX
GENMAB A/S	15-Apr-2025	4:35:11 PM	79	1287.00	XCSE
GENMAB A/S	15-Apr-2025	4:35:11 PM	2	1287.00	XCSE
GENMAB A/S	15-Apr-2025	4:35:11 PM	31	1287.00	CEUX
GENMAB A/S	15-Apr-2025	4:35:40 PM	31	1286.50	XCSE
GENMAB A/S	15-Apr-2025	4:35:41 PM	26	1286.50	XCSE
GENMAB A/S	15-Apr-2025	4:35:41 PM	14	1286.50	XCSE
GENMAB A/S	15-Apr-2025	4:36:03 PM	4	1287.00	XCSE
GENMAB A/S	15-Apr-2025	4:36:03 PM	57	1287.00	XCSE
GENMAB A/S	15-Apr-2025	4:36:03 PM	2	1287.50	XCSE
GENMAB A/S	15-Apr-2025	4:36:03 PM	4	1287.00	CEUX
GENMAB A/S	15-Apr-2025	4:36:03 PM	3	1287.00	CEUX
GENMAB A/S	15-Apr-2025	4:36:03 PM	22	1287.00	CEUX
GENMAB A/S	15-Apr-2025	4:36:03 PM	25	1287.00	CEUX
GENMAB A/S	15-Apr-2025	4:36:03 PM	8	1287.00	CEUX
GENMAB A/S	15-Apr-2025	4:36:14 PM	74	1288.00	XCSE
GENMAB A/S	15-Apr-2025	4:36:14 PM	4	1288.00	TQEX
GENMAB A/S	15-Apr-2025	4:36:14 PM	21	1288.00	TQEX
GENMAB A/S	15-Apr-2025	4:36:14 PM	7	1288.00	CEUX
GENMAB A/S	15-Apr-2025	4:36:14 PM	27	1288.00	CEUX
GENMAB A/S	15-Apr-2025	4:36:14 PM	2	1288.00	AQEU
GENMAB A/S	15-Apr-2025	4:36:14 PM	3	1288.00	AQEU
GENMAB A/S	15-Apr-2025	4:36:15 PM	9	1288.00	XCSE
GENMAB A/S	15-Apr-2025	4:36:15 PM	9	1288.00	XCSE
GENMAB A/S	15-Apr-2025	4:36:15 PM	7	1288.00	XCSE

135

Exhibit 99.1(a)

APPENDIX Share buy-back programme - Specification for April 14 – April 18, 2025

GENMAB A/S	15-Apr-2025	4:36:15 PM	21	1288.00	AQEU
GENMAB A/S	15-Apr-2025	4:36:17 PM	65	1287.00	XCSE
GENMAB A/S	15-Apr-2025	4:36:17 PM	7	1287.00	CEUX
GENMAB A/S	15-Apr-2025	4:36:17 PM	10	1287.00	CEUX
GENMAB A/S	15-Apr-2025	4:36:17 PM	12	1287.00	CEUX
GENMAB A/S	15-Apr-2025	4:36:17 PM	3	1287.00	CEUX
GENMAB A/S	15-Apr-2025	4:36:17 PM	7	1287.00	CEUX
GENMAB A/S	15-Apr-2025	4:36:17 PM	12	1287.00	CEUX
GENMAB A/S	15-Apr-2025	4:36:36 PM	39	1288.50	CEUX
GENMAB A/S	15-Apr-2025	4:36:37 PM	37	1288.00	XCSE
GENMAB A/S	15-Apr-2025	4:36:43 PM	45	1288.50	XCSE
GENMAB A/S	15-Apr-2025	4:36:49 PM	47	1288.00	XCSE
GENMAB A/S	15-Apr-2025	4:36:49 PM	28	1288.50	AQEU
GENMAB A/S	15-Apr-2025	4:36:50 PM	18	1287.50	TQEX
GENMAB A/S	15-Apr-2025	4:36:50 PM	28	1287.50	CEUX
GENMAB A/S	15-Apr-2025	4:37:11 PM	24	1287.00	XCSE
GENMAB A/S	15-Apr-2025	4:37:11 PM	28	1287.50	CEUX
GENMAB A/S	15-Apr-2025	4:37:11 PM	7	1287.50	CEUX
GENMAB A/S	15-Apr-2025	4:37:21 PM	74	1287.50	XCSE
GENMAB A/S	15-Apr-2025	4:37:21 PM	9	1287.50	XCSE
GENMAB A/S	15-Apr-2025	4:37:25 PM	3	1287.50	XCSE
GENMAB A/S	15-Apr-2025	4:37:25 PM	2	1286.50	XCSE
GENMAB A/S	15-Apr-2025	4:37:25 PM	11	1286.50	XCSE
GENMAB A/S	15-Apr-2025	4:37:25 PM	12	1286.50	XCSE
GENMAB A/S	15-Apr-2025	4:37:35 PM	45	1286.50	XCSE
GENMAB A/S	15-Apr-2025	4:37:35 PM	10	1286.00	XCSE
GENMAB A/S	15-Apr-2025	4:37:35 PM	26	1286.00	CEUX
GENMAB A/S	15-Apr-2025	4:37:39 PM	78	1286.00	XCSE
GENMAB A/S	15-Apr-2025	4:38:10 PM	12	1286.50	XCSE
GENMAB A/S	15-Apr-2025	4:38:10 PM	2	1286.50	XCSE
GENMAB A/S	15-Apr-2025	4:38:10 PM	3	1286.50	XCSE
GENMAB A/S	15-Apr-2025	4:38:10 PM	3	1286.50	XCSE
GENMAB A/S	15-Apr-2025	4:38:10 PM	8	1286.50	XCSE
GENMAB A/S	15-Apr-2025	4:38:10 PM	3	1286.50	XCSE
GENMAB A/S	15-Apr-2025	4:38:10 PM	14	1286.50	XCSE
GENMAB A/S	15-Apr-2025	4:38:10 PM	25	1286.50	XCSE
GENMAB A/S	15-Apr-2025	4:38:10 PM	9	1286.50	XCSE
GENMAB A/S	15-Apr-2025	4:38:10 PM	8	1286.50	XCSE
GENMAB A/S	15-Apr-2025	4:38:10 PM	4	1286.00	TQEX
GENMAB A/S	15-Apr-2025	4:38:10 PM	9	1286.00	TQEX
GENMAB A/S	15-Apr-2025	4:38:10 PM	4	1286.00	TQEX
GENMAB A/S	15-Apr-2025	4:38:10 PM	4	1286.00	TQEX
GENMAB A/S	15-Apr-2025	4:38:10 PM	7	1286.00	TQEX

136

Exhibit 99.1(a)

APPENDIX Share buy-back programme - Specification for April 14 – April 18, 2025

GENMAB A/S	15-Apr-2025	4:38:31 PM	15	1287.00	CEUX
GENMAB A/S	15-Apr-2025	4:38:31 PM	36	1287.00	CEUX
GENMAB A/S	15-Apr-2025	4:38:31 PM	8	1287.00	CEUX
GENMAB A/S	15-Apr-2025	4:38:31 PM	8	1287.00	CEUX
GENMAB A/S	15-Apr-2025	4:39:01 PM	1	1286.00	TQEX
GENMAB A/S	15-Apr-2025	4:39:01 PM	69	1286.00	CEUX
GENMAB A/S	15-Apr-2025	4:39:01 PM	36	1286.50	CEUX
GENMAB A/S	15-Apr-2025	4:39:01 PM	3	1286.50	CEUX
GENMAB A/S	15-Apr-2025	4:39:01 PM	32	1286.50	AQEU
GENMAB A/S	15-Apr-2025	4:39:34 PM	8	1287.00	XCSE
GENMAB A/S	15-Apr-2025	4:39:34 PM	35	1287.00	XCSE
GENMAB A/S	15-Apr-2025	4:39:34 PM	16	1287.00	XCSE
GENMAB A/S	15-Apr-2025	4:39:34 PM	15	1287.00	XCSE
GENMAB A/S	15-Apr-2025	4:39:34 PM	48	1287.00	XCSE
GENMAB A/S	15-Apr-2025	4:39:34 PM	15	1286.50	TQEX
GENMAB A/S	15-Apr-2025	4:39:34 PM	8	1287.00	CEUX
GENMAB A/S	15-Apr-2025	4:39:34 PM	8	1287.00	CEUX
GENMAB A/S	15-Apr-2025	4:39:35 PM	15	1287.00	XCSE
GENMAB A/S	15-Apr-2025	4:39:35 PM	19	1287.00	XCSE
GENMAB A/S	15-Apr-2025	4:39:35 PM	17	1287.00	XCSE
GENMAB A/S	15-Apr-2025	4:39:36 PM	17	1287.00	XCSE
GENMAB A/S	15-Apr-2025	4:39:36 PM	16	1287.00	XCSE
GENMAB A/S	15-Apr-2025	4:39:36 PM	7	1287.00	CEUX
GENMAB A/S	15-Apr-2025	4:39:36 PM	7	1287.00	CEUX
GENMAB A/S	15-Apr-2025	4:39:41 PM	15	1287.00	XCSE
GENMAB A/S	15-Apr-2025	4:39:41 PM	21	1287.00	XCSE
GENMAB A/S	15-Apr-2025	4:39:41 PM	57	1287.00	XCSE
GENMAB A/S	15-Apr-2025	4:39:41 PM	15	1287.00	XCSE
GENMAB A/S	15-Apr-2025	4:39:59 PM	4	1287.50	XCSE
GENMAB A/S	15-Apr-2025	4:39:59 PM	2	1287.50	XCSE
GENMAB A/S	15-Apr-2025	4:39:59 PM	5	1287.50	XCSE
GENMAB A/S	15-Apr-2025	4:39:59 PM	62	1287.50	XCSE
GENMAB A/S	15-Apr-2025	4:39:59 PM	2	1287.50	CEUX
GENMAB A/S	15-Apr-2025	4:40:03 PM	29	1287.50	XCSE
GENMAB A/S	15-Apr-2025	4:40:03 PM	19	1287.50	TQEX
GENMAB A/S	15-Apr-2025	4:40:03 PM	7	1287.50	TQEX
GENMAB A/S	15-Apr-2025	4:40:03 PM	3	1287.50	CEUX
GENMAB A/S	15-Apr-2025	4:40:03 PM	76	1287.50	CEUX
GENMAB A/S	15-Apr-2025	4:40:03 PM	5	1287.50	CEUX
GENMAB A/S	15-Apr-2025	4:40:03 PM	20	1287.50	CEUX
GENMAB A/S	15-Apr-2025	4:40:03 PM	4	1287.50	CEUX
GENMAB A/S	15-Apr-2025	4:40:03 PM	18	1287.50	AQEU
GENMAB A/S	15-Apr-2025	4:40:03 PM	3	1287.50	AQEU

137

Exhibit 99.1(a)

APPENDIX Share buy-back programme - Specification for April 14 – April 18, 2025

GENMAB A/S	15-Apr-2025	4:40:03 PM	3	1287.50	AQEU
GENMAB A/S	15-Apr-2025	4:40:03 PM	2	1287.50	AQEU
GENMAB A/S	15-Apr-2025	4:40:12 PM	15	1287.50	XCSE
GENMAB A/S	15-Apr-2025	4:40:12 PM	21	1287.50	XCSE
GENMAB A/S	15-Apr-2025	4:40:12 PM	57	1287.50	XCSE
GENMAB A/S	15-Apr-2025	4:40:12 PM	15	1287.50	XCSE
GENMAB A/S	15-Apr-2025	4:40:27 PM	15	1287.00	XCSE
GENMAB A/S	15-Apr-2025	4:40:27 PM	15	1287.00	XCSE
GENMAB A/S	15-Apr-2025	4:40:27 PM	25	1287.00	XCSE
GENMAB A/S	15-Apr-2025	4:40:27 PM	57	1287.00	XCSE
GENMAB A/S	15-Apr-2025	4:40:27 PM	2	1287.00	XCSE
GENMAB A/S	15-Apr-2025	4:40:27 PM	78	1286.50	XCSE
GENMAB A/S	15-Apr-2025	4:40:27 PM	11	1286.50	XCSE
GENMAB A/S	15-Apr-2025	4:40:27 PM	10	1286.50	TQEX
GENMAB A/S	15-Apr-2025	4:40:27 PM	36	1287.00	CEUX
GENMAB A/S	15-Apr-2025	4:40:27 PM	5	1286.50	CEUX
GENMAB A/S	15-Apr-2025	4:40:27 PM	15	1286.50	CEUX
GENMAB A/S	15-Apr-2025	4:40:27 PM	3	1286.50	CEUX
GENMAB A/S	15-Apr-2025	4:40:27 PM	10	1286.50	CEUX
GENMAB A/S	15-Apr-2025	4:40:27 PM	2	1286.50	CEUX
GENMAB A/S	15-Apr-2025	4:40:27 PM	45	1286.50	CEUX
GENMAB A/S	15-Apr-2025	4:41:02 PM	85	1287.00	XCSE
GENMAB A/S	15-Apr-2025	4:41:15 PM	36	1287.00	CEUX
GENMAB A/S	15-Apr-2025	4:41:15 PM	8	1287.00	CEUX
GENMAB A/S	15-Apr-2025	4:41:15 PM	21	1287.00	CEUX
GENMAB A/S	15-Apr-2025	4:41:31 PM	35	1287.00	XCSE
GENMAB A/S	15-Apr-2025	4:41:43 PM	7	1287.00	CEUX
GENMAB A/S	15-Apr-2025	4:41:43 PM	6	1287.00	CEUX
GENMAB A/S	15-Apr-2025	4:41:43 PM	11	1287.00	CEUX
GENMAB A/S	15-Apr-2025	4:41:43 PM	40	1287.00	AQEU
GENMAB A/S	15-Apr-2025	4:42:01 PM	27	1287.00	TQEX
GENMAB A/S	15-Apr-2025	4:42:01 PM	7	1287.50	CEUX
GENMAB A/S	15-Apr-2025	4:42:01 PM	7	1287.50	CEUX
GENMAB A/S	15-Apr-2025	4:42:01 PM	17	1287.50	CEUX
GENMAB A/S	15-Apr-2025	4:42:01 PM	35	1287.50	CEUX
GENMAB A/S	15-Apr-2025	4:42:01 PM	11	1287.50	CEUX
GENMAB A/S	15-Apr-2025	4:42:02 PM	8	1287.50	CEUX
GENMAB A/S	15-Apr-2025	4:42:02 PM	7	1287.50	CEUX
GENMAB A/S	15-Apr-2025	4:42:02 PM	13	1287.50	CEUX
GENMAB A/S	15-Apr-2025	4:42:07 PM	6	1286.50	CEUX
GENMAB A/S	15-Apr-2025	4:42:07 PM	10	1287.00	AQEU
GENMAB A/S	15-Apr-2025	4:42:07 PM	10	1287.00	AQEU
GENMAB A/S	15-Apr-2025	4:42:07 PM	10	1287.00	AQEU

138

Exhibit 99.1(a)

APPENDIX Share buy-back programme - Specification for April 14 – April 18, 2025

GENMAB A/S	15-Apr-2025	4:42:07 PM	4	1287.00	AQEU
GENMAB A/S	15-Apr-2025	4:42:16 PM	8	1287.00	CEUX
GENMAB A/S	15-Apr-2025	4:42:16 PM	25	1287.00	CEUX
GENMAB A/S	15-Apr-2025	4:42:16 PM	25	1287.00	CEUX
GENMAB A/S	15-Apr-2025	4:42:21 PM	66	1286.50	XCSE
GENMAB A/S	15-Apr-2025	4:42:29 PM	10	1287.00	TQEX
GENMAB A/S	15-Apr-2025	4:42:29 PM	6	1287.00	TQEX
GENMAB A/S	15-Apr-2025	4:42:29 PM	2	1287.00	TQEX
GENMAB A/S	15-Apr-2025	4:42:29 PM	3	1287.00	TQEX
GENMAB A/S	15-Apr-2025	4:42:29 PM	6	1287.00	TQEX
GENMAB A/S	15-Apr-2025	4:42:29 PM	5	1287.00	TQEX
GENMAB A/S	15-Apr-2025	4:42:29 PM	1	1287.00	TQEX
GENMAB A/S	15-Apr-2025	4:42:46 PM	57	1287.00	XCSE
GENMAB A/S	15-Apr-2025	4:42:46 PM	19	1287.00	XCSE
GENMAB A/S	15-Apr-2025	4:42:46 PM	27	1287.00	XCSE
GENMAB A/S	15-Apr-2025	4:42:46 PM	19	1287.00	CEUX
GENMAB A/S	15-Apr-2025	4:42:46 PM	18	1287.00	CEUX
GENMAB A/S	15-Apr-2025	4:42:46 PM	14	1287.00	CEUX
GENMAB A/S	15-Apr-2025	4:42:47 PM	114	1287.00	XCSE
GENMAB A/S	15-Apr-2025	4:42:47 PM	13	1287.00	CEUX
GENMAB A/S	15-Apr-2025	4:43:01 PM	23	1286.50	XCSE
GENMAB A/S	15-Apr-2025	4:43:01 PM	51	1287.00	CEUX
GENMAB A/S	15-Apr-2025	4:43:31 PM	74	1287.00	XCSE
GENMAB A/S	15-Apr-2025	4:43:31 PM	50	1287.50	CEUX
GENMAB A/S	15-Apr-2025	4:43:31 PM	36	1287.50	CEUX
GENMAB A/S	15-Apr-2025	4:43:31 PM	26	1287.50	CEUX
GENMAB A/S	15-Apr-2025	4:43:37 PM	2	1288.00	XCSE
GENMAB A/S	15-Apr-2025	4:43:37 PM	5	1288.00	XCSE
GENMAB A/S	15-Apr-2025	4:43:37 PM	80	1288.00	XCSE
GENMAB A/S	15-Apr-2025	4:43:37 PM	8	1288.00	CEUX
GENMAB A/S	15-Apr-2025	4:43:37 PM	7	1288.00	CEUX
GENMAB A/S	15-Apr-2025	4:43:37 PM	5	1288.00	CEUX
GENMAB A/S	15-Apr-2025	4:43:37 PM	5	1288.00	CEUX
GENMAB A/S	15-Apr-2025	4:43:37 PM	2	1288.00	CEUX
GENMAB A/S	15-Apr-2025	4:43:37 PM	2	1288.00	AQEU
GENMAB A/S	15-Apr-2025	4:43:37 PM	10	1288.00	AQEU
GENMAB A/S	15-Apr-2025	4:43:37 PM	13	1288.00	AQEU
GENMAB A/S	15-Apr-2025	4:44:07 PM	24	1289.00	TQEX
GENMAB A/S	15-Apr-2025	4:44:07 PM	5	1289.00	TQEX
GENMAB A/S	15-Apr-2025	4:44:08 PM	87	1289.00	XCSE
GENMAB A/S	15-Apr-2025	4:44:08 PM	2	1289.00	CEUX
GENMAB A/S	15-Apr-2025	4:44:08 PM	15	1289.00	CEUX
GENMAB A/S	15-Apr-2025	4:44:08 PM	19	1289.00	CEUX

139

Exhibit 99.1(a)

APPENDIX Share buy-back programme - Specification for April 14 – April 18, 2025

GENMAB A/S	15-Apr-2025	4:44:08 PM	7	1289.00	CEUX
GENMAB A/S	15-Apr-2025	4:44:08 PM	21	1289.00	CEUX
GENMAB A/S	15-Apr-2025	4:44:41 PM	36	1289.00	CEUX
GENMAB A/S	15-Apr-2025	4:44:41 PM	25	1289.00	AQEU
GENMAB A/S	15-Apr-2025	4:44:45 PM	35	1289.00	XCSE
GENMAB A/S	15-Apr-2025	4:44:45 PM	22	1289.00	XCSE
GENMAB A/S	15-Apr-2025	4:44:45 PM	57	1289.00	XCSE
GENMAB A/S	15-Apr-2025	4:44:45 PM	32	1289.00	CEUX
GENMAB A/S	15-Apr-2025	4:44:46 PM	18	1289.00	XCSE
GENMAB A/S	15-Apr-2025	4:44:46 PM	19	1289.00	XCSE
GENMAB A/S	15-Apr-2025	4:44:46 PM	35	1289.00	XCSE
GENMAB A/S	15-Apr-2025	4:44:46 PM	19	1289.00	XCSE
GENMAB A/S	15-Apr-2025	4:44:46 PM	35	1289.00	XCSE
GENMAB A/S	15-Apr-2025	4:44:46 PM	15	1289.00	XCSE
GENMAB A/S	15-Apr-2025	4:44:46 PM	18	1289.00	XCSE
GENMAB A/S	15-Apr-2025	4:44:46 PM	16	1289.00	XCSE
GENMAB A/S	15-Apr-2025	4:44:46 PM	30	1289.00	XCSE
GENMAB A/S	15-Apr-2025	4:44:53 PM	45	1289.00	XCSE
GENMAB A/S	15-Apr-2025	4:44:53 PM	12	1289.00	XCSE
GENMAB A/S	15-Apr-2025	4:44:53 PM	2	1289.00	TQEX
GENMAB A/S	15-Apr-2025	4:44:53 PM	8	1289.00	TQEX
GENMAB A/S	15-Apr-2025	4:44:53 PM	15	1289.00	TQEX
GENMAB A/S	15-Apr-2025	4:44:53 PM	12	1289.00	CEUX
GENMAB A/S	15-Apr-2025	4:44:53 PM	13	1289.00	CEUX
GENMAB A/S	15-Apr-2025	4:44:53 PM	6	1289.00	CEUX
GENMAB A/S	15-Apr-2025	4:44:53 PM	28	1289.00	CEUX
GENMAB A/S	15-Apr-2025	4:44:53 PM	3	1289.00	CEUX
GENMAB A/S	15-Apr-2025	4:44:53 PM	11	1289.00	CEUX
GENMAB A/S	15-Apr-2025	4:44:53 PM	3	1289.00	CEUX
GENMAB A/S	15-Apr-2025	4:44:53 PM	7	1289.00	CEUX
GENMAB A/S	15-Apr-2025	4:45:09 PM	10	1289.50	CEUX
GENMAB A/S	15-Apr-2025	4:45:09 PM	32	1289.50	CEUX
GENMAB A/S	15-Apr-2025	4:45:10 PM	35	1289.50	XCSE
GENMAB A/S	15-Apr-2025	4:45:14 PM	25	1289.50	CEUX
GENMAB A/S	15-Apr-2025	4:45:15 PM	49	1289.50	XCSE
GENMAB A/S	15-Apr-2025	4:45:15 PM	35	1289.50	XCSE
GENMAB A/S	15-Apr-2025	4:45:15 PM	30	1289.50	XCSE
GENMAB A/S	15-Apr-2025	4:45:22 PM	57	1290.00	XCSE
GENMAB A/S	15-Apr-2025	4:45:22 PM	19	1290.00	XCSE
GENMAB A/S	15-Apr-2025	4:45:22 PM	9	1290.00	XCSE
GENMAB A/S	15-Apr-2025	4:45:22 PM	2	1290.00	XCSE
GENMAB A/S	15-Apr-2025	4:45:22 PM	2	1289.50	CEUX
GENMAB A/S	15-Apr-2025	4:45:22 PM	5	1289.50	CEUX

140

Exhibit 99.1(a)

APPENDIX Share buy-back programme - Specification for April 14 – April 18, 2025

GENMAB A/S	15-Apr-2025	4:45:22 PM	7	1289.50	CEUX
GENMAB A/S	15-Apr-2025	4:45:26 PM	35	1290.00	XCSE
GENMAB A/S	15-Apr-2025	4:45:26 PM	15	1290.00	XCSE
GENMAB A/S	15-Apr-2025	4:45:26 PM	35	1290.00	XCSE
GENMAB A/S	15-Apr-2025	4:45:26 PM	29	1290.00	XCSE
GENMAB A/S	15-Apr-2025	4:45:26 PM	3	1289.50	CEUX
GENMAB A/S	15-Apr-2025	4:45:26 PM	17	1289.50	CEUX
GENMAB A/S	15-Apr-2025	4:45:29 PM	2	1290.00	XCSE
GENMAB A/S	15-Apr-2025	4:45:54 PM	32	1290.50	CEUX
GENMAB A/S	15-Apr-2025	4:45:56 PM	19	1290.50	XCSE
GENMAB A/S	15-Apr-2025	4:45:56 PM	23	1290.50	XCSE
GENMAB A/S	15-Apr-2025	4:45:56 PM	57	1290.50	XCSE
GENMAB A/S	15-Apr-2025	4:45:56 PM	15	1290.50	XCSE
GENMAB A/S	15-Apr-2025	4:45:59 PM	24	1291.00	XCSE
GENMAB A/S	15-Apr-2025	4:45:59 PM	57	1291.00	XCSE
GENMAB A/S	15-Apr-2025	4:45:59 PM	2	1290.50	TQEX
GENMAB A/S	15-Apr-2025	4:46:00 PM	57	1291.00	XCSE
GENMAB A/S	15-Apr-2025	4:46:00 PM	15	1291.00	XCSE
GENMAB A/S	15-Apr-2025	4:46:03 PM	42	1291.00	CEUX
GENMAB A/S	15-Apr-2025	4:46:03 PM	9	1291.00	CEUX
GENMAB A/S	15-Apr-2025	4:46:07 PM	5	1291.00	XCSE
GENMAB A/S	15-Apr-2025	4:46:07 PM	3	1290.50	TQEX
GENMAB A/S	15-Apr-2025	4:46:07 PM	36	1290.50	TQEX
GENMAB A/S	15-Apr-2025	4:46:07 PM	42	1290.50	CEUX
GENMAB A/S	15-Apr-2025	4:46:07 PM	30	1290.50	AQEU
GENMAB A/S	15-Apr-2025	4:46:13 PM	71	1291.00	XCSE
GENMAB A/S	15-Apr-2025	4:46:13 PM	32	1291.00	CEUX
GENMAB A/S	15-Apr-2025	4:46:13 PM	28	1291.00	AQEU
GENMAB A/S	15-Apr-2025	4:46:14 PM	2	1291.00	XCSE
GENMAB A/S	15-Apr-2025	4:46:14 PM	2	1291.00	XCSE
GENMAB A/S	15-Apr-2025	4:46:14 PM	2	1291.00	XCSE
GENMAB A/S	15-Apr-2025	4:46:14 PM	3	1291.00	XCSE
GENMAB A/S	15-Apr-2025	4:46:15 PM	29	1291.00	CEUX
GENMAB A/S	15-Apr-2025	4:46:17 PM	87	1290.00	XCSE
GENMAB A/S	15-Apr-2025	4:46:17 PM	1	1289.00	XCSE
GENMAB A/S	15-Apr-2025	4:46:17 PM	49	1290.00	XCSE
GENMAB A/S	15-Apr-2025	4:46:17 PM	17	1290.00	XCSE
GENMAB A/S	15-Apr-2025	4:46:17 PM	18	1290.00	XCSE
GENMAB A/S	15-Apr-2025	4:46:17 PM	15	1290.00	XCSE
GENMAB A/S	15-Apr-2025	4:46:17 PM	26	1289.50	CEUX
GENMAB A/S	15-Apr-2025	4:46:18 PM	5	1289.00	XCSE
GENMAB A/S	15-Apr-2025	4:46:18 PM	11	1289.00	XCSE
GENMAB A/S	15-Apr-2025	4:46:18 PM	4	1289.00	XCSE

141

Exhibit 99.1(a)

APPENDIX Share buy-back programme - Specification for April 14 – April 18, 2025

GENMAB A/S	15-Apr-2025	4:46:18 PM	11	1289.00	XCSE
GENMAB A/S	15-Apr-2025	4:46:18 PM	25	1289.00	CEUX
GENMAB A/S	15-Apr-2025	4:46:42 PM	35	1290.00	XCSE
GENMAB A/S	15-Apr-2025	4:46:50 PM	40	1290.50	XCSE
GENMAB A/S	15-Apr-2025	4:46:50 PM	39	1290.50	TQEX
GENMAB A/S	15-Apr-2025	4:47:00 PM	32	1291.00	XCSE
GENMAB A/S	15-Apr-2025	4:47:00 PM	11	1291.00	XCSE
GENMAB A/S	15-Apr-2025	4:47:00 PM	48	1291.00	CEUX
GENMAB A/S	15-Apr-2025	4:47:01 PM	18	1291.00	XCSE
GENMAB A/S	15-Apr-2025	4:47:01 PM	7	1291.00	XCSE
GENMAB A/S	15-Apr-2025	4:47:11 PM	28	1290.50	AQEU
GENMAB A/S	15-Apr-2025	4:47:12 PM	42	1290.00	CEUX
GENMAB A/S	15-Apr-2025	4:47:29 PM	30	1289.50	XCSE
GENMAB A/S	15-Apr-2025	4:47:30 PM	15	1290.00	XCSE
GENMAB A/S	15-Apr-2025	4:48:07 PM	35	1290.50	XCSE
GENMAB A/S	15-Apr-2025	4:48:07 PM	28	1290.50	XCSE
GENMAB A/S	15-Apr-2025	4:48:07 PM	15	1290.50	XCSE
GENMAB A/S	15-Apr-2025	4:48:07 PM	15	1290.50	XCSE
GENMAB A/S	15-Apr-2025	4:48:07 PM	21	1290.50	XCSE
GENMAB A/S	15-Apr-2025	4:48:07 PM	38	1290.50	CEUX
GENMAB A/S	15-Apr-2025	4:48:07 PM	29	1290.50	CEUX
GENMAB A/S	15-Apr-2025	4:48:16 PM	2	1290.00	XCSE
GENMAB A/S	15-Apr-2025	4:48:21 PM	88	1290.00	XCSE
GENMAB A/S	15-Apr-2025	4:48:21 PM	61	1290.00	CEUX
GENMAB A/S	15-Apr-2025	4:48:21 PM	10	1290.00	AQEU
GENMAB A/S	15-Apr-2025	4:48:27 PM	36	1290.00	CEUX
GENMAB A/S	15-Apr-2025	4:48:27 PM	7	1290.00	CEUX
GENMAB A/S	15-Apr-2025	4:48:27 PM	7	1290.00	CEUX
GENMAB A/S	15-Apr-2025	4:48:27 PM	29	1290.00	AQEU
GENMAB A/S	15-Apr-2025	4:48:28 PM	19	1290.00	XCSE
GENMAB A/S	15-Apr-2025	4:48:28 PM	15	1290.00	XCSE
GENMAB A/S	15-Apr-2025	4:48:28 PM	19	1290.00	XCSE
GENMAB A/S	15-Apr-2025	4:48:28 PM	15	1290.00	XCSE
GENMAB A/S	15-Apr-2025	4:48:41 PM	15	1290.50	XCSE
GENMAB A/S	15-Apr-2025	4:48:41 PM	19	1290.50	XCSE
GENMAB A/S	15-Apr-2025	4:48:41 PM	88	1290.00	XCSE
GENMAB A/S	15-Apr-2025	4:48:49 PM	64	1290.00	CEUX
GENMAB A/S	15-Apr-2025	4:48:52 PM	25	1290.00	TQEX
GENMAB A/S	15-Apr-2025	4:48:53 PM	57	1290.00	XCSE
GENMAB A/S	15-Apr-2025	4:48:53 PM	19	1290.00	XCSE
GENMAB A/S	15-Apr-2025	4:48:53 PM	19	1290.00	XCSE
GENMAB A/S	15-Apr-2025	4:49:01 PM	22	1290.00	CEUX
GENMAB A/S	15-Apr-2025	4:50:08 PM	36	1289.50	CEUX

142

Exhibit 99.1(a)

APPENDIX Share buy-back programme - Specification for April 14 – April 18, 2025

GENMAB A/S	15-Apr-2025	4:50:08 PM	31	1289.00	CEUX
GENMAB A/S	15-Apr-2025	4:50:17 PM	36	1289.50	CEUX
GENMAB A/S	15-Apr-2025	4:50:17 PM	8	1289.50	CEUX
GENMAB A/S	15-Apr-2025	4:50:17 PM	8	1289.50	CEUX
GENMAB A/S	15-Apr-2025	4:50:18 PM	20	1289.50	CEUX
GENMAB A/S	15-Apr-2025	4:50:31 PM	36	1289.50	CEUX
GENMAB A/S	15-Apr-2025	4:50:37 PM	13	1289.50	XCSE
GENMAB A/S	15-Apr-2025	4:50:38 PM	16	1289.50	CEUX
GENMAB A/S	15-Apr-2025	4:50:40 PM	7	1289.50	XCSE
GENMAB A/S	15-Apr-2025	4:50:44 PM	15	1289.50	XCSE
GENMAB A/S	15-Apr-2025	4:50:46 PM	10	1289.50	XCSE
GENMAB A/S	15-Apr-2025	4:50:46 PM	17	1289.50	XCSE
GENMAB A/S	15-Apr-2025	4:50:46 PM	19	1289.50	XCSE
GENMAB A/S	15-Apr-2025	4:50:46 PM	15	1289.50	XCSE
GENMAB A/S	15-Apr-2025	4:50:46 PM	34	1289.50	XCSE
GENMAB A/S	15-Apr-2025	4:50:46 PM	8	1289.50	CEUX
GENMAB A/S	15-Apr-2025	4:50:46 PM	8	1289.50	CEUX
GENMAB A/S	15-Apr-2025	4:50:46 PM	22	1289.50	CEUX
GENMAB A/S	15-Apr-2025	4:50:48 PM	15	1289.00	XCSE
GENMAB A/S	15-Apr-2025	4:50:48 PM	17	1289.00	XCSE
GENMAB A/S	15-Apr-2025	4:50:48 PM	36	1289.00	XCSE
GENMAB A/S	15-Apr-2025	4:50:48 PM	46	1289.00	XCSE
GENMAB A/S	15-Apr-2025	4:50:48 PM	42	1288.50	XCSE
GENMAB A/S	15-Apr-2025	4:50:48 PM	36	1289.00	CEUX
GENMAB A/S	15-Apr-2025	4:50:48 PM	21	1289.00	CEUX
GENMAB A/S	15-Apr-2025	4:50:48 PM	26	1289.00	CEUX
GENMAB A/S	15-Apr-2025	4:50:48 PM	99	1289.00	CEUX
GENMAB A/S	15-Apr-2025	4:50:49 PM	1	1288.50	XCSE
GENMAB A/S	15-Apr-2025	4:50:49 PM	30	1288.50	TQEX
GENMAB A/S	15-Apr-2025	4:50:49 PM	25	1288.50	AQEU
GENMAB A/S	15-Apr-2025	4:50:49 PM	4	1288.50	AQEU
GENMAB A/S	15-Apr-2025	4:50:49 PM	4	1288.50	AQEU
GENMAB A/S	15-Apr-2025	4:50:50 PM	6	1288.50	AQEU
GENMAB A/S	15-Apr-2025	4:51:01 PM	26	1289.00	TQEX
GENMAB A/S	15-Apr-2025	4:51:01 PM	38	1289.00	CEUX
GENMAB A/S	15-Apr-2025	4:51:03 PM	11	1289.00	TQEX
GENMAB A/S	15-Apr-2025	4:51:07 PM	17	1290.00	XCSE
GENMAB A/S	15-Apr-2025	4:51:07 PM	18	1290.00	XCSE
GENMAB A/S	15-Apr-2025	4:51:08 PM	19	1290.00	XCSE
GENMAB A/S	15-Apr-2025	4:51:08 PM	57	1290.00	XCSE
GENMAB A/S	15-Apr-2025	4:51:08 PM	19	1290.00	XCSE
GENMAB A/S	15-Apr-2025	4:51:08 PM	19	1290.00	XCSE
GENMAB A/S	15-Apr-2025	4:51:09 PM	27	1290.00	CEUX

143

Exhibit 99.1(a)

APPENDIX Share buy-back programme - Specification for April 14 – April 18, 2025

GENMAB A/S	15-Apr-2025	4:51:12 PM	15	1290.00	XCSE
GENMAB A/S	15-Apr-2025	4:51:13 PM	19	1290.00	XCSE
GENMAB A/S	15-Apr-2025	4:51:13 PM	18	1290.00	XCSE
GENMAB A/S	15-Apr-2025	4:51:13 PM	16	1290.00	CEUX
GENMAB A/S	15-Apr-2025	4:51:19 PM	32	1290.00	CEUX
GENMAB A/S	15-Apr-2025	4:51:20 PM	46	1289.50	XCSE
GENMAB A/S	15-Apr-2025	4:51:24 PM	31	1290.00	CEUX
GENMAB A/S	15-Apr-2025	4:51:35 PM	85	1290.50	XCSE
GENMAB A/S	15-Apr-2025	4:51:35 PM	36	1290.50	CEUX
GENMAB A/S	15-Apr-2025	4:51:40 PM	20	1290.50	TQEX
GENMAB A/S	15-Apr-2025	4:51:40 PM	13	1290.50	TQEX
GENMAB A/S	15-Apr-2025	4:51:47 PM	7	1290.50	AQEU
GENMAB A/S	15-Apr-2025	4:51:49 PM	5	1291.00	CEUX
GENMAB A/S	15-Apr-2025	4:51:53 PM	18	1291.00	CEUX
GENMAB A/S	15-Apr-2025	4:52:01 PM	18	1291.50	CEUX
GENMAB A/S	15-Apr-2025	4:52:02 PM	5	1291.50	XCSE
GENMAB A/S	15-Apr-2025	4:52:02 PM	5	1291.50	XCSE
GENMAB A/S	15-Apr-2025	4:52:02 PM	15	1291.50	XCSE
GENMAB A/S	15-Apr-2025	4:52:02 PM	2	1291.50	XCSE
GENMAB A/S	15-Apr-2025	4:52:02 PM	12	1291.50	CEUX
GENMAB A/S	15-Apr-2025	4:52:07 PM	3	1292.00	XCSE
GENMAB A/S	15-Apr-2025	4:52:28 PM	9	1292.00	CEUX
GENMAB A/S	15-Apr-2025	4:52:28 PM	38	1292.00	CEUX
GENMAB A/S	15-Apr-2025	4:52:28 PM	6	1292.00	CEUX
GENMAB A/S	15-Apr-2025	4:52:41 PM	36	1292.00	CEUX
GENMAB A/S	15-Apr-2025	4:52:42 PM	36	1292.00	CEUX
GENMAB A/S	15-Apr-2025	4:52:45 PM	17	1292.00	XCSE
GENMAB A/S	15-Apr-2025	4:52:45 PM	19	1292.00	XCSE
GENMAB A/S	15-Apr-2025	4:52:45 PM	15	1292.00	XCSE
GENMAB A/S	15-Apr-2025	4:52:45 PM	57	1292.00	XCSE
GENMAB A/S	15-Apr-2025	4:52:45 PM	6	1292.00	XCSE
GENMAB A/S	15-Apr-2025	4:52:45 PM	36	1292.00	CEUX
GENMAB A/S	15-Apr-2025	4:52:46 PM	57	1292.00	XCSE
GENMAB A/S	15-Apr-2025	4:52:46 PM	13	1292.00	XCSE
GENMAB A/S	15-Apr-2025	4:52:46 PM	16	1292.00	XCSE
GENMAB A/S	15-Apr-2025	4:52:46 PM	19	1292.00	XCSE
GENMAB A/S	15-Apr-2025	4:52:46 PM	17	1292.00	XCSE
GENMAB A/S	15-Apr-2025	4:52:46 PM	13	1292.00	XCSE
GENMAB A/S	15-Apr-2025	4:52:46 PM	16	1292.00	XCSE
GENMAB A/S	15-Apr-2025	4:52:46 PM	57	1292.00	XCSE
GENMAB A/S	15-Apr-2025	4:52:46 PM	17	1292.00	XCSE
GENMAB A/S	15-Apr-2025	4:52:46 PM	21	1292.00	XCSE
GENMAB A/S	15-Apr-2025	4:52:46 PM	19	1292.00	XCSE

144

Exhibit 99.1(a)

APPENDIX Share buy-back programme - Specification for April 14 – April 18, 2025

GENMAB A/S	15-Apr-2025	4:52:46 PM	57	1292.00	XCSE
GENMAB A/S	15-Apr-2025	4:52:47 PM	27	1292.00	XCSE
GENMAB A/S	15-Apr-2025	4:52:47 PM	57	1292.00	XCSE
GENMAB A/S	15-Apr-2025	4:52:47 PM	18	1292.00	XCSE
GENMAB A/S	15-Apr-2025	4:52:47 PM	13	1292.00	XCSE
GENMAB A/S	15-Apr-2025	4:52:47 PM	17	1292.00	XCSE
GENMAB A/S	15-Apr-2025	4:52:47 PM	57	1292.00	XCSE
GENMAB A/S	15-Apr-2025	4:52:48 PM	17	1292.00	XCSE
GENMAB A/S	15-Apr-2025	4:52:48 PM	18	1292.00	XCSE
GENMAB A/S	15-Apr-2025	4:52:48 PM	57	1292.00	XCSE
GENMAB A/S	15-Apr-2025	4:52:48 PM	17	1292.00	XCSE
GENMAB A/S	15-Apr-2025	4:52:48 PM	5	1292.00	XCSE
GENMAB A/S	15-Apr-2025	4:52:49 PM	16	1292.00	XCSE
GENMAB A/S	15-Apr-2025	4:52:49 PM	16	1292.00	XCSE
GENMAB A/S	15-Apr-2025	4:52:49 PM	57	1292.00	XCSE
GENMAB A/S	15-Apr-2025	4:52:49 PM	18	1292.00	XCSE
GENMAB A/S	15-Apr-2025	4:52:49 PM	12	1292.00	CEUX
GENMAB A/S	15-Apr-2025	4:52:49 PM	40	1292.00	CEUX
GENMAB A/S	15-Apr-2025	4:52:53 PM	36	1292.00	CEUX
GENMAB A/S	15-Apr-2025	4:52:53 PM	11	1292.00	CEUX
GENMAB A/S	15-Apr-2025	4:52:56 PM	57	1291.50	XCSE
GENMAB A/S	15-Apr-2025	4:52:56 PM	10	1291.50	XCSE
GENMAB A/S	15-Apr-2025	4:52:56 PM	19	1291.50	XCSE
GENMAB A/S	15-Apr-2025	4:52:56 PM	55	1291.00	XCSE
GENMAB A/S	15-Apr-2025	4:52:56 PM	33	1291.50	AQEU
GENMAB A/S	15-Apr-2025	4:52:56 PM	13	1291.50	AQEU
GENMAB A/S	15-Apr-2025	4:52:59 PM	33	1291.00	XCSE
GENMAB A/S	15-Apr-2025	4:53:02 PM	6	1291.50	XCSE
GENMAB A/S	15-Apr-2025	4:53:03 PM	3	1291.50	CEUX
GENMAB A/S	15-Apr-2025	4:53:03 PM	5	1291.50	CEUX
GENMAB A/S	15-Apr-2025	4:53:03 PM	12	1291.50	CEUX
GENMAB A/S	15-Apr-2025	4:53:06 PM	46	1291.50	XCSE
GENMAB A/S	15-Apr-2025	4:53:21 PM	18	1291.50	XCSE
GENMAB A/S	15-Apr-2025	4:53:21 PM	28	1292.50	CEUX
GENMAB A/S	15-Apr-2025	4:53:26 PM	34	1293.00	XCSE
GENMAB A/S	15-Apr-2025	4:53:26 PM	57	1293.00	XCSE
GENMAB A/S	15-Apr-2025	4:53:26 PM	13	1293.00	XCSE
GENMAB A/S	15-Apr-2025	4:53:26 PM	8	1292.50	CEUX
GENMAB A/S	15-Apr-2025	4:53:26 PM	7	1292.50	CEUX
GENMAB A/S	15-Apr-2025	4:53:41 PM	80	1292.00	XCSE
GENMAB A/S	15-Apr-2025	4:54:01 PM	5	1292.00	XCSE
GENMAB A/S	15-Apr-2025	4:54:01 PM	27	1292.00	TQEX
GENMAB A/S	15-Apr-2025	4:54:01 PM	6	1291.50	TQEX

145

Exhibit 99.1(a)

APPENDIX Share buy-back programme - Specification for April 14 – April 18, 2025

GENMAB A/S	15-Apr-2025	4:54:01 PM	2	1291.50	TQEX
GENMAB A/S	15-Apr-2025	4:54:01 PM	4	1291.50	TQEX
GENMAB A/S	15-Apr-2025	4:54:01 PM	2	1291.50	TQEX
GENMAB A/S	15-Apr-2025	4:54:01 PM	9	1291.50	TQEX
GENMAB A/S	15-Apr-2025	4:54:01 PM	2	1291.50	TQEX
GENMAB A/S	15-Apr-2025	4:54:01 PM	25	1292.00	CEUX
GENMAB A/S	15-Apr-2025	4:54:01 PM	7	1291.50	CEUX
GENMAB A/S	15-Apr-2025	4:54:01 PM	3	1291.50	CEUX
GENMAB A/S	15-Apr-2025	4:54:01 PM	2	1291.50	CEUX
GENMAB A/S	15-Apr-2025	4:54:01 PM	14	1291.50	CEUX
GENMAB A/S	15-Apr-2025	4:54:01 PM	6	1291.50	AQEU
GENMAB A/S	15-Apr-2025	4:54:01 PM	12	1291.50	AQEU
GENMAB A/S	15-Apr-2025	4:54:07 PM	1	1291.50	AQEU
GENMAB A/S	15-Apr-2025	4:54:12 PM	29	1291.50	XCSE
GENMAB A/S	15-Apr-2025	4:54:12 PM	19	1291.50	XCSE
GENMAB A/S	15-Apr-2025	4:54:12 PM	17	1291.50	XCSE
GENMAB A/S	15-Apr-2025	4:54:12 PM	35	1291.50	XCSE
GENMAB A/S	15-Apr-2025	4:54:12 PM	8	1291.50	CEUX
GENMAB A/S	15-Apr-2025	4:54:12 PM	8	1291.50	CEUX
GENMAB A/S	15-Apr-2025	4:54:12 PM	8	1291.50	CEUX
GENMAB A/S	15-Apr-2025	4:54:12 PM	8	1291.50	CEUX
GENMAB A/S	15-Apr-2025	4:54:12 PM	28	1291.50	CEUX
GENMAB A/S	15-Apr-2025	4:54:12 PM	12	1291.50	CEUX
GENMAB A/S	15-Apr-2025	4:54:12 PM	5	1291.50	CEUX
GENMAB A/S	15-Apr-2025	4:54:12 PM	21	1291.50	CEUX
GENMAB A/S	15-Apr-2025	4:54:12 PM	7	1291.50	CEUX
GENMAB A/S	15-Apr-2025	4:54:12 PM	8	1291.50	CEUX
GENMAB A/S	15-Apr-2025	4:54:12 PM	7	1291.50	CEUX
GENMAB A/S	15-Apr-2025	4:54:12 PM	17	1291.50	AQEU
GENMAB A/S	15-Apr-2025	4:54:13 PM	29	1291.50	XCSE
GENMAB A/S	15-Apr-2025	4:54:13 PM	19	1291.50	XCSE
GENMAB A/S	15-Apr-2025	4:54:13 PM	16	1291.50	XCSE
GENMAB A/S	15-Apr-2025	4:54:18 PM	18	1292.50	XCSE
GENMAB A/S	15-Apr-2025	4:54:18 PM	18	1292.50	XCSE
GENMAB A/S	15-Apr-2025	4:54:18 PM	35	1292.50	XCSE
GENMAB A/S	15-Apr-2025	4:54:18 PM	16	1292.50	XCSE
GENMAB A/S	15-Apr-2025	4:54:18 PM	27	1292.50	XCSE
GENMAB A/S	15-Apr-2025	4:54:18 PM	30	1292.50	XCSE
GENMAB A/S	15-Apr-2025	4:54:18 PM	16	1292.50	XCSE
GENMAB A/S	15-Apr-2025	4:54:18 PM	14	1292.50	XCSE
GENMAB A/S	15-Apr-2025	4:54:18 PM	10	1292.50	XCSE
GENMAB A/S	15-Apr-2025	4:54:31 PM	26	1291.50	TQEX
GENMAB A/S	15-Apr-2025	4:54:49 PM	33	1292.50	XCSE

146

Exhibit 99.1(a)

APPENDIX Share buy-back programme - Specification for April 14 – April 18, 2025

GENMAB A/S	15-Apr-2025	4:54:49 PM	32	1292.50	CEUX
GENMAB A/S	15-Apr-2025	4:54:50 PM	37	1292.00	AQEU
GENMAB A/S	16-Apr-2025	9:35:44 AM	81	1289.00	XCSE
GENMAB A/S	16-Apr-2025	9:35:44 AM	32	1289.00	CEUX
GENMAB A/S	16-Apr-2025	9:35:44 AM	58	1289.00	CEUX
GENMAB A/S	16-Apr-2025	9:39:30 AM	39	1290.00	XCSE
GENMAB A/S	16-Apr-2025	9:39:30 AM	88	1290.50	TQEX
GENMAB A/S	16-Apr-2025	9:39:30 AM	29	1289.50	CEUX
GENMAB A/S	16-Apr-2025	9:39:30 AM	21	1290.50	AQEU
GENMAB A/S	16-Apr-2025	9:39:30 AM	65	1290.50	AQEU
GENMAB A/S	16-Apr-2025	9:39:30 AM	82	1289.50	AQEU
GENMAB A/S	16-Apr-2025	9:42:18 AM	15	1289.00	XCSE
GENMAB A/S	16-Apr-2025	9:42:18 AM	37	1289.00	XCSE
GENMAB A/S	16-Apr-2025	9:42:18 AM	75	1289.00	TQEX
GENMAB A/S	16-Apr-2025	9:43:05 AM	16	1289.00	XCSE
GENMAB A/S	16-Apr-2025	9:43:05 AM	10	1289.00	XCSE
GENMAB A/S	16-Apr-2025	9:43:05 AM	48	1289.50	CEUX
GENMAB A/S	16-Apr-2025	9:43:05 AM	28	1289.50	AQEU
GENMAB A/S	16-Apr-2025	9:43:09 AM	20	1289.00	TQEX
GENMAB A/S	16-Apr-2025	9:43:09 AM	16	1289.00	TQEX
GENMAB A/S	16-Apr-2025	9:43:13 AM	61	1288.50	CEUX
GENMAB A/S	16-Apr-2025	9:44:29 AM	11	1289.50	AQEU
GENMAB A/S	16-Apr-2025	9:44:32 AM	39	1289.50	XCSE
GENMAB A/S	16-Apr-2025	9:44:32 AM	20	1289.50	AQEU
GENMAB A/S	16-Apr-2025	9:45:04 AM	20	1289.00	CEUX
GENMAB A/S	16-Apr-2025	9:45:14 AM	43	1289.50	XCSE
GENMAB A/S	16-Apr-2025	9:46:28 AM	24	1289.00	CEUX
GENMAB A/S	16-Apr-2025	9:46:33 AM	19	1289.00	TQEX
GENMAB A/S	16-Apr-2025	9:46:33 AM	9	1289.00	TQEX
GENMAB A/S	16-Apr-2025	9:46:33 AM	12	1289.00	CEUX
GENMAB A/S	16-Apr-2025	9:49:04 AM	38	1288.50	XCSE
GENMAB A/S	16-Apr-2025	9:49:13 AM	37	1287.50	XCSE
GENMAB A/S	16-Apr-2025	9:49:13 AM	27	1287.50	CEUX
GENMAB A/S	16-Apr-2025	9:49:13 AM	4	1287.50	CEUX
GENMAB A/S	16-Apr-2025	9:49:25 AM	26	1286.50	XCSE
GENMAB A/S	16-Apr-2025	9:49:43 AM	33	1287.00	CEUX
GENMAB A/S	16-Apr-2025	9:49:43 AM	54	1287.00	CEUX
GENMAB A/S	16-Apr-2025	9:50:07 AM	64	1286.50	XCSE
GENMAB A/S	16-Apr-2025	9:50:24 AM	38	1286.00	CEUX
GENMAB A/S	16-Apr-2025	9:50:28 AM	27	1285.50	TQEX
GENMAB A/S	16-Apr-2025	9:51:02 AM	39	1285.00	XCSE
GENMAB A/S	16-Apr-2025	9:51:25 AM	21	1284.50	CEUX
GENMAB A/S	16-Apr-2025	9:51:59 AM	67	1284.50	CEUX

147

Exhibit 99.1(a)

APPENDIX Share buy-back programme - Specification for April 14 – April 18, 2025

GENMAB A/S	16-Apr-2025	9:52:00 AM	29	1284.50	TQEX
GENMAB A/S	16-Apr-2025	9:53:41 AM	45	1283.50	CEUX
GENMAB A/S	16-Apr-2025	9:56:20 AM	56	1283.50	XCSE
GENMAB A/S	16-Apr-2025	9:56:20 AM	46	1283.50	CEUX
GENMAB A/S	16-Apr-2025	9:56:29 AM	33	1283.00	TQEX
GENMAB A/S	16-Apr-2025	9:56:30 AM	23	1282.50	CEUX
GENMAB A/S	16-Apr-2025	9:56:44 AM	8	1283.00	TQEX
GENMAB A/S	16-Apr-2025	9:56:53 AM	88	1283.00	XCSE
GENMAB A/S	16-Apr-2025	9:56:53 AM	21	1283.00	TQEX
GENMAB A/S	16-Apr-2025	9:57:05 AM	67	1282.50	CEUX
GENMAB A/S	16-Apr-2025	9:58:25 AM	1	1282.00	XCSE
GENMAB A/S	16-Apr-2025	9:58:25 AM	1	1282.00	XCSE
GENMAB A/S	16-Apr-2025	9:58:25 AM	47	1282.00	XCSE
GENMAB A/S	16-Apr-2025	9:58:25 AM	28	1282.50	AQEU
GENMAB A/S	16-Apr-2025	9:58:29 AM	29	1282.00	TQEX
GENMAB A/S	16-Apr-2025	9:58:29 AM	32	1282.00	CEUX
GENMAB A/S	16-Apr-2025	9:58:29 AM	79	1281.50	CEUX
GENMAB A/S	16-Apr-2025	10:00:08 AM	92	1281.50	XCSE
GENMAB A/S	16-Apr-2025	10:00:19 AM	35	1281.00	TQEX
GENMAB A/S	16-Apr-2025	10:00:19 AM	15	1281.00	CEUX
GENMAB A/S	16-Apr-2025	10:00:19 AM	33	1281.00	AQEU
GENMAB A/S	16-Apr-2025	10:01:26 AM	91	1282.00	XCSE
GENMAB A/S	16-Apr-2025	10:01:26 AM	15	1282.50	CEUX
GENMAB A/S	16-Apr-2025	10:01:26 AM	13	1282.50	CEUX
GENMAB A/S	16-Apr-2025	10:01:28 AM	12	1282.50	CEUX
GENMAB A/S	16-Apr-2025	10:01:30 AM	61	1283.00	XCSE
GENMAB A/S	16-Apr-2025	10:02:26 AM	31	1283.00	XCSE
GENMAB A/S	16-Apr-2025	10:03:23 AM	36	1283.00	CEUX
GENMAB A/S	16-Apr-2025	10:03:23 AM	49	1283.00	CEUX
GENMAB A/S	16-Apr-2025	10:03:32 AM	38	1284.00	XCSE
GENMAB A/S	16-Apr-2025	10:03:32 AM	21	1284.00	XCSE
GENMAB A/S	16-Apr-2025	10:03:32 AM	35	1284.00	XCSE
GENMAB A/S	16-Apr-2025	10:03:59 AM	90	1284.00	XCSE
GENMAB A/S	16-Apr-2025	10:03:59 AM	7	1284.00	XCSE
GENMAB A/S	16-Apr-2025	10:03:59 AM	25	1284.00	XCSE
GENMAB A/S	16-Apr-2025	10:03:59 AM	41	1284.00	TQEX
GENMAB A/S	16-Apr-2025	10:03:59 AM	86	1284.00	CEUX
GENMAB A/S	16-Apr-2025	10:03:59 AM	25	1284.00	CEUX
GENMAB A/S	16-Apr-2025	10:03:59 AM	32	1284.00	CEUX
GENMAB A/S	16-Apr-2025	10:03:59 AM	36	1284.00	AQEU
GENMAB A/S	16-Apr-2025	10:03:59 AM	5	1284.00	AQEU
GENMAB A/S	16-Apr-2025	10:04:00 AM	23	1284.00	XCSE
GENMAB A/S	16-Apr-2025	10:04:35 AM	25	1284.00	XCSE

148

Exhibit 99.1(a)

APPENDIX Share buy-back programme - Specification for April 14 – April 18, 2025

GENMAB A/S	16-Apr-2025	10:04:48 AM	50	1284.00	XCSE
GENMAB A/S	16-Apr-2025	10:05:00 AM	35	1284.00	XCSE
GENMAB A/S	16-Apr-2025	10:05:00 AM	28	1284.00	XCSE
GENMAB A/S	16-Apr-2025	10:05:00 AM	38	1284.00	XCSE
GENMAB A/S	16-Apr-2025	10:05:00 AM	16	1284.00	XCSE
GENMAB A/S	16-Apr-2025	10:05:00 AM	14	1284.00	XCSE
GENMAB A/S	16-Apr-2025	10:05:00 AM	38	1284.00	XCSE
GENMAB A/S	16-Apr-2025	10:05:00 AM	25	1284.00	XCSE
GENMAB A/S	16-Apr-2025	10:05:36 AM	4	1283.00	AQEU
GENMAB A/S	16-Apr-2025	10:05:50 AM	90	1283.00	XCSE
GENMAB A/S	16-Apr-2025	10:05:50 AM	38	1283.00	XCSE
GENMAB A/S	16-Apr-2025	10:05:50 AM	15	1283.00	XCSE
GENMAB A/S	16-Apr-2025	10:05:50 AM	37	1283.00	XCSE
GENMAB A/S	16-Apr-2025	10:05:50 AM	88	1282.50	XCSE
GENMAB A/S	16-Apr-2025	10:05:50 AM	42	1283.00	TQEX
GENMAB A/S	16-Apr-2025	10:05:50 AM	88	1283.00	CEUX
GENMAB A/S	16-Apr-2025	10:05:50 AM	36	1283.00	CEUX
GENMAB A/S	16-Apr-2025	10:05:50 AM	76	1282.00	CEUX
GENMAB A/S	16-Apr-2025	10:05:50 AM	23	1283.00	AQEU
GENMAB A/S	16-Apr-2025	10:09:34 AM	26	1282.00	TQEX
GENMAB A/S	16-Apr-2025	10:09:34 AM	36	1282.50	CEUX
GENMAB A/S	16-Apr-2025	10:09:34 AM	10	1282.00	CEUX
GENMAB A/S	16-Apr-2025	10:09:34 AM	21	1282.00	AQEU
GENMAB A/S	16-Apr-2025	10:09:37 AM	5	1282.00	TQEX
GENMAB A/S	16-Apr-2025	10:09:43 AM	9	1282.00	AQEU
GENMAB A/S	16-Apr-2025	10:11:21 AM	3	1282.00	XCSE
GENMAB A/S	16-Apr-2025	10:11:21 AM	29	1282.00	XCSE
GENMAB A/S	16-Apr-2025	10:11:21 AM	19	1282.00	XCSE
GENMAB A/S	16-Apr-2025	10:11:22 AM	20	1282.00	CEUX
GENMAB A/S	16-Apr-2025	10:12:15 AM	90	1281.50	XCSE
GENMAB A/S	16-Apr-2025	10:14:29 AM	45	1281.50	XCSE
GENMAB A/S	16-Apr-2025	10:14:29 AM	10	1281.50	XCSE
GENMAB A/S	16-Apr-2025	10:14:29 AM	37	1281.50	XCSE
GENMAB A/S	16-Apr-2025	10:14:29 AM	22	1280.50	XCSE
GENMAB A/S	16-Apr-2025	10:14:29 AM	68	1280.50	XCSE
GENMAB A/S	16-Apr-2025	10:14:29 AM	31	1281.00	TQEX
GENMAB A/S	16-Apr-2025	10:14:29 AM	86	1280.50	CEUX
GENMAB A/S	16-Apr-2025	10:14:29 AM	28	1281.00	AQEU
GENMAB A/S	16-Apr-2025	10:14:30 AM	43	1280.00	XCSE
GENMAB A/S	16-Apr-2025	10:14:30 AM	45	1280.00	XCSE
GENMAB A/S	16-Apr-2025	10:14:30 AM	29	1280.00	XCSE
GENMAB A/S	16-Apr-2025	10:14:30 AM	45	1280.00	XCSE
GENMAB A/S	16-Apr-2025	10:14:30 AM	8	1280.00	XCSE

149

Exhibit 99.1(a)

APPENDIX Share buy-back programme - Specification for April 14 – April 18, 2025

GENMAB A/S	16-Apr-2025	10:14:30 AM	27	1279.50	TQEX
GENMAB A/S	16-Apr-2025	10:14:30 AM	36	1280.00	CEUX
GENMAB A/S	16-Apr-2025	10:14:30 AM	7	1280.00	CEUX
GENMAB A/S	16-Apr-2025	10:14:30 AM	7	1280.00	CEUX
GENMAB A/S	16-Apr-2025	10:14:30 AM	51	1280.00	CEUX
GENMAB A/S	16-Apr-2025	10:14:30 AM	88	1279.50	CEUX
GENMAB A/S	16-Apr-2025	10:14:30 AM	67	1279.50	CEUX
GENMAB A/S	16-Apr-2025	10:14:30 AM	29	1280.00	AQEU
GENMAB A/S	16-Apr-2025	10:14:53 AM	90	1280.00	XCSE
GENMAB A/S	16-Apr-2025	10:14:55 AM	92	1280.50	XCSE
GENMAB A/S	16-Apr-2025	10:14:55 AM	5	1280.50	XCSE
GENMAB A/S	16-Apr-2025	10:16:37 AM	45	1281.00	XCSE
GENMAB A/S	16-Apr-2025	10:16:37 AM	19	1281.00	XCSE
GENMAB A/S	16-Apr-2025	10:16:37 AM	37	1281.00	XCSE
GENMAB A/S	16-Apr-2025	10:16:37 AM	44	1280.50	XCSE
GENMAB A/S	16-Apr-2025	10:16:37 AM	30	1280.50	XCSE
GENMAB A/S	16-Apr-2025	10:16:37 AM	18	1280.50	XCSE
GENMAB A/S	16-Apr-2025	10:17:00 AM	26	1280.00	TQEX
GENMAB A/S	16-Apr-2025	10:17:00 AM	25	1280.00	CEUX
GENMAB A/S	16-Apr-2025	10:17:00 AM	36	1280.50	CEUX
GENMAB A/S	16-Apr-2025	10:17:00 AM	7	1280.50	CEUX
GENMAB A/S	16-Apr-2025	10:17:00 AM	6	1280.50	CEUX
GENMAB A/S	16-Apr-2025	10:17:00 AM	25	1279.50	CEUX
GENMAB A/S	16-Apr-2025	10:17:41 AM	89	1279.00	XCSE
GENMAB A/S	16-Apr-2025	10:17:41 AM	90	1278.00	XCSE
GENMAB A/S	16-Apr-2025	10:17:41 AM	35	1278.00	XCSE
GENMAB A/S	16-Apr-2025	10:17:41 AM	45	1278.00	XCSE
GENMAB A/S	16-Apr-2025	10:17:41 AM	26	1279.00	TQEX
GENMAB A/S	16-Apr-2025	10:17:41 AM	27	1278.00	TQEX
GENMAB A/S	16-Apr-2025	10:17:41 AM	87	1278.00	CEUX
GENMAB A/S	16-Apr-2025	10:17:41 AM	36	1278.00	CEUX
GENMAB A/S	16-Apr-2025	10:17:41 AM	34	1279.00	AQEU
GENMAB A/S	16-Apr-2025	10:17:41 AM	27	1278.00	AQEU
GENMAB A/S	16-Apr-2025	10:18:26 AM	90	1278.00	XCSE
GENMAB A/S	16-Apr-2025	10:18:26 AM	93	1278.00	CEUX
GENMAB A/S	16-Apr-2025	10:18:26 AM	26	1278.00	AQEU
GENMAB A/S	16-Apr-2025	10:18:27 AM	47	1278.00	XCSE
GENMAB A/S	16-Apr-2025	10:18:27 AM	18	1278.00	CEUX
GENMAB A/S	16-Apr-2025	10:18:27 AM	8	1278.00	CEUX
GENMAB A/S	16-Apr-2025	10:18:29 AM	100	1278.50	XCSE
GENMAB A/S	16-Apr-2025	10:18:29 AM	100	1278.50	XCSE
GENMAB A/S	16-Apr-2025	10:18:30 AM	100	1278.50	XCSE
GENMAB A/S	16-Apr-2025	10:18:30 AM	47	1278.50	XCSE

150

Exhibit 99.1(a)

APPENDIX Share buy-back programme - Specification for April 14 – April 18, 2025

GENMAB A/S	16-Apr-2025	10:20:25 AM	12	1279.00	XCSE
GENMAB A/S	16-Apr-2025	10:20:25 AM	45	1279.00	XCSE
GENMAB A/S	16-Apr-2025	10:20:25 AM	11	1279.00	XCSE
GENMAB A/S	16-Apr-2025	10:20:25 AM	12	1279.00	XCSE
GENMAB A/S	16-Apr-2025	10:20:25 AM	37	1279.00	XCSE
GENMAB A/S	16-Apr-2025	10:20:25 AM	89	1278.00	CEUX
GENMAB A/S	16-Apr-2025	10:20:25 AM	33	1278.50	CEUX
GENMAB A/S	16-Apr-2025	10:20:25 AM	56	1278.50	CEUX
GENMAB A/S	16-Apr-2025	10:20:25 AM	30	1279.00	CEUX
GENMAB A/S	16-Apr-2025	10:20:25 AM	8	1279.00	CEUX
GENMAB A/S	16-Apr-2025	10:20:26 AM	63	1279.00	XCSE
GENMAB A/S	16-Apr-2025	10:20:26 AM	11	1279.00	XCSE
GENMAB A/S	16-Apr-2025	10:20:26 AM	43	1279.00	XCSE
GENMAB A/S	16-Apr-2025	10:20:26 AM	2	1279.00	XCSE
GENMAB A/S	16-Apr-2025	10:20:26 AM	11	1279.00	XCSE
GENMAB A/S	16-Apr-2025	10:20:26 AM	11	1279.00	XCSE
GENMAB A/S	16-Apr-2025	10:20:26 AM	13	1279.00	XCSE
GENMAB A/S	16-Apr-2025	10:20:26 AM	80	1279.00	XCSE
GENMAB A/S	16-Apr-2025	10:20:33 AM	3	1278.50	XCSE
GENMAB A/S	16-Apr-2025	10:21:57 AM	30	1279.00	XCSE
GENMAB A/S	16-Apr-2025	10:21:57 AM	87	1279.00	XCSE
GENMAB A/S	16-Apr-2025	10:21:58 AM	13	1279.00	XCSE
GENMAB A/S	16-Apr-2025	10:21:58 AM	100	1279.00	XCSE
GENMAB A/S	16-Apr-2025	10:21:58 AM	21	1279.00	XCSE
GENMAB A/S	16-Apr-2025	10:21:58 AM	31	1279.00	XCSE
GENMAB A/S	16-Apr-2025	10:21:58 AM	36	1279.00	XCSE
GENMAB A/S	16-Apr-2025	10:22:47 AM	87	1279.00	XCSE
GENMAB A/S	16-Apr-2025	10:22:47 AM	51	1279.00	AQEU
GENMAB A/S	16-Apr-2025	10:22:48 AM	32	1279.00	CEUX
GENMAB A/S	16-Apr-2025	10:24:16 AM	14	1281.00	CEUX
GENMAB A/S	16-Apr-2025	10:24:17 AM	36	1281.00	CEUX
GENMAB A/S	16-Apr-2025	10:24:21 AM	32	1281.00	CEUX
GENMAB A/S	16-Apr-2025	10:25:15 AM	91	1280.50	XCSE
GENMAB A/S	16-Apr-2025	10:25:15 AM	45	1281.00	XCSE
GENMAB A/S	16-Apr-2025	10:25:15 AM	19	1281.00	XCSE
GENMAB A/S	16-Apr-2025	10:25:15 AM	88	1280.50	CEUX
GENMAB A/S	16-Apr-2025	10:27:30 AM	93	1282.50	XCSE
GENMAB A/S	16-Apr-2025	10:27:31 AM	18	1283.50	CEUX
GENMAB A/S	16-Apr-2025	10:27:32 AM	37	1284.00	XCSE
GENMAB A/S	16-Apr-2025	10:27:32 AM	54	1284.00	XCSE
GENMAB A/S	16-Apr-2025	10:27:34 AM	35	1284.50	XCSE
GENMAB A/S	16-Apr-2025	10:27:34 AM	23	1284.50	XCSE
GENMAB A/S	16-Apr-2025	10:27:34 AM	25	1284.50	CEUX

151

Exhibit 99.1(a)

APPENDIX Share buy-back programme - Specification for April 14 – April 18, 2025

GENMAB A/S	16-Apr-2025	10:27:35 AM	66	1284.50	CEUX
GENMAB A/S	16-Apr-2025	10:27:35 AM	2	1284.50	CEUX
GENMAB A/S	16-Apr-2025	10:27:39 AM	35	1285.00	XCSE
GENMAB A/S	16-Apr-2025	10:27:39 AM	23	1285.00	XCSE
GENMAB A/S	16-Apr-2025	10:28:00 AM	86	1289.00	XCSE
GENMAB A/S	16-Apr-2025	10:28:00 AM	35	1289.00	XCSE
GENMAB A/S	16-Apr-2025	10:28:00 AM	45	1289.00	XCSE
GENMAB A/S	16-Apr-2025	10:28:00 AM	24	1289.00	XCSE
GENMAB A/S	16-Apr-2025	10:28:00 AM	13	1289.00	XCSE
GENMAB A/S	16-Apr-2025	10:28:01 AM	35	1289.00	XCSE
GENMAB A/S	16-Apr-2025	10:28:01 AM	45	1289.00	XCSE
GENMAB A/S	16-Apr-2025	10:28:01 AM	18	1289.00	XCSE
GENMAB A/S	16-Apr-2025	10:28:01 AM	19	1289.00	XCSE
GENMAB A/S	16-Apr-2025	10:28:01 AM	91	1288.00	XCSE
GENMAB A/S	16-Apr-2025	10:28:01 AM	45	1288.50	XCSE
GENMAB A/S	16-Apr-2025	10:28:01 AM	56	1288.50	XCSE
GENMAB A/S	16-Apr-2025	10:28:01 AM	15	1288.50	XCSE
GENMAB A/S	16-Apr-2025	10:28:01 AM	1	1288.50	XCSE
GENMAB A/S	16-Apr-2025	10:28:01 AM	91	1288.00	CEUX
GENMAB A/S	16-Apr-2025	10:28:01 AM	50	1288.00	AQEU
GENMAB A/S	16-Apr-2025	10:28:02 AM	45	1288.00	XCSE
GENMAB A/S	16-Apr-2025	10:28:02 AM	24	1288.00	XCSE
GENMAB A/S	16-Apr-2025	10:28:02 AM	13	1288.00	XCSE
GENMAB A/S	16-Apr-2025	10:28:08 AM	91	1288.00	XCSE
GENMAB A/S	16-Apr-2025	10:28:10 AM	92	1287.50	CEUX
GENMAB A/S	16-Apr-2025	10:28:14 AM	90	1287.50	XCSE
GENMAB A/S	16-Apr-2025	10:28:17 AM	30	1286.50	CEUX
GENMAB A/S	16-Apr-2025	10:28:18 AM	86	1286.50	XCSE
GENMAB A/S	16-Apr-2025	10:28:18 AM	42	1286.50	TQEX
GENMAB A/S	16-Apr-2025	10:28:18 AM	24	1286.50	CEUX
GENMAB A/S	16-Apr-2025	10:28:18 AM	36	1286.50	CEUX
GENMAB A/S	16-Apr-2025	10:28:54 AM	14	1289.00	XCSE
GENMAB A/S	16-Apr-2025	10:28:55 AM	36	1289.00	XCSE
GENMAB A/S	16-Apr-2025	10:28:56 AM	37	1289.00	XCSE
GENMAB A/S	16-Apr-2025	10:29:04 AM	87	1290.50	XCSE
GENMAB A/S	16-Apr-2025	10:29:11 AM	67	1291.50	CEUX
GENMAB A/S	16-Apr-2025	10:29:18 AM	75	1292.00	XCSE
GENMAB A/S	16-Apr-2025	10:29:18 AM	44	1292.00	AQEU
GENMAB A/S	16-Apr-2025	10:29:20 AM	31	1292.00	TQEX
GENMAB A/S	16-Apr-2025	10:29:23 AM	8	1291.00	XCSE
GENMAB A/S	16-Apr-2025	10:29:23 AM	25	1291.00	XCSE
GENMAB A/S	16-Apr-2025	10:29:23 AM	27	1291.00	TQEX
GENMAB A/S	16-Apr-2025	10:29:23 AM	21	1291.50	CEUX

152

Exhibit 99.1(a)

APPENDIX Share buy-back programme - Specification for April 14 – April 18, 2025

GENMAB A/S	16-Apr-2025	10:29:23 AM	25	1290.50	CEUX
GENMAB A/S	16-Apr-2025	10:29:23 AM	44	1291.00	AQEU
GENMAB A/S	16-Apr-2025	10:29:24 AM	62	1290.50	CEUX
GENMAB A/S	16-Apr-2025	10:29:30 AM	87	1289.50	XCSE
GENMAB A/S	16-Apr-2025	10:29:30 AM	42	1289.50	CEUX
GENMAB A/S	16-Apr-2025	10:29:30 AM	47	1289.50	CEUX
GENMAB A/S	16-Apr-2025	10:29:53 AM	26	1286.50	XCSE
GENMAB A/S	16-Apr-2025	10:30:20 AM	29	1288.50	XCSE
GENMAB A/S	16-Apr-2025	10:30:55 AM	34	1288.00	CEUX
GENMAB A/S	16-Apr-2025	10:31:06 AM	30	1287.50	XCSE
GENMAB A/S	16-Apr-2025	10:31:06 AM	29	1287.00	CEUX
GENMAB A/S	16-Apr-2025	10:31:25 AM	26	1286.50	XCSE
GENMAB A/S	16-Apr-2025	10:31:25 AM	28	1286.50	TQEX
GENMAB A/S	16-Apr-2025	10:31:28 AM	30	1286.00	CEUX
GENMAB A/S	16-Apr-2025	10:31:29 AM	19	1285.00	XCSE
GENMAB A/S	16-Apr-2025	10:31:29 AM	11	1285.00	XCSE
GENMAB A/S	16-Apr-2025	10:33:56 AM	28	1284.00	XCSE
GENMAB A/S	16-Apr-2025	10:33:56 AM	21	1283.50	CEUX
GENMAB A/S	16-Apr-2025	10:33:59 AM	7	1283.50	CEUX
GENMAB A/S	16-Apr-2025	10:34:23 AM	88	1283.50	XCSE
GENMAB A/S	16-Apr-2025	10:34:40 AM	30	1283.00	TQEX
GENMAB A/S	16-Apr-2025	10:34:40 AM	35	1283.00	AQEU
GENMAB A/S	16-Apr-2025	10:35:34 AM	31	1282.50	XCSE
GENMAB A/S	16-Apr-2025	10:35:34 AM	22	1282.50	CEUX
GENMAB A/S	16-Apr-2025	10:35:34 AM	6	1282.50	CEUX
GENMAB A/S	16-Apr-2025	10:35:43 AM	26	1281.50	CEUX
GENMAB A/S	16-Apr-2025	10:35:49 AM	3	1281.50	CEUX
GENMAB A/S	16-Apr-2025	10:36:57 AM	32	1281.50	AQEU
GENMAB A/S	16-Apr-2025	10:37:31 AM	1	1281.00	XCSE
GENMAB A/S	16-Apr-2025	10:37:31 AM	56	1281.00	XCSE
GENMAB A/S	16-Apr-2025	10:38:00 AM	52	1280.50	XCSE
GENMAB A/S	16-Apr-2025	10:38:27 AM	41	1280.50	XCSE
GENMAB A/S	16-Apr-2025	10:41:18 AM	11	1285.00	XCSE
GENMAB A/S	16-Apr-2025	10:42:13 AM	86	1285.00	CEUX
GENMAB A/S	16-Apr-2025	10:42:13 AM	26	1285.00	AQEU
GENMAB A/S	16-Apr-2025	10:44:00 AM	27	1285.00	XCSE
GENMAB A/S	16-Apr-2025	10:44:00 AM	91	1285.00	CEUX
GENMAB A/S	16-Apr-2025	10:44:01 AM	12	1285.00	XCSE
GENMAB A/S	16-Apr-2025	10:44:01 AM	14	1285.00	XCSE
GENMAB A/S	16-Apr-2025	10:44:07 AM	35	1285.00	XCSE
GENMAB A/S	16-Apr-2025	10:44:07 AM	17	1285.00	XCSE
GENMAB A/S	16-Apr-2025	10:44:07 AM	39	1285.00	XCSE
GENMAB A/S	16-Apr-2025	10:45:05 AM	39	1285.00	XCSE

153

Exhibit 99.1(a)

APPENDIX Share buy-back programme - Specification for April 14 – April 18, 2025

GENMAB A/S	16-Apr-2025	10:45:05 AM	28	1285.00	XCSE
GENMAB A/S	16-Apr-2025	10:45:05 AM	37	1285.00	XCSE
GENMAB A/S	16-Apr-2025	10:47:40 AM	91	1284.50	XCSE
GENMAB A/S	16-Apr-2025	10:47:40 AM	27	1284.50	XCSE
GENMAB A/S	16-Apr-2025	10:47:40 AM	35	1284.50	XCSE
GENMAB A/S	16-Apr-2025	10:47:40 AM	39	1284.50	XCSE
GENMAB A/S	16-Apr-2025	10:47:40 AM	16	1284.50	XCSE
GENMAB A/S	16-Apr-2025	10:47:40 AM	74	1284.50	XCSE
GENMAB A/S	16-Apr-2025	10:47:40 AM	37	1284.50	XCSE
GENMAB A/S	16-Apr-2025	10:47:40 AM	5	1284.50	XCSE
GENMAB A/S	16-Apr-2025	10:47:40 AM	1	1284.50	XCSE
GENMAB A/S	16-Apr-2025	10:47:40 AM	27	1284.00	TQEX
GENMAB A/S	16-Apr-2025	10:47:40 AM	87	1284.00	CEUX
GENMAB A/S	16-Apr-2025	10:47:40 AM	4	1284.00	CEUX
GENMAB A/S	16-Apr-2025	10:47:40 AM	28	1284.00	AQEU
GENMAB A/S	16-Apr-2025	10:47:56 AM	70	1284.00	XCSE
GENMAB A/S	16-Apr-2025	10:51:09 AM	26	1284.50	XCSE
GENMAB A/S	16-Apr-2025	10:51:09 AM	39	1284.50	XCSE
GENMAB A/S	16-Apr-2025	10:51:09 AM	14	1284.50	XCSE
GENMAB A/S	16-Apr-2025	10:51:12 AM	14	1284.50	XCSE
GENMAB A/S	16-Apr-2025	10:51:12 AM	11	1284.50	XCSE
GENMAB A/S	16-Apr-2025	10:51:15 AM	37	1284.50	XCSE
GENMAB A/S	16-Apr-2025	10:51:15 AM	39	1284.50	XCSE
GENMAB A/S	16-Apr-2025	10:51:25 AM	39	1284.50	XCSE
GENMAB A/S	16-Apr-2025	10:51:25 AM	37	1284.50	XCSE
GENMAB A/S	16-Apr-2025	10:51:46 AM	13	1284.50	XCSE
GENMAB A/S	16-Apr-2025	10:51:46 AM	2	1284.50	XCSE
GENMAB A/S	16-Apr-2025	10:51:56 AM	13	1284.50	XCSE
GENMAB A/S	16-Apr-2025	10:52:06 AM	39	1284.50	XCSE
GENMAB A/S	16-Apr-2025	10:52:06 AM	21	1284.50	XCSE
GENMAB A/S	16-Apr-2025	10:52:28 AM	38	1284.00	TQEX
GENMAB A/S	16-Apr-2025	10:52:28 AM	36	1284.00	CEUX
GENMAB A/S	16-Apr-2025	10:52:28 AM	29	1284.00	AQEU
GENMAB A/S	16-Apr-2025	10:52:39 AM	91	1283.50	XCSE
GENMAB A/S	16-Apr-2025	10:52:39 AM	36	1283.50	CEUX
GENMAB A/S	16-Apr-2025	10:53:51 AM	15	1283.50	CEUX
GENMAB A/S	16-Apr-2025	10:53:51 AM	36	1284.00	CEUX
GENMAB A/S	16-Apr-2025	10:53:53 AM	92	1282.50	XCSE
GENMAB A/S	16-Apr-2025	10:53:53 AM	26	1283.00	TQEX
GENMAB A/S	16-Apr-2025	10:53:53 AM	93	1283.00	CEUX
GENMAB A/S	16-Apr-2025	10:53:53 AM	26	1283.00	AQEU
GENMAB A/S	16-Apr-2025	10:54:25 AM	26	1282.00	TQEX
GENMAB A/S	16-Apr-2025	10:54:25 AM	78	1281.50	CEUX

154

Exhibit 99.1(a)

APPENDIX Share buy-back programme - Specification for April 14 – April 18, 2025

GENMAB A/S	16-Apr-2025	10:57:15 AM	9	1281.50	CEUX
GENMAB A/S	16-Apr-2025	10:57:50 AM	89	1283.00	XCSE
GENMAB A/S	16-Apr-2025	10:57:50 AM	39	1283.50	XCSE
GENMAB A/S	16-Apr-2025	10:57:50 AM	14	1283.50	XCSE
GENMAB A/S	16-Apr-2025	10:57:50 AM	13	1283.50	XCSE
GENMAB A/S	16-Apr-2025	10:57:50 AM	14	1283.50	XCSE
GENMAB A/S	16-Apr-2025	10:58:08 AM	4	1282.50	CEUX
GENMAB A/S	16-Apr-2025	10:59:02 AM	32	1282.50	CEUX
GENMAB A/S	16-Apr-2025	10:59:10 AM	26	1282.50	AQEU
GENMAB A/S	16-Apr-2025	10:59:10 AM	28	1282.50	TQEX
GENMAB A/S	16-Apr-2025	10:59:10 AM	51	1282.50	CEUX
GENMAB A/S	16-Apr-2025	11:00:55 AM	13	1282.00	XCSE
GENMAB A/S	16-Apr-2025	11:00:55 AM	13	1282.00	XCSE
GENMAB A/S	16-Apr-2025	11:00:55 AM	2	1281.50	TQEX
GENMAB A/S	16-Apr-2025	11:01:15 AM	89	1281.50	XCSE
GENMAB A/S	16-Apr-2025	11:01:15 AM	29	1281.50	TQEX
GENMAB A/S	16-Apr-2025	11:01:15 AM	88	1281.00	CEUX
GENMAB A/S	16-Apr-2025	11:01:21 AM	27	1281.50	AQEU
GENMAB A/S	16-Apr-2025	11:04:05 AM	88	1281.50	XCSE
GENMAB A/S	16-Apr-2025	11:04:05 AM	89	1281.50	CEUX
GENMAB A/S	16-Apr-2025	11:05:01 AM	25	1282.50	CEUX
GENMAB A/S	16-Apr-2025	11:05:01 AM	3	1282.50	CEUX
GENMAB A/S	16-Apr-2025	11:05:01 AM	12	1282.50	CEUX
GENMAB A/S	16-Apr-2025	11:05:30 AM	11	1282.50	XCSE
GENMAB A/S	16-Apr-2025	11:05:30 AM	40	1283.00	XCSE
GENMAB A/S	16-Apr-2025	11:05:30 AM	39	1283.00	XCSE
GENMAB A/S	16-Apr-2025	11:05:30 AM	27	1283.00	XCSE
GENMAB A/S	16-Apr-2025	11:05:35 AM	92	1282.00	CEUX
GENMAB A/S	16-Apr-2025	11:08:05 AM	13	1281.50	TQEX
GENMAB A/S	16-Apr-2025	11:08:05 AM	16	1281.50	TQEX
GENMAB A/S	16-Apr-2025	11:08:05 AM	74	1281.00	CEUX
GENMAB A/S	16-Apr-2025	11:11:29 AM	34	1283.50	TQEX
GENMAB A/S	16-Apr-2025	11:11:29 AM	1	1283.50	CEUX
GENMAB A/S	16-Apr-2025	11:11:29 AM	89	1283.50	CEUX
GENMAB A/S	16-Apr-2025	11:11:41 AM	1	1283.00	XCSE
GENMAB A/S	16-Apr-2025	11:11:51 AM	12	1283.50	CEUX
GENMAB A/S	16-Apr-2025	11:11:51 AM	14	1283.50	CEUX
GENMAB A/S	16-Apr-2025	11:11:52 AM	14	1283.50	XCSE
GENMAB A/S	16-Apr-2025	11:11:53 AM	13	1283.50	XCSE
GENMAB A/S	16-Apr-2025	11:11:54 AM	14	1283.50	XCSE
GENMAB A/S	16-Apr-2025	11:11:55 AM	12	1283.50	XCSE
GENMAB A/S	16-Apr-2025	11:11:56 AM	14	1283.50	XCSE
GENMAB A/S	16-Apr-2025	11:13:15 AM	88	1283.00	XCSE

155

Exhibit 99.1(a)

APPENDIX Share buy-back programme - Specification for April 14 – April 18, 2025

GENMAB A/S	16-Apr-2025	11:13:15 AM	40	1283.00	XCSE
GENMAB A/S	16-Apr-2025	11:13:15 AM	39	1283.00	XCSE
GENMAB A/S	16-Apr-2025	11:13:15 AM	38	1283.00	XCSE
GENMAB A/S	16-Apr-2025	11:13:15 AM	35	1283.00	AQEU
GENMAB A/S	16-Apr-2025	11:13:15 AM	33	1282.50	CEUX
GENMAB A/S	16-Apr-2025	11:13:15 AM	7	1283.00	CEUX
GENMAB A/S	16-Apr-2025	11:13:21 AM	9	1283.00	CEUX
GENMAB A/S	16-Apr-2025	11:13:21 AM	3	1283.00	CEUX
GENMAB A/S	16-Apr-2025	11:13:22 AM	12	1283.50	XCSE
GENMAB A/S	16-Apr-2025	11:13:38 AM	15	1283.50	XCSE
GENMAB A/S	16-Apr-2025	11:13:38 AM	11	1283.50	XCSE
GENMAB A/S	16-Apr-2025	11:16:22 AM	45	1283.50	XCSE
GENMAB A/S	16-Apr-2025	11:16:22 AM	36	1283.50	CEUX
GENMAB A/S	16-Apr-2025	11:17:15 AM	91	1283.00	XCSE
GENMAB A/S	16-Apr-2025	11:17:15 AM	26	1283.00	AQEU
GENMAB A/S	16-Apr-2025	11:17:15 AM	36	1282.50	TQEX
GENMAB A/S	16-Apr-2025	11:17:15 AM	60	1282.50	CEUX
GENMAB A/S	16-Apr-2025	11:17:15 AM	36	1282.50	CEUX
GENMAB A/S	16-Apr-2025	11:17:15 AM	7	1282.50	CEUX
GENMAB A/S	16-Apr-2025	11:17:15 AM	7	1282.50	CEUX
GENMAB A/S	16-Apr-2025	11:17:15 AM	7	1282.50	CEUX
GENMAB A/S	16-Apr-2025	11:17:15 AM	7	1282.50	CEUX
GENMAB A/S	16-Apr-2025	11:17:15 AM	12	1282.50	CEUX
GENMAB A/S	16-Apr-2025	11:17:17 AM	88	1282.00	XCSE
GENMAB A/S	16-Apr-2025	11:17:17 AM	36	1282.00	AQEU
GENMAB A/S	16-Apr-2025	11:19:05 AM	26	1281.50	TQEX
GENMAB A/S	16-Apr-2025	11:19:05 AM	12	1281.00	CEUX
GENMAB A/S	16-Apr-2025	11:19:36 AM	88	1281.00	XCSE
GENMAB A/S	16-Apr-2025	11:19:36 AM	26	1281.00	AQEU
GENMAB A/S	16-Apr-2025	11:19:36 AM	15	1281.00	CEUX
GENMAB A/S	16-Apr-2025	11:19:36 AM	7	1281.00	CEUX
GENMAB A/S	16-Apr-2025	11:19:37 AM	6	1281.00	CEUX
GENMAB A/S	16-Apr-2025	11:20:17 AM	9	1281.00	CEUX
GENMAB A/S	16-Apr-2025	11:20:17 AM	18	1281.00	CEUX
GENMAB A/S	16-Apr-2025	11:20:17 AM	7	1281.00	CEUX
GENMAB A/S	16-Apr-2025	11:20:18 AM	6	1280.50	CEUX
GENMAB A/S	16-Apr-2025	11:20:18 AM	6	1280.50	CEUX
GENMAB A/S	16-Apr-2025	11:20:18 AM	7	1280.50	CEUX
GENMAB A/S	16-Apr-2025	11:21:05 AM	89	1279.50	XCSE
GENMAB A/S	16-Apr-2025	11:21:05 AM	30	1280.00	AQEU
GENMAB A/S	16-Apr-2025	11:21:05 AM	32	1280.00	TQEX
GENMAB A/S	16-Apr-2025	11:21:05 AM	90	1279.50	CEUX
GENMAB A/S	16-Apr-2025	11:23:15 AM	26	1279.00	TQEX

156

Exhibit 99.1(a)

APPENDIX Share buy-back programme - Specification for April 14 – April 18, 2025

GENMAB A/S	16-Apr-2025	11:23:55 AM	75	1278.00	CEUX
GENMAB A/S	16-Apr-2025	11:24:11 AM	10	1278.50	CEUX
GENMAB A/S	16-Apr-2025	11:25:43 AM	92	1278.00	XCSE
GENMAB A/S	16-Apr-2025	11:25:43 AM	29	1278.00	TQEX
GENMAB A/S	16-Apr-2025	11:25:43 AM	36	1278.50	CEUX
GENMAB A/S	16-Apr-2025	11:25:43 AM	17	1278.00	CEUX
GENMAB A/S	16-Apr-2025	11:25:44 AM	13	1279.00	XCSE
GENMAB A/S	16-Apr-2025	11:25:44 AM	27	1279.00	XCSE
GENMAB A/S	16-Apr-2025	11:25:44 AM	12	1279.00	XCSE
GENMAB A/S	16-Apr-2025	11:25:45 AM	12	1279.00	XCSE
GENMAB A/S	16-Apr-2025	11:26:07 AM	93	1280.00	CEUX
GENMAB A/S	16-Apr-2025	11:29:12 AM	86	1280.00	XCSE
GENMAB A/S	16-Apr-2025	11:30:13 AM	90	1279.00	XCSE
GENMAB A/S	16-Apr-2025	11:30:13 AM	35	1279.00	XCSE
GENMAB A/S	16-Apr-2025	11:30:13 AM	27	1278.50	AQEU
GENMAB A/S	16-Apr-2025	11:30:13 AM	27	1278.50	TQEX
GENMAB A/S	16-Apr-2025	11:30:13 AM	57	1279.00	CEUX
GENMAB A/S	16-Apr-2025	11:30:13 AM	35	1279.00	CEUX
GENMAB A/S	16-Apr-2025	11:31:05 AM	62	1278.00	CEUX
GENMAB A/S	16-Apr-2025	11:32:05 AM	91	1278.00	XCSE
GENMAB A/S	16-Apr-2025	11:32:05 AM	25	1278.00	CEUX
GENMAB A/S	16-Apr-2025	11:32:53 AM	93	1278.00	XCSE
GENMAB A/S	16-Apr-2025	11:32:53 AM	27	1278.00	TQEX
GENMAB A/S	16-Apr-2025	11:32:53 AM	91	1278.00	CEUX
GENMAB A/S	16-Apr-2025	11:36:03 AM	26	1279.00	XCSE
GENMAB A/S	16-Apr-2025	11:36:03 AM	36	1279.00	CEUX
GENMAB A/S	16-Apr-2025	11:37:35 AM	64	1278.50	CEUX
GENMAB A/S	16-Apr-2025	11:39:15 AM	92	1279.50	XCSE
GENMAB A/S	16-Apr-2025	11:39:27 AM	27	1279.50	XCSE
GENMAB A/S	16-Apr-2025	11:41:15 AM	25	1278.50	CEUX
GENMAB A/S	16-Apr-2025	11:41:42 AM	27	1279.00	TQEX
GENMAB A/S	16-Apr-2025	11:42:55 AM	87	1278.50	XCSE
GENMAB A/S	16-Apr-2025	11:42:55 AM	27	1278.00	TQEX
GENMAB A/S	16-Apr-2025	11:42:55 AM	26	1278.50	AQEU
GENMAB A/S	16-Apr-2025	11:42:55 AM	7	1278.50	AQEU
GENMAB A/S	16-Apr-2025	11:43:55 AM	88	1277.50	CEUX
GENMAB A/S	16-Apr-2025	11:46:42 AM	21	1279.00	XCSE
GENMAB A/S	16-Apr-2025	11:46:42 AM	39	1279.00	XCSE
GENMAB A/S	16-Apr-2025	11:46:52 AM	14	1279.00	XCSE
GENMAB A/S	16-Apr-2025	11:46:52 AM	12	1279.00	XCSE
GENMAB A/S	16-Apr-2025	11:47:15 AM	92	1278.50	XCSE
GENMAB A/S	16-Apr-2025	11:48:45 AM	66	1278.00	CEUX
GENMAB A/S	16-Apr-2025	11:49:55 AM	25	1278.00	CEUX

157

Exhibit 99.1(a)

APPENDIX Share buy-back programme - Specification for April 14 – April 18, 2025

GENMAB A/S	16-Apr-2025	11:55:00 AM	9	1279.00	CEUX
GENMAB A/S	16-Apr-2025	11:55:01 AM	36	1279.00	CEUX
GENMAB A/S	16-Apr-2025	11:55:02 AM	36	1279.00	CEUX
GENMAB A/S	16-Apr-2025	11:55:06 AM	14	1279.00	CEUX
GENMAB A/S	16-Apr-2025	11:56:35 AM	35	1279.00	TQEX
GENMAB A/S	16-Apr-2025	11:56:35 AM	90	1279.00	CEUX
GENMAB A/S	16-Apr-2025	11:56:45 AM	12	1279.00	TQEX
GENMAB A/S	16-Apr-2025	11:56:45 AM	36	1279.00	CEUX
GENMAB A/S	16-Apr-2025	11:56:53 AM	13	1279.00	CEUX
GENMAB A/S	16-Apr-2025	11:57:56 AM	67	1278.50	XCSE
GENMAB A/S	16-Apr-2025	11:59:25 AM	26	1278.50	XCSE
GENMAB A/S	16-Apr-2025	11:59:25 AM	26	1278.00	TQEX
GENMAB A/S	16-Apr-2025	11:59:25 AM	74	1278.50	AQEU
GENMAB A/S	16-Apr-2025	11:59:25 AM	18	1278.50	CEUX
GENMAB A/S	16-Apr-2025	11:59:25 AM	50	1278.50	CEUX
GENMAB A/S	16-Apr-2025	12:00:19 PM	21	1278.50	CEUX
GENMAB A/S	16-Apr-2025	12:00:19 PM	2	1278.50	CEUX
GENMAB A/S	16-Apr-2025	12:00:19 PM	20	1278.50	CEUX
GENMAB A/S	16-Apr-2025	12:02:19 PM	12	1280.00	CEUX
GENMAB A/S	16-Apr-2025	12:04:35 PM	56	1279.50	CEUX
GENMAB A/S	16-Apr-2025	12:07:15 PM	86	1279.50	XCSE
GENMAB A/S	16-Apr-2025	12:07:15 PM	35	1279.50	CEUX
GENMAB A/S	16-Apr-2025	12:10:25 PM	32	1280.00	XCSE
GENMAB A/S	16-Apr-2025	12:10:25 PM	16	1280.00	XCSE
GENMAB A/S	16-Apr-2025	12:10:25 PM	25	1280.00	XCSE
GENMAB A/S	16-Apr-2025	12:10:25 PM	26	1280.00	XCSE
GENMAB A/S	16-Apr-2025	12:10:25 PM	14	1280.00	XCSE
GENMAB A/S	16-Apr-2025	12:10:29 PM	25	1280.00	XCSE
GENMAB A/S	16-Apr-2025	12:10:29 PM	20	1280.00	XCSE
GENMAB A/S	16-Apr-2025	12:12:15 PM	13	1279.50	XCSE
GENMAB A/S	16-Apr-2025	12:12:15 PM	13	1279.50	XCSE
GENMAB A/S	16-Apr-2025	12:12:15 PM	9	1279.50	XCSE
GENMAB A/S	16-Apr-2025	12:12:15 PM	12	1279.00	TQEX
GENMAB A/S	16-Apr-2025	12:12:15 PM	25	1279.00	TQEX
GENMAB A/S	16-Apr-2025	12:12:15 PM	89	1278.50	CEUX
GENMAB A/S	16-Apr-2025	12:12:26 PM	54	1279.00	AQEU
GENMAB A/S	16-Apr-2025	12:12:26 PM	10	1279.00	CEUX
GENMAB A/S	16-Apr-2025	12:14:57 PM	11	1278.50	XCSE
GENMAB A/S	16-Apr-2025	12:15:09 PM	81	1278.50	XCSE
GENMAB A/S	16-Apr-2025	12:15:09 PM	26	1278.50	XCSE
GENMAB A/S	16-Apr-2025	12:15:09 PM	20	1278.50	CEUX
GENMAB A/S	16-Apr-2025	12:15:43 PM	9	1278.50	XCSE
GENMAB A/S	16-Apr-2025	12:15:43 PM	15	1278.50	XCSE

158

Exhibit 99.1(a)

APPENDIX Share buy-back programme - Specification for April 14 – April 18, 2025

GENMAB A/S	16-Apr-2025	12:15:43 PM	2	1278.50	XCSE
GENMAB A/S	16-Apr-2025	12:15:43 PM	17	1278.00	TQEX
GENMAB A/S	16-Apr-2025	12:15:43 PM	19	1278.00	TQEX
GENMAB A/S	16-Apr-2025	12:15:43 PM	45	1278.50	CEUX
GENMAB A/S	16-Apr-2025	12:15:43 PM	7	1278.50	CEUX
GENMAB A/S	16-Apr-2025	12:17:45 PM	92	1277.50	XCSE
GENMAB A/S	16-Apr-2025	12:17:45 PM	2	1277.50	AQEU
GENMAB A/S	16-Apr-2025	12:17:45 PM	57	1277.50	CEUX
GENMAB A/S	16-Apr-2025	12:17:45 PM	2	1277.50	CEUX
GENMAB A/S	16-Apr-2025	12:18:27 PM	29	1277.50	CEUX
GENMAB A/S	16-Apr-2025	12:19:00 PM	86	1279.50	XCSE
GENMAB A/S	16-Apr-2025	12:19:00 PM	47	1279.50	XCSE
GENMAB A/S	16-Apr-2025	12:19:07 PM	100	1279.50	XCSE
GENMAB A/S	16-Apr-2025	12:19:13 PM	90	1279.50	XCSE
GENMAB A/S	16-Apr-2025	12:20:22 PM	53	1279.00	TQEX
GENMAB A/S	16-Apr-2025	12:20:22 PM	36	1279.50	CEUX
GENMAB A/S	16-Apr-2025	12:20:22 PM	33	1279.00	CEUX
GENMAB A/S	16-Apr-2025	12:20:22 PM	54	1279.00	CEUX
GENMAB A/S	16-Apr-2025	12:20:22 PM	10	1279.00	CEUX
GENMAB A/S	16-Apr-2025	12:22:45 PM	89	1278.50	XCSE
GENMAB A/S	16-Apr-2025	12:22:45 PM	71	1278.50	AQEU
GENMAB A/S	16-Apr-2025	12:22:45 PM	69	1278.00	CEUX
GENMAB A/S	16-Apr-2025	12:24:43 PM	19	1278.50	CEUX
GENMAB A/S	16-Apr-2025	12:25:45 PM	21	1278.00	CEUX
GENMAB A/S	16-Apr-2025	12:27:29 PM	58	1278.00	TQEX
GENMAB A/S	16-Apr-2025	12:27:29 PM	10	1278.00	CEUX
GENMAB A/S	16-Apr-2025	12:27:30 PM	15	1278.00	CEUX
GENMAB A/S	16-Apr-2025	12:27:32 PM	2	1278.00	CEUX
GENMAB A/S	16-Apr-2025	12:27:59 PM	17	1278.00	XCSE
GENMAB A/S	16-Apr-2025	12:27:59 PM	74	1278.00	XCSE
GENMAB A/S	16-Apr-2025	12:29:25 PM	87	1278.00	XCSE
GENMAB A/S	16-Apr-2025	12:29:25 PM	34	1278.00	TQEX
GENMAB A/S	16-Apr-2025	12:29:25 PM	91	1278.00	CEUX
GENMAB A/S	16-Apr-2025	12:30:55 PM	14	1278.00	CEUX
GENMAB A/S	16-Apr-2025	12:34:25 PM	14	1278.50	XCSE
GENMAB A/S	16-Apr-2025	12:34:25 PM	79	1278.00	CEUX
GENMAB A/S	16-Apr-2025	12:35:03 PM	20	1278.50	CEUX
GENMAB A/S	16-Apr-2025	12:35:14 PM	15	1279.00	XCSE
GENMAB A/S	16-Apr-2025	12:35:14 PM	15	1279.00	XCSE
GENMAB A/S	16-Apr-2025	12:35:14 PM	37	1279.00	XCSE
GENMAB A/S	16-Apr-2025	12:35:14 PM	13	1279.00	XCSE
GENMAB A/S	16-Apr-2025	12:35:14 PM	37	1279.00	XCSE
GENMAB A/S	16-Apr-2025	12:35:14 PM	15	1279.00	XCSE

159

Exhibit 99.1(a)

APPENDIX Share buy-back programme - Specification for April 14 – April 18, 2025

GENMAB A/S	16-Apr-2025	12:35:14 PM	14	1279.00	XCSE
GENMAB A/S	16-Apr-2025	12:35:14 PM	16	1279.00	XCSE
GENMAB A/S	16-Apr-2025	12:35:14 PM	37	1279.00	XCSE
GENMAB A/S	16-Apr-2025	12:35:14 PM	12	1279.00	XCSE
GENMAB A/S	16-Apr-2025	12:37:01 PM	13	1278.00	XCSE
GENMAB A/S	16-Apr-2025	12:37:01 PM	80	1278.00	XCSE
GENMAB A/S	16-Apr-2025	12:37:01 PM	31	1278.00	TQEX
GENMAB A/S	16-Apr-2025	12:37:01 PM	26	1277.50	AQEU
GENMAB A/S	16-Apr-2025	12:37:01 PM	8	1278.00	CEUX
GENMAB A/S	16-Apr-2025	12:37:01 PM	68	1277.00	CEUX
GENMAB A/S	16-Apr-2025	12:39:15 PM	89	1277.00	XCSE
GENMAB A/S	16-Apr-2025	12:39:15 PM	10	1277.00	TQEX
GENMAB A/S	16-Apr-2025	12:39:15 PM	10	1277.00	TQEX
GENMAB A/S	16-Apr-2025	12:39:15 PM	7	1277.00	TQEX
GENMAB A/S	16-Apr-2025	12:39:15 PM	25	1277.00	CEUX
GENMAB A/S	16-Apr-2025	12:42:35 PM	35	1277.00	XCSE
GENMAB A/S	16-Apr-2025	12:42:35 PM	65	1276.00	CEUX
GENMAB A/S	16-Apr-2025	12:43:13 PM	24	1276.50	AQEU
GENMAB A/S	16-Apr-2025	12:43:26 PM	3	1276.50	AQEU
GENMAB A/S	16-Apr-2025	12:45:45 PM	87	1276.00	XCSE
GENMAB A/S	16-Apr-2025	12:45:45 PM	22	1276.00	TQEX
GENMAB A/S	16-Apr-2025	12:45:45 PM	26	1276.00	CEUX
GENMAB A/S	16-Apr-2025	12:47:31 PM	93	1276.50	XCSE
GENMAB A/S	16-Apr-2025	12:47:31 PM	24	1276.50	CEUX
GENMAB A/S	16-Apr-2025	12:47:38 PM	2	1277.00	CEUX
GENMAB A/S	16-Apr-2025	12:47:38 PM	66	1276.50	CEUX
GENMAB A/S	16-Apr-2025	12:47:42 PM	36	1277.50	CEUX
GENMAB A/S	16-Apr-2025	12:53:21 PM	9	1280.00	XCSE
GENMAB A/S	16-Apr-2025	12:53:21 PM	31	1280.00	XCSE
GENMAB A/S	16-Apr-2025	12:53:35 PM	25	1280.00	XCSE
GENMAB A/S	16-Apr-2025	12:53:35 PM	19	1280.00	XCSE
GENMAB A/S	16-Apr-2025	12:53:56 PM	13	1280.00	XCSE
GENMAB A/S	16-Apr-2025	12:54:00 PM	36	1280.00	CEUX
GENMAB A/S	16-Apr-2025	12:54:01 PM	36	1280.00	CEUX
GENMAB A/S	16-Apr-2025	12:54:08 PM	39	1280.00	XCSE
GENMAB A/S	16-Apr-2025	12:54:08 PM	56	1279.50	CEUX
GENMAB A/S	16-Apr-2025	12:54:08 PM	34	1279.50	CEUX
GENMAB A/S	16-Apr-2025	12:54:08 PM	36	1280.00	CEUX
GENMAB A/S	16-Apr-2025	12:54:47 PM	15	1280.00	XCSE
GENMAB A/S	16-Apr-2025	12:54:47 PM	39	1280.00	XCSE
GENMAB A/S	16-Apr-2025	12:54:47 PM	15	1280.00	XCSE
GENMAB A/S	16-Apr-2025	12:54:47 PM	39	1280.00	XCSE
GENMAB A/S	16-Apr-2025	12:54:47 PM	13	1280.00	XCSE

160

Exhibit 99.1(a)

APPENDIX Share buy-back programme - Specification for April 14 – April 18, 2025

GENMAB A/S	16-Apr-2025	12:55:24 PM	39	1280.00	XCSE
GENMAB A/S	16-Apr-2025	12:55:24 PM	39	1280.00	XCSE
GENMAB A/S	16-Apr-2025	12:55:24 PM	2	1280.00	XCSE
GENMAB A/S	16-Apr-2025	12:55:24 PM	17	1279.50	CEUX
GENMAB A/S	16-Apr-2025	12:55:45 PM	63	1279.50	CEUX
GENMAB A/S	16-Apr-2025	12:55:45 PM	7	1279.50	CEUX
GENMAB A/S	16-Apr-2025	12:57:04 PM	31	1279.50	XCSE
GENMAB A/S	16-Apr-2025	12:57:04 PM	36	1279.50	CEUX
GENMAB A/S	16-Apr-2025	12:57:04 PM	17	1279.50	CEUX
GENMAB A/S	16-Apr-2025	12:57:10 PM	36	1279.50	CEUX
GENMAB A/S	16-Apr-2025	12:57:15 PM	2	1279.50	CEUX
GENMAB A/S	16-Apr-2025	12:57:36 PM	86	1279.00	XCSE
GENMAB A/S	16-Apr-2025	12:57:36 PM	44	1279.50	XCSE
GENMAB A/S	16-Apr-2025	12:57:36 PM	36	1279.50	CEUX
GENMAB A/S	16-Apr-2025	12:57:36 PM	49	1279.50	CEUX
GENMAB A/S	16-Apr-2025	12:58:40 PM	49	1278.50	TQEX
GENMAB A/S	16-Apr-2025	12:58:40 PM	87	1278.50	AQEU
GENMAB A/S	16-Apr-2025	12:58:40 PM	93	1278.50	CEUX
GENMAB A/S	16-Apr-2025	12:58:40 PM	36	1278.50	CEUX
GENMAB A/S	16-Apr-2025	1:01:55 PM	65	1278.50	CEUX
GENMAB A/S	16-Apr-2025	1:01:55 PM	24	1278.50	CEUX
GENMAB A/S	16-Apr-2025	1:03:25 PM	86	1278.50	XCSE
GENMAB A/S	16-Apr-2025	1:03:25 PM	48	1278.50	TQEX
GENMAB A/S	16-Apr-2025	1:03:29 PM	2	1278.50	AQEU
GENMAB A/S	16-Apr-2025	1:03:42 PM	73	1278.50	AQEU
GENMAB A/S	16-Apr-2025	1:04:05 PM	15	1278.50	CEUX
GENMAB A/S	16-Apr-2025	1:06:41 PM	31	1280.50	XCSE
GENMAB A/S	16-Apr-2025	1:06:41 PM	29	1280.50	XCSE
GENMAB A/S	16-Apr-2025	1:08:09 PM	39	1281.50	XCSE
GENMAB A/S	16-Apr-2025	1:08:09 PM	25	1281.50	XCSE
GENMAB A/S	16-Apr-2025	1:08:09 PM	27	1281.50	XCSE
GENMAB A/S	16-Apr-2025	1:10:45 PM	48	1281.50	CEUX
GENMAB A/S	16-Apr-2025	1:10:45 PM	43	1281.50	CEUX
GENMAB A/S	16-Apr-2025	1:12:20 PM	31	1281.50	XCSE
GENMAB A/S	16-Apr-2025	1:12:20 PM	36	1281.50	CEUX
GENMAB A/S	16-Apr-2025	1:12:21 PM	7	1281.50	CEUX
GENMAB A/S	16-Apr-2025	1:12:21 PM	51	1281.50	CEUX
GENMAB A/S	16-Apr-2025	1:12:21 PM	17	1281.50	CEUX
GENMAB A/S	16-Apr-2025	1:12:29 PM	31	1281.50	XCSE
GENMAB A/S	16-Apr-2025	1:12:29 PM	2	1281.50	XCSE
GENMAB A/S	16-Apr-2025	1:13:33 PM	36	1281.50	CEUX
GENMAB A/S	16-Apr-2025	1:13:34 PM	31	1281.50	XCSE
GENMAB A/S	16-Apr-2025	1:13:34 PM	50	1281.50	CEUX

161

Exhibit 99.1(a)

APPENDIX Share buy-back programme - Specification for April 14 – April 18, 2025

GENMAB A/S	16-Apr-2025	1:13:41 PM	36	1281.50	CEUX
GENMAB A/S	16-Apr-2025	1:17:25 PM	39	1282.00	XCSE
GENMAB A/S	16-Apr-2025	1:17:25 PM	28	1282.00	XCSE
GENMAB A/S	16-Apr-2025	1:17:25 PM	15	1282.00	XCSE
GENMAB A/S	16-Apr-2025	1:17:25 PM	69	1281.50	CEUX
GENMAB A/S	16-Apr-2025	1:20:34 PM	92	1282.50	CEUX
GENMAB A/S	16-Apr-2025	1:20:34 PM	15	1282.50	CEUX
GENMAB A/S	16-Apr-2025	1:25:05 PM	90	1282.00	XCSE
GENMAB A/S	16-Apr-2025	1:25:05 PM	39	1282.50	XCSE
GENMAB A/S	16-Apr-2025	1:25:05 PM	29	1282.50	XCSE
GENMAB A/S	16-Apr-2025	1:25:05 PM	29	1282.50	XCSE
GENMAB A/S	16-Apr-2025	1:25:05 PM	20	1282.50	XCSE
GENMAB A/S	16-Apr-2025	1:25:05 PM	69	1282.00	TQEX
GENMAB A/S	16-Apr-2025	1:27:42 PM	50	1283.00	XCSE
GENMAB A/S	16-Apr-2025	1:27:42 PM	6	1283.50	CEUX
GENMAB A/S	16-Apr-2025	1:27:42 PM	18	1283.50	CEUX
GENMAB A/S	16-Apr-2025	1:29:02 PM	2	1283.00	AQEU
GENMAB A/S	16-Apr-2025	1:31:05 PM	39	1283.00	XCSE
GENMAB A/S	16-Apr-2025	1:31:05 PM	85	1283.00	AQEU
GENMAB A/S	16-Apr-2025	1:32:21 PM	35	1283.00	XCSE
GENMAB A/S	16-Apr-2025	1:32:21 PM	28	1283.00	XCSE
GENMAB A/S	16-Apr-2025	1:32:21 PM	39	1283.00	XCSE
GENMAB A/S	16-Apr-2025	1:32:21 PM	36	1283.00	CEUX
GENMAB A/S	16-Apr-2025	1:33:00 PM	39	1283.00	XCSE
GENMAB A/S	16-Apr-2025	1:33:00 PM	12	1283.00	XCSE
GENMAB A/S	16-Apr-2025	1:33:00 PM	36	1283.00	CEUX
GENMAB A/S	16-Apr-2025	1:33:00 PM	77	1282.50	CEUX
GENMAB A/S	16-Apr-2025	1:33:01 PM	39	1283.00	XCSE
GENMAB A/S	16-Apr-2025	1:33:05 PM	39	1283.00	XCSE
GENMAB A/S	16-Apr-2025	1:33:05 PM	35	1283.00	XCSE
GENMAB A/S	16-Apr-2025	1:33:05 PM	39	1283.00	XCSE
GENMAB A/S	16-Apr-2025	1:33:05 PM	9	1282.50	CEUX
GENMAB A/S	16-Apr-2025	1:33:09 PM	14	1282.00	AQEU
GENMAB A/S	16-Apr-2025	1:33:11 PM	99	1282.50	CEUX
GENMAB A/S	16-Apr-2025	1:33:21 PM	68	1282.50	CEUX
GENMAB A/S	16-Apr-2025	1:33:43 PM	39	1283.50	XCSE
GENMAB A/S	16-Apr-2025	1:33:43 PM	16	1283.50	XCSE
GENMAB A/S	16-Apr-2025	1:33:43 PM	16	1283.50	XCSE
GENMAB A/S	16-Apr-2025	1:33:44 PM	36	1283.50	CEUX
GENMAB A/S	16-Apr-2025	1:36:06 PM	93	1283.50	XCSE
GENMAB A/S	16-Apr-2025	1:36:06 PM	29	1283.50	XCSE
GENMAB A/S	16-Apr-2025	1:36:06 PM	77	1283.50	TQEX
GENMAB A/S	16-Apr-2025	1:36:06 PM	93	1283.50	CEUX

162

Exhibit 99.1(a)

APPENDIX Share buy-back programme - Specification for April 14 – April 18, 2025

GENMAB A/S	16-Apr-2025	1:36:06 PM	36	1283.50	CEUX
GENMAB A/S	16-Apr-2025	1:36:12 PM	8	1283.50	CEUX
GENMAB A/S	16-Apr-2025	1:38:25 PM	89	1283.50	XCSE
GENMAB A/S	16-Apr-2025	1:38:25 PM	80	1283.50	CEUX
GENMAB A/S	16-Apr-2025	1:38:25 PM	10	1283.50	CEUX
GENMAB A/S	16-Apr-2025	1:38:25 PM	23	1283.50	CEUX
GENMAB A/S	16-Apr-2025	1:38:26 PM	47	1283.50	XCSE
GENMAB A/S	16-Apr-2025	1:42:55 PM	92	1284.00	XCSE
GENMAB A/S	16-Apr-2025	1:45:12 PM	36	1285.00	CEUX
GENMAB A/S	16-Apr-2025	1:45:17 PM	36	1285.00	CEUX
GENMAB A/S	16-Apr-2025	1:45:35 PM	13	1285.00	XCSE
GENMAB A/S	16-Apr-2025	1:45:37 PM	36	1285.00	CEUX
GENMAB A/S	16-Apr-2025	1:45:56 PM	36	1285.00	CEUX
GENMAB A/S	16-Apr-2025	1:46:04 PM	36	1285.00	CEUX
GENMAB A/S	16-Apr-2025	1:46:47 PM	39	1285.00	XCSE
GENMAB A/S	16-Apr-2025	1:46:47 PM	37	1285.00	XCSE
GENMAB A/S	16-Apr-2025	1:46:47 PM	36	1285.00	CEUX
GENMAB A/S	16-Apr-2025	1:47:00 PM	2	1285.00	XCSE
GENMAB A/S	16-Apr-2025	1:47:00 PM	39	1285.00	XCSE
GENMAB A/S	16-Apr-2025	1:47:00 PM	37	1285.00	XCSE
GENMAB A/S	16-Apr-2025	1:47:45 PM	37	1285.00	XCSE
GENMAB A/S	16-Apr-2025	1:47:45 PM	39	1285.00	XCSE
GENMAB A/S	16-Apr-2025	1:47:55 PM	39	1285.00	XCSE
GENMAB A/S	16-Apr-2025	1:47:55 PM	37	1285.00	XCSE
GENMAB A/S	16-Apr-2025	1:47:55 PM	33	1285.00	XCSE
GENMAB A/S	16-Apr-2025	1:48:01 PM	39	1285.00	XCSE
GENMAB A/S	16-Apr-2025	1:48:01 PM	2	1285.00	XCSE
GENMAB A/S	16-Apr-2025	1:48:29 PM	2	1285.00	CEUX
GENMAB A/S	16-Apr-2025	1:48:29 PM	17	1285.00	CEUX
GENMAB A/S	16-Apr-2025	1:48:34 PM	14	1285.00	XCSE
GENMAB A/S	16-Apr-2025	1:48:37 PM	39	1285.00	XCSE
GENMAB A/S	16-Apr-2025	1:48:37 PM	37	1285.00	XCSE
GENMAB A/S	16-Apr-2025	1:48:37 PM	36	1285.00	CEUX
GENMAB A/S	16-Apr-2025	1:49:00 PM	39	1285.00	XCSE
GENMAB A/S	16-Apr-2025	1:49:00 PM	37	1285.00	XCSE
GENMAB A/S	16-Apr-2025	1:49:00 PM	41	1285.00	XCSE
GENMAB A/S	16-Apr-2025	1:50:00 PM	31	1285.00	XCSE
GENMAB A/S	16-Apr-2025	1:50:04 PM	35	1285.00	XCSE
GENMAB A/S	16-Apr-2025	1:50:04 PM	42	1285.00	XCSE
GENMAB A/S	16-Apr-2025	1:51:32 PM	88	1285.50	XCSE
GENMAB A/S	16-Apr-2025	1:53:43 PM	71	1285.00	TQEX
GENMAB A/S	16-Apr-2025	1:53:43 PM	90	1285.00	CEUX
GENMAB A/S	16-Apr-2025	1:53:49 PM	15	1285.50	CEUX

163

Exhibit 99.1(a)

APPENDIX Share buy-back programme - Specification for April 14 – April 18, 2025

GENMAB A/S	16-Apr-2025	1:53:55 PM	15	1285.50	CEUX
GENMAB A/S	16-Apr-2025	1:53:56 PM	12	1285.50	CEUX
GENMAB A/S	16-Apr-2025	1:54:25 PM	15	1285.50	CEUX
GENMAB A/S	16-Apr-2025	1:55:39 PM	39	1286.50	XCSE
GENMAB A/S	16-Apr-2025	1:55:39 PM	15	1286.50	XCSE
GENMAB A/S	16-Apr-2025	1:55:39 PM	37	1286.50	XCSE
GENMAB A/S	16-Apr-2025	1:55:39 PM	26	1286.50	XCSE
GENMAB A/S	16-Apr-2025	1:55:40 PM	91	1286.50	XCSE
GENMAB A/S	16-Apr-2025	1:55:40 PM	2	1286.50	AQEU
GENMAB A/S	16-Apr-2025	1:55:40 PM	22	1286.50	AQEU
GENMAB A/S	16-Apr-2025	1:55:40 PM	90	1286.50	CEUX
GENMAB A/S	16-Apr-2025	1:55:45 PM	35	1286.50	XCSE
GENMAB A/S	16-Apr-2025	1:55:45 PM	15	1286.50	XCSE
GENMAB A/S	16-Apr-2025	1:55:45 PM	39	1286.50	XCSE
GENMAB A/S	16-Apr-2025	1:55:45 PM	24	1286.50	XCSE
GENMAB A/S	16-Apr-2025	1:55:45 PM	4	1286.50	XCSE
GENMAB A/S	16-Apr-2025	1:55:45 PM	24	1286.50	XCSE
GENMAB A/S	16-Apr-2025	1:55:45 PM	45	1286.50	XCSE
GENMAB A/S	16-Apr-2025	1:55:45 PM	15	1286.50	AQEU
GENMAB A/S	16-Apr-2025	1:55:45 PM	49	1286.50	AQEU
GENMAB A/S	16-Apr-2025	1:55:45 PM	36	1286.50	CEUX
GENMAB A/S	16-Apr-2025	1:56:01 PM	26	1286.50	XCSE
GENMAB A/S	16-Apr-2025	1:56:01 PM	39	1286.50	XCSE
GENMAB A/S	16-Apr-2025	1:56:01 PM	11	1286.50	XCSE
GENMAB A/S	16-Apr-2025	1:56:01 PM	26	1286.50	XCSE
GENMAB A/S	16-Apr-2025	1:56:01 PM	67	1286.00	TQEX
GENMAB A/S	16-Apr-2025	1:56:01 PM	36	1286.50	CEUX
GENMAB A/S	16-Apr-2025	1:56:13 PM	35	1286.50	XCSE
GENMAB A/S	16-Apr-2025	1:56:13 PM	26	1286.50	XCSE
GENMAB A/S	16-Apr-2025	1:56:13 PM	36	1286.50	CEUX
GENMAB A/S	16-Apr-2025	1:56:13 PM	51	1286.50	CEUX
GENMAB A/S	16-Apr-2025	1:58:35 PM	10	1286.00	TQEX
GENMAB A/S	16-Apr-2025	2:04:25 PM	86	1286.50	CEUX
GENMAB A/S	16-Apr-2025	2:06:03 PM	91	1286.50	XCSE
GENMAB A/S	16-Apr-2025	2:06:03 PM	2	1286.50	XCSE
GENMAB A/S	16-Apr-2025	2:06:03 PM	73	1286.50	TQEX
GENMAB A/S	16-Apr-2025	2:06:03 PM	61	1286.00	TQEX
GENMAB A/S	16-Apr-2025	2:06:03 PM	93	1286.50	AQEU
GENMAB A/S	16-Apr-2025	2:06:03 PM	30	1287.00	CEUX
GENMAB A/S	16-Apr-2025	2:06:03 PM	5	1286.50	CEUX
GENMAB A/S	16-Apr-2025	2:06:04 PM	44	1286.50	XCSE
GENMAB A/S	16-Apr-2025	2:06:04 PM	16	1286.50	XCSE
GENMAB A/S	16-Apr-2025	2:06:05 PM	17	1286.50	CEUX

164

Exhibit 99.1(a)

APPENDIX Share buy-back programme - Specification for April 14 – April 18, 2025

GENMAB A/S	16-Apr-2025	2:06:05 PM	36	1286.50	CEUX
GENMAB A/S	16-Apr-2025	2:06:06 PM	36	1286.50	CEUX
GENMAB A/S	16-Apr-2025	2:06:14 PM	15	1286.50	CEUX
GENMAB A/S	16-Apr-2025	2:06:27 PM	92	1285.50	XCSE
GENMAB A/S	16-Apr-2025	2:06:27 PM	91	1284.50	XCSE
GENMAB A/S	16-Apr-2025	2:06:27 PM	92	1283.00	XCSE
GENMAB A/S	16-Apr-2025	2:06:27 PM	88	1281.50	XCSE
GENMAB A/S	16-Apr-2025	2:06:27 PM	35	1282.00	XCSE
GENMAB A/S	16-Apr-2025	2:06:27 PM	13	1282.00	XCSE
GENMAB A/S	16-Apr-2025	2:06:27 PM	31	1282.00	XCSE
GENMAB A/S	16-Apr-2025	2:06:27 PM	9	1282.50	XCSE
GENMAB A/S	16-Apr-2025	2:06:27 PM	35	1281.00	XCSE
GENMAB A/S	16-Apr-2025	2:06:27 PM	35	1281.50	XCSE
GENMAB A/S	16-Apr-2025	2:06:27 PM	17	1281.50	XCSE
GENMAB A/S	16-Apr-2025	2:06:27 PM	14	1281.50	XCSE
GENMAB A/S	16-Apr-2025	2:06:27 PM	13	1281.50	XCSE
GENMAB A/S	16-Apr-2025	2:06:27 PM	3	1282.00	XCSE
GENMAB A/S	16-Apr-2025	2:06:27 PM	2	1280.00	XCSE
GENMAB A/S	16-Apr-2025	2:06:27 PM	10	1280.00	XCSE
GENMAB A/S	16-Apr-2025	2:06:27 PM	77	1280.00	XCSE
GENMAB A/S	16-Apr-2025	2:06:27 PM	87	1279.00	XCSE
GENMAB A/S	16-Apr-2025	2:06:27 PM	8	1277.50	XCSE
GENMAB A/S	16-Apr-2025	2:06:27 PM	2	1277.50	XCSE
GENMAB A/S	16-Apr-2025	2:06:27 PM	79	1277.50	XCSE
GENMAB A/S	16-Apr-2025	2:06:27 PM	48	1286.00	TQEX
GENMAB A/S	16-Apr-2025	2:06:27 PM	20	1285.00	TQEX
GENMAB A/S	16-Apr-2025	2:06:27 PM	75	1284.00	TQEX
GENMAB A/S	16-Apr-2025	2:06:27 PM	90	1285.50	AQEU
GENMAB A/S	16-Apr-2025	2:06:27 PM	89	1284.50	AQEU
GENMAB A/S	16-Apr-2025	2:06:27 PM	86	1283.50	AQEU
GENMAB A/S	16-Apr-2025	2:06:27 PM	28	1284.50	AQEU
GENMAB A/S	16-Apr-2025	2:06:27 PM	93	1285.50	CEUX
GENMAB A/S	16-Apr-2025	2:06:27 PM	87	1284.50	CEUX
GENMAB A/S	16-Apr-2025	2:06:27 PM	89	1283.00	CEUX
GENMAB A/S	16-Apr-2025	2:06:27 PM	36	1285.50	CEUX
GENMAB A/S	16-Apr-2025	2:06:27 PM	21	1286.00	CEUX
GENMAB A/S	16-Apr-2025	2:06:27 PM	7	1286.00	CEUX
GENMAB A/S	16-Apr-2025	2:06:27 PM	50	1284.50	CEUX
GENMAB A/S	16-Apr-2025	2:06:27 PM	8	1284.50	CEUX
GENMAB A/S	16-Apr-2025	2:06:27 PM	31	1284.50	CEUX
GENMAB A/S	16-Apr-2025	2:06:27 PM	93	1283.00	CEUX
GENMAB A/S	16-Apr-2025	2:06:27 PM	93	1281.50	CEUX
GENMAB A/S	16-Apr-2025	2:06:27 PM	28	1280.00	CEUX

165

Exhibit 99.1(a)

APPENDIX Share buy-back programme - Specification for April 14 – April 18, 2025

GENMAB A/S	16-Apr-2025	2:06:27 PM	27	1280.00	CEUX
GENMAB A/S	16-Apr-2025	2:06:27 PM	17	1280.00	CEUX
GENMAB A/S	16-Apr-2025	2:06:27 PM	18	1280.00	CEUX
GENMAB A/S	16-Apr-2025	2:06:27 PM	3	1280.00	CEUX
GENMAB A/S	16-Apr-2025	2:06:28 PM	117	1279.00	CEUX
GENMAB A/S	16-Apr-2025	2:06:29 PM	91	1280.00	XCSE
GENMAB A/S	16-Apr-2025	2:06:30 PM	89	1280.50	XCSE
GENMAB A/S	16-Apr-2025	2:06:30 PM	35	1280.00	XCSE
GENMAB A/S	16-Apr-2025	2:06:30 PM	44	1280.00	XCSE
GENMAB A/S	16-Apr-2025	2:06:30 PM	15	1280.00	XCSE
GENMAB A/S	16-Apr-2025	2:06:30 PM	23	1280.00	XCSE
GENMAB A/S	16-Apr-2025	2:06:30 PM	41	1280.00	CEUX
GENMAB A/S	16-Apr-2025	2:06:30 PM	52	1280.00	CEUX
GENMAB A/S	16-Apr-2025	2:06:31 PM	35	1280.00	XCSE
GENMAB A/S	16-Apr-2025	2:06:32 PM	13	1280.50	XCSE
GENMAB A/S	16-Apr-2025	2:06:32 PM	13	1280.50	XCSE
GENMAB A/S	16-Apr-2025	2:06:32 PM	39	1280.50	XCSE
GENMAB A/S	16-Apr-2025	2:06:32 PM	31	1280.50	XCSE
GENMAB A/S	16-Apr-2025	2:06:32 PM	39	1280.50	XCSE
GENMAB A/S	16-Apr-2025	2:06:32 PM	36	1280.50	XCSE
GENMAB A/S	16-Apr-2025	2:06:32 PM	93	1280.00	CEUX
GENMAB A/S	16-Apr-2025	2:06:33 PM	89	1280.00	XCSE
GENMAB A/S	16-Apr-2025	2:06:33 PM	35	1280.00	XCSE
GENMAB A/S	16-Apr-2025	2:06:33 PM	39	1280.00	XCSE
GENMAB A/S	16-Apr-2025	2:06:33 PM	43	1280.00	XCSE
GENMAB A/S	16-Apr-2025	2:06:33 PM	88	1280.00	CEUX
GENMAB A/S	16-Apr-2025	2:06:47 PM	100	1280.00	XCSE
GENMAB A/S	16-Apr-2025	2:06:47 PM	17	1280.00	XCSE
GENMAB A/S	16-Apr-2025	2:07:05 PM	15	1280.00	XCSE
GENMAB A/S	16-Apr-2025	2:07:05 PM	36	1280.00	XCSE
GENMAB A/S	16-Apr-2025	2:07:06 PM	13	1280.00	XCSE
GENMAB A/S	16-Apr-2025	2:07:06 PM	37	1280.00	XCSE
GENMAB A/S	16-Apr-2025	2:07:29 PM	25	1280.00	XCSE
GENMAB A/S	16-Apr-2025	2:07:29 PM	15	1280.00	XCSE
GENMAB A/S	16-Apr-2025	2:08:03 PM	39	1280.00	XCSE
GENMAB A/S	16-Apr-2025	2:08:04 PM	3	1280.00	XCSE
GENMAB A/S	16-Apr-2025	2:08:04 PM	39	1280.00	XCSE
GENMAB A/S	16-Apr-2025	2:08:06 PM	2	1280.00	XCSE
GENMAB A/S	16-Apr-2025	2:08:06 PM	39	1280.00	XCSE
GENMAB A/S	16-Apr-2025	2:08:06 PM	14	1280.00	XCSE
GENMAB A/S	16-Apr-2025	2:08:06 PM	14	1280.00	XCSE
GENMAB A/S	16-Apr-2025	2:08:06 PM	93	1279.00	XCSE
GENMAB A/S	16-Apr-2025	2:08:06 PM	11	1279.00	CEUX

166

Exhibit 99.1(a)

APPENDIX Share buy-back programme - Specification for April 14 – April 18, 2025

GENMAB A/S	16-Apr-2025	2:08:06 PM	21	1279.00	CEUX
GENMAB A/S	16-Apr-2025	2:08:57 PM	6	1280.50	XCSE
GENMAB A/S	16-Apr-2025	2:08:57 PM	80	1280.50	XCSE
GENMAB A/S	16-Apr-2025	2:10:12 PM	91	1283.50	XCSE
GENMAB A/S	16-Apr-2025	2:11:01 PM	35	1284.00	XCSE
GENMAB A/S	16-Apr-2025	2:11:26 PM	25	1284.00	XCSE
GENMAB A/S	16-Apr-2025	2:11:26 PM	35	1284.00	XCSE
GENMAB A/S	16-Apr-2025	2:11:35 PM	17	1284.00	XCSE
GENMAB A/S	16-Apr-2025	2:11:35 PM	25	1284.00	XCSE
GENMAB A/S	16-Apr-2025	2:11:35 PM	35	1284.00	XCSE
GENMAB A/S	16-Apr-2025	2:11:35 PM	39	1284.00	XCSE
GENMAB A/S	16-Apr-2025	2:11:35 PM	14	1283.00	XCSE
GENMAB A/S	16-Apr-2025	2:11:35 PM	26	1283.00	XCSE
GENMAB A/S	16-Apr-2025	2:11:35 PM	26	1283.00	AQEU
GENMAB A/S	16-Apr-2025	2:11:35 PM	15	1283.50	CEUX
GENMAB A/S	16-Apr-2025	2:11:35 PM	86	1283.00	CEUX
GENMAB A/S	16-Apr-2025	2:12:27 PM	89	1282.50	XCSE
GENMAB A/S	16-Apr-2025	2:12:27 PM	26	1282.50	XCSE
GENMAB A/S	16-Apr-2025	2:12:27 PM	39	1282.50	XCSE
GENMAB A/S	16-Apr-2025	2:12:27 PM	9	1282.50	XCSE
GENMAB A/S	16-Apr-2025	2:12:27 PM	35	1282.00	XCSE
GENMAB A/S	16-Apr-2025	2:12:27 PM	8	1282.00	XCSE
GENMAB A/S	16-Apr-2025	2:12:27 PM	62	1282.00	XCSE
GENMAB A/S	16-Apr-2025	2:12:27 PM	35	1282.00	XCSE
GENMAB A/S	16-Apr-2025	2:12:27 PM	13	1282.00	XCSE
GENMAB A/S	16-Apr-2025	2:12:27 PM	7	1282.00	XCSE
GENMAB A/S	16-Apr-2025	2:12:27 PM	13	1282.00	XCSE
GENMAB A/S	16-Apr-2025	2:12:27 PM	39	1282.00	XCSE
GENMAB A/S	16-Apr-2025	2:12:27 PM	15	1282.00	XCSE
GENMAB A/S	16-Apr-2025	2:12:27 PM	89	1282.00	CEUX
GENMAB A/S	16-Apr-2025	2:12:30 PM	35	1282.00	XCSE
GENMAB A/S	16-Apr-2025	2:12:30 PM	39	1282.00	XCSE
GENMAB A/S	16-Apr-2025	2:12:31 PM	35	1281.50	XCSE
GENMAB A/S	16-Apr-2025	2:12:31 PM	35	1282.00	XCSE
GENMAB A/S	16-Apr-2025	2:12:31 PM	39	1282.00	XCSE
GENMAB A/S	16-Apr-2025	2:12:31 PM	8	1282.00	XCSE
GENMAB A/S	16-Apr-2025	2:13:04 PM	35	1283.00	XCSE
GENMAB A/S	16-Apr-2025	2:13:10 PM	23	1284.00	XCSE
GENMAB A/S	16-Apr-2025	2:13:10 PM	16	1284.00	XCSE
GENMAB A/S	16-Apr-2025	2:13:10 PM	14	1284.00	XCSE
GENMAB A/S	16-Apr-2025	2:13:10 PM	15	1284.00	XCSE
GENMAB A/S	16-Apr-2025	2:13:11 PM	39	1284.00	XCSE
GENMAB A/S	16-Apr-2025	2:13:11 PM	19	1284.00	XCSE

167

Exhibit 99.1(a)

APPENDIX Share buy-back programme - Specification for April 14 – April 18, 2025

GENMAB A/S	16-Apr-2025	2:13:11 PM	9	1284.00	XCSE
GENMAB A/S	16-Apr-2025	2:15:15 PM	86	1285.00	XCSE
GENMAB A/S	16-Apr-2025	2:17:15 PM	91	1284.50	CEUX
GENMAB A/S	16-Apr-2025	2:18:00 PM	3	1285.00	XCSE
GENMAB A/S	16-Apr-2025	2:18:32 PM	91	1284.00	XCSE
GENMAB A/S	16-Apr-2025	2:18:32 PM	32	1284.00	XCSE
GENMAB A/S	16-Apr-2025	2:18:32 PM	28	1284.50	XCSE
GENMAB A/S	16-Apr-2025	2:18:32 PM	39	1284.50	XCSE
GENMAB A/S	16-Apr-2025	2:18:32 PM	18	1284.50	XCSE
GENMAB A/S	16-Apr-2025	2:18:32 PM	28	1284.50	XCSE
GENMAB A/S	16-Apr-2025	2:18:32 PM	39	1284.50	XCSE
GENMAB A/S	16-Apr-2025	2:18:32 PM	14	1284.50	TQEX
GENMAB A/S	16-Apr-2025	2:18:32 PM	12	1284.50	TQEX
GENMAB A/S	16-Apr-2025	2:18:32 PM	26	1284.00	AQEU
GENMAB A/S	16-Apr-2025	2:18:32 PM	25	1284.50	CEUX
GENMAB A/S	16-Apr-2025	2:18:32 PM	36	1284.50	CEUX
GENMAB A/S	16-Apr-2025	2:18:32 PM	51	1284.50	CEUX
GENMAB A/S	16-Apr-2025	2:18:35 PM	19	1284.50	XCSE
GENMAB A/S	16-Apr-2025	2:18:35 PM	35	1284.50	XCSE
GENMAB A/S	16-Apr-2025	2:19:31 PM	27	1284.50	CEUX
GENMAB A/S	16-Apr-2025	2:19:55 PM	88	1284.50	XCSE
GENMAB A/S	16-Apr-2025	2:19:55 PM	44	1284.50	CEUX
GENMAB A/S	16-Apr-2025	2:21:15 PM	48	1284.50	CEUX
GENMAB A/S	16-Apr-2025	2:22:55 PM	90	1285.00	XCSE
GENMAB A/S	16-Apr-2025	2:22:55 PM	39	1285.50	XCSE
GENMAB A/S	16-Apr-2025	2:22:55 PM	30	1285.50	XCSE
GENMAB A/S	16-Apr-2025	2:22:55 PM	18	1285.50	XCSE
GENMAB A/S	16-Apr-2025	2:22:55 PM	30	1285.50	XCSE
GENMAB A/S	16-Apr-2025	2:22:55 PM	33	1285.00	AQEU
GENMAB A/S	16-Apr-2025	2:22:55 PM	93	1285.00	CEUX
GENMAB A/S	16-Apr-2025	2:22:59 PM	8	1285.50	XCSE
GENMAB A/S	16-Apr-2025	2:22:59 PM	1	1285.50	XCSE
GENMAB A/S	16-Apr-2025	2:26:53 PM	40	1287.00	CEUX
GENMAB A/S	16-Apr-2025	2:26:53 PM	18	1287.00	CEUX
GENMAB A/S	16-Apr-2025	2:26:53 PM	18	1287.00	CEUX
GENMAB A/S	16-Apr-2025	2:26:53 PM	12	1287.00	CEUX
GENMAB A/S	16-Apr-2025	2:26:53 PM	45	1286.50	CEUX
GENMAB A/S	16-Apr-2025	2:28:23 PM	23	1287.50	XCSE
GENMAB A/S	16-Apr-2025	2:28:23 PM	21	1287.50	CEUX
GENMAB A/S	16-Apr-2025	2:28:49 PM	6	1288.00	CEUX
GENMAB A/S	16-Apr-2025	2:28:49 PM	3	1288.00	CEUX
GENMAB A/S	16-Apr-2025	2:28:49 PM	12	1288.00	CEUX
GENMAB A/S	16-Apr-2025	2:29:11 PM	8	1288.00	XCSE

168

Exhibit 99.1(a)

APPENDIX Share buy-back programme - Specification for April 14 – April 18, 2025

GENMAB A/S	16-Apr-2025	2:30:08 PM	9	1288.50	CEUX
GENMAB A/S	16-Apr-2025	2:30:08 PM	7	1288.50	CEUX
GENMAB A/S	16-Apr-2025	2:31:09 PM	29	1289.50	XCSE
GENMAB A/S	16-Apr-2025	2:31:09 PM	52	1289.00	XCSE
GENMAB A/S	16-Apr-2025	2:31:09 PM	38	1289.00	XCSE
GENMAB A/S	16-Apr-2025	2:31:09 PM	62	1289.00	TQEX
GENMAB A/S	16-Apr-2025	2:31:09 PM	49	1288.50	AQEU
GENMAB A/S	16-Apr-2025	2:31:09 PM	91	1288.50	CEUX
GENMAB A/S	16-Apr-2025	2:31:09 PM	15	1289.00	CEUX
GENMAB A/S	16-Apr-2025	2:32:17 PM	87	1289.00	XCSE
GENMAB A/S	16-Apr-2025	2:32:17 PM	13	1289.00	CEUX
GENMAB A/S	16-Apr-2025	2:32:17 PM	30	1289.00	CEUX
GENMAB A/S	16-Apr-2025	2:32:17 PM	46	1289.00	CEUX
GENMAB A/S	16-Apr-2025	2:32:18 PM	27	1289.00	XCSE
GENMAB A/S	16-Apr-2025	2:32:18 PM	41	1289.00	XCSE
GENMAB A/S	16-Apr-2025	2:32:18 PM	30	1289.00	XCSE
GENMAB A/S	16-Apr-2025	2:32:18 PM	14	1289.00	TQEX
GENMAB A/S	16-Apr-2025	2:32:18 PM	34	1289.00	CEUX
GENMAB A/S	16-Apr-2025	2:33:12 PM	88	1290.00	XCSE
GENMAB A/S	16-Apr-2025	2:33:12 PM	39	1290.00	XCSE
GENMAB A/S	16-Apr-2025	2:33:12 PM	44	1290.00	XCSE
GENMAB A/S	16-Apr-2025	2:33:12 PM	41	1290.00	TQEX
GENMAB A/S	16-Apr-2025	2:33:12 PM	39	1290.50	AQEU
GENMAB A/S	16-Apr-2025	2:33:12 PM	90	1290.00	CEUX
GENMAB A/S	16-Apr-2025	2:33:16 PM	87	1289.00	XCSE
GENMAB A/S	16-Apr-2025	2:33:16 PM	39	1289.00	XCSE
GENMAB A/S	16-Apr-2025	2:33:16 PM	13	1289.00	XCSE
GENMAB A/S	16-Apr-2025	2:33:16 PM	39	1289.50	XCSE
GENMAB A/S	16-Apr-2025	2:33:16 PM	18	1289.50	XCSE
GENMAB A/S	16-Apr-2025	2:33:16 PM	8	1289.50	XCSE
GENMAB A/S	16-Apr-2025	2:33:16 PM	39	1289.00	XCSE
GENMAB A/S	16-Apr-2025	2:33:16 PM	15	1289.00	XCSE
GENMAB A/S	16-Apr-2025	2:33:16 PM	44	1289.00	XCSE
GENMAB A/S	16-Apr-2025	2:33:16 PM	12	1289.00	TQEX
GENMAB A/S	16-Apr-2025	2:33:16 PM	40	1289.50	AQEU
GENMAB A/S	16-Apr-2025	2:33:16 PM	92	1288.50	CEUX
GENMAB A/S	16-Apr-2025	2:35:25 PM	1	1291.50	XCSE
GENMAB A/S	16-Apr-2025	2:35:25 PM	2	1291.50	XCSE
GENMAB A/S	16-Apr-2025	2:37:03 PM	41	1291.50	XCSE
GENMAB A/S	16-Apr-2025	2:37:03 PM	46	1291.50	XCSE
GENMAB A/S	16-Apr-2025	2:37:03 PM	37	1291.50	AQEU
GENMAB A/S	16-Apr-2025	2:37:03 PM	91	1291.50	CEUX
GENMAB A/S	16-Apr-2025	2:38:24 PM	35	1291.50	XCSE

169

Exhibit 99.1(a)

APPENDIX Share buy-back programme - Specification for April 14 – April 18, 2025

GENMAB A/S	16-Apr-2025	2:38:24 PM	39	1291.50	XCSE
GENMAB A/S	16-Apr-2025	2:38:24 PM	27	1291.50	XCSE
GENMAB A/S	16-Apr-2025	2:38:24 PM	16	1291.50	XCSE
GENMAB A/S	16-Apr-2025	2:38:24 PM	35	1291.00	XCSE
GENMAB A/S	16-Apr-2025	2:38:24 PM	15	1291.00	XCSE
GENMAB A/S	16-Apr-2025	2:38:24 PM	36	1291.00	XCSE
GENMAB A/S	16-Apr-2025	2:38:24 PM	86	1290.50	XCSE
GENMAB A/S	16-Apr-2025	2:38:24 PM	26	1290.50	TQEX
GENMAB A/S	16-Apr-2025	2:38:24 PM	38	1290.50	AQEU
GENMAB A/S	16-Apr-2025	2:38:24 PM	34	1291.50	CEUX
GENMAB A/S	16-Apr-2025	2:38:24 PM	90	1290.50	CEUX
GENMAB A/S	16-Apr-2025	2:39:49 PM	27	1290.00	XCSE
GENMAB A/S	16-Apr-2025	2:39:49 PM	16	1290.00	XCSE
GENMAB A/S	16-Apr-2025	2:39:49 PM	37	1290.00	XCSE
GENMAB A/S	16-Apr-2025	2:39:49 PM	16	1289.50	TQEX
GENMAB A/S	16-Apr-2025	2:39:49 PM	10	1289.50	TQEX
GENMAB A/S	16-Apr-2025	2:39:49 PM	83	1289.50	CEUX
GENMAB A/S	16-Apr-2025	2:39:49 PM	8	1289.50	CEUX
GENMAB A/S	16-Apr-2025	2:40:12 PM	13	1290.00	XCSE
GENMAB A/S	16-Apr-2025	2:40:12 PM	22	1290.00	XCSE
GENMAB A/S	16-Apr-2025	2:40:12 PM	2	1290.00	XCSE
GENMAB A/S	16-Apr-2025	2:40:15 PM	39	1290.00	XCSE
GENMAB A/S	16-Apr-2025	2:40:15 PM	17	1290.00	XCSE
GENMAB A/S	16-Apr-2025	2:40:15 PM	35	1290.00	XCSE
GENMAB A/S	16-Apr-2025	2:40:15 PM	26	1290.00	XCSE
GENMAB A/S	16-Apr-2025	2:40:15 PM	13	1290.00	XCSE
GENMAB A/S	16-Apr-2025	2:40:15 PM	13	1290.00	XCSE
GENMAB A/S	16-Apr-2025	2:40:15 PM	14	1290.00	XCSE
GENMAB A/S	16-Apr-2025	2:41:11 PM	18	1290.00	XCSE
GENMAB A/S	16-Apr-2025	2:41:11 PM	35	1290.00	XCSE
GENMAB A/S	16-Apr-2025	2:41:11 PM	39	1290.00	XCSE
GENMAB A/S	16-Apr-2025	2:41:11 PM	25	1290.00	XCSE
GENMAB A/S	16-Apr-2025	2:41:12 PM	13	1290.00	XCSE
GENMAB A/S	16-Apr-2025	2:41:12 PM	39	1290.00	XCSE
GENMAB A/S	16-Apr-2025	2:41:12 PM	37	1290.00	XCSE
GENMAB A/S	16-Apr-2025	2:41:12 PM	13	1290.00	XCSE
GENMAB A/S	16-Apr-2025	2:41:12 PM	15	1290.00	XCSE
GENMAB A/S	16-Apr-2025	2:41:12 PM	39	1290.00	XCSE
GENMAB A/S	16-Apr-2025	2:41:12 PM	47	1290.00	XCSE
GENMAB A/S	16-Apr-2025	2:41:12 PM	15	1290.00	XCSE
GENMAB A/S	16-Apr-2025	2:41:12 PM	16	1290.00	XCSE
GENMAB A/S	16-Apr-2025	2:41:12 PM	16	1290.00	XCSE
GENMAB A/S	16-Apr-2025	2:41:12 PM	47	1290.00	XCSE

170

Exhibit 99.1(a)

APPENDIX Share buy-back programme - Specification for April 14 – April 18, 2025

GENMAB A/S	16-Apr-2025	2:41:12 PM	14	1290.00	XCSE
GENMAB A/S	16-Apr-2025	2:41:14 PM	39	1290.00	XCSE
GENMAB A/S	16-Apr-2025	2:41:14 PM	47	1290.00	XCSE
GENMAB A/S	16-Apr-2025	2:41:14 PM	31	1290.00	XCSE
GENMAB A/S	16-Apr-2025	2:41:14 PM	31	1289.50	CEUX
GENMAB A/S	16-Apr-2025	2:41:14 PM	52	1289.50	CEUX
GENMAB A/S	16-Apr-2025	2:41:17 PM	39	1290.00	XCSE
GENMAB A/S	16-Apr-2025	2:41:17 PM	47	1290.00	XCSE
GENMAB A/S	16-Apr-2025	2:41:17 PM	31	1290.00	XCSE
GENMAB A/S	16-Apr-2025	2:41:17 PM	10	1289.50	CEUX
GENMAB A/S	16-Apr-2025	2:41:18 PM	47	1290.00	XCSE
GENMAB A/S	16-Apr-2025	2:41:20 PM	39	1290.00	XCSE
GENMAB A/S	16-Apr-2025	2:41:20 PM	37	1290.00	XCSE
GENMAB A/S	16-Apr-2025	2:41:20 PM	41	1290.00	XCSE
GENMAB A/S	16-Apr-2025	2:42:59 PM	12	1290.00	XCSE
GENMAB A/S	16-Apr-2025	2:44:27 PM	10	1289.00	XCSE
GENMAB A/S	16-Apr-2025	2:44:27 PM	81	1289.00	XCSE
GENMAB A/S	16-Apr-2025	2:44:27 PM	35	1289.50	XCSE
GENMAB A/S	16-Apr-2025	2:44:27 PM	14	1289.50	XCSE
GENMAB A/S	16-Apr-2025	2:44:27 PM	36	1289.50	XCSE
GENMAB A/S	16-Apr-2025	2:44:27 PM	29	1289.50	CEUX
GENMAB A/S	16-Apr-2025	2:44:27 PM	85	1289.00	CEUX
GENMAB A/S	16-Apr-2025	2:44:29 PM	93	1289.50	XCSE
GENMAB A/S	16-Apr-2025	2:45:25 PM	6	1289.00	CEUX
GENMAB A/S	16-Apr-2025	2:46:45 PM	88	1289.50	XCSE
GENMAB A/S	16-Apr-2025	2:47:42 PM	39	1289.50	XCSE
GENMAB A/S	16-Apr-2025	2:47:42 PM	22	1289.50	XCSE
GENMAB A/S	16-Apr-2025	2:47:42 PM	35	1289.50	XCSE
GENMAB A/S	16-Apr-2025	2:47:42 PM	2	1289.50	XCSE
GENMAB A/S	16-Apr-2025	2:47:42 PM	19	1289.50	XCSE
GENMAB A/S	16-Apr-2025	2:47:42 PM	44	1289.00	CEUX
GENMAB A/S	16-Apr-2025	2:47:42 PM	48	1289.00	CEUX
GENMAB A/S	16-Apr-2025	2:48:16 PM	39	1289.50	XCSE
GENMAB A/S	16-Apr-2025	2:48:16 PM	12	1289.50	XCSE
GENMAB A/S	16-Apr-2025	2:48:16 PM	45	1289.50	XCSE
GENMAB A/S	16-Apr-2025	2:48:16 PM	21	1289.50	XCSE
GENMAB A/S	16-Apr-2025	2:48:25 PM	39	1289.50	XCSE
GENMAB A/S	16-Apr-2025	2:48:25 PM	45	1289.50	XCSE
GENMAB A/S	16-Apr-2025	2:48:25 PM	33	1289.50	XCSE
GENMAB A/S	16-Apr-2025	2:48:33 PM	49	1289.50	TQEX
GENMAB A/S	16-Apr-2025	2:48:34 PM	35	1289.50	XCSE
GENMAB A/S	16-Apr-2025	2:48:34 PM	15	1289.50	XCSE
GENMAB A/S	16-Apr-2025	2:48:34 PM	45	1289.50	XCSE

171

Exhibit 99.1(a)

APPENDIX Share buy-back programme - Specification for April 14 – April 18, 2025

GENMAB A/S	16-Apr-2025	2:48:34 PM	16	1289.50	TQEX
GENMAB A/S	16-Apr-2025	2:48:34 PM	32	1289.50	CEUX
GENMAB A/S	16-Apr-2025	2:48:35 PM	90	1289.00	XCSE
GENMAB A/S	16-Apr-2025	2:48:43 PM	35	1289.00	XCSE
GENMAB A/S	16-Apr-2025	2:48:43 PM	45	1289.00	XCSE
GENMAB A/S	16-Apr-2025	2:49:05 PM	28	1288.50	TQEX
GENMAB A/S	16-Apr-2025	2:49:11 PM	10	1288.50	AQEU
GENMAB A/S	16-Apr-2025	2:49:35 PM	16	1288.50	AQEU
GENMAB A/S	16-Apr-2025	2:49:40 PM	93	1288.00	XCSE
GENMAB A/S	16-Apr-2025	2:49:40 PM	36	1288.50	CEUX
GENMAB A/S	16-Apr-2025	2:49:41 PM	80	1288.00	CEUX
GENMAB A/S	16-Apr-2025	2:49:41 PM	11	1288.00	CEUX
GENMAB A/S	16-Apr-2025	2:49:42 PM	34	1288.00	XCSE
GENMAB A/S	16-Apr-2025	2:49:49 PM	12	1288.50	XCSE
GENMAB A/S	16-Apr-2025	2:49:49 PM	39	1288.50	XCSE
GENMAB A/S	16-Apr-2025	2:49:49 PM	17	1288.50	XCSE
GENMAB A/S	16-Apr-2025	2:50:10 PM	18	1288.00	CEUX
GENMAB A/S	16-Apr-2025	2:51:15 PM	87	1288.00	XCSE
GENMAB A/S	16-Apr-2025	2:51:15 PM	71	1288.00	CEUX
GENMAB A/S	16-Apr-2025	2:51:44 PM	16	1289.00	XCSE
GENMAB A/S	16-Apr-2025	2:52:05 PM	14	1289.00	XCSE
GENMAB A/S	16-Apr-2025	2:53:00 PM	3	1289.00	XCSE
GENMAB A/S	16-Apr-2025	2:53:00 PM	30	1289.00	XCSE
GENMAB A/S	16-Apr-2025	2:53:15 PM	93	1288.50	XCSE
GENMAB A/S	16-Apr-2025	2:53:15 PM	20	1288.50	TQEX
GENMAB A/S	16-Apr-2025	2:53:15 PM	86	1288.50	CEUX
GENMAB A/S	16-Apr-2025	2:55:14 PM	1	1290.50	TQEX
GENMAB A/S	16-Apr-2025	2:55:14 PM	36	1290.50	TQEX
GENMAB A/S	16-Apr-2025	2:57:55 PM	78	1290.00	CEUX
GENMAB A/S	16-Apr-2025	2:58:00 PM	48	1290.50	XCSE
GENMAB A/S	16-Apr-2025	2:58:00 PM	2	1290.50	XCSE
GENMAB A/S	16-Apr-2025	2:58:00 PM	17	1290.50	CEUX
GENMAB A/S	16-Apr-2025	2:58:15 PM	7	1290.50	TQEX
GENMAB A/S	16-Apr-2025	2:58:16 PM	31	1290.50	TQEX
GENMAB A/S	16-Apr-2025	2:58:16 PM	11	1291.00	CEUX
GENMAB A/S	16-Apr-2025	2:59:43 PM	90	1291.00	XCSE
GENMAB A/S	16-Apr-2025	2:59:43 PM	23	1291.00	CEUX
GENMAB A/S	16-Apr-2025	2:59:43 PM	70	1291.00	CEUX
GENMAB A/S	16-Apr-2025	3:00:35 PM	49	1291.00	XCSE
GENMAB A/S	16-Apr-2025	3:00:35 PM	21	1291.00	XCSE
GENMAB A/S	16-Apr-2025	3:00:35 PM	2	1291.00	XCSE
GENMAB A/S	16-Apr-2025	3:00:35 PM	13	1290.00	CEUX
GENMAB A/S	16-Apr-2025	3:01:19 PM	37	1291.50	XCSE

172

Exhibit 99.1(a)

APPENDIX Share buy-back programme - Specification for April 14 – April 18, 2025

GENMAB A/S	16-Apr-2025	3:01:19 PM	39	1291.50	XCSE
GENMAB A/S	16-Apr-2025	3:01:20 PM	39	1291.50	XCSE
GENMAB A/S	16-Apr-2025	3:01:20 PM	37	1291.50	XCSE
GENMAB A/S	16-Apr-2025	3:01:20 PM	39	1291.50	XCSE
GENMAB A/S	16-Apr-2025	3:01:20 PM	37	1291.50	XCSE
GENMAB A/S	16-Apr-2025	3:01:20 PM	1	1290.50	TQEX
GENMAB A/S	16-Apr-2025	3:01:30 PM	87	1290.00	XCSE
GENMAB A/S	16-Apr-2025	3:01:30 PM	36	1290.50	CEUX
GENMAB A/S	16-Apr-2025	3:02:34 PM	26	1290.00	XCSE
GENMAB A/S	16-Apr-2025	3:02:34 PM	39	1290.00	XCSE
GENMAB A/S	16-Apr-2025	3:02:34 PM	21	1290.00	XCSE
GENMAB A/S	16-Apr-2025	3:02:34 PM	17	1290.00	XCSE
GENMAB A/S	16-Apr-2025	3:02:34 PM	17	1290.00	XCSE
GENMAB A/S	16-Apr-2025	3:02:34 PM	44	1289.50	TQEX
GENMAB A/S	16-Apr-2025	3:02:34 PM	42	1289.50	AQEU
GENMAB A/S	16-Apr-2025	3:05:25 PM	27	1289.50	TQEX
GENMAB A/S	16-Apr-2025	3:05:25 PM	40	1289.00	CEUX
GENMAB A/S	16-Apr-2025	3:08:22 PM	76	1291.00	CEUX
GENMAB A/S	16-Apr-2025	3:08:23 PM	38	1291.00	TQEX
GENMAB A/S	16-Apr-2025	3:08:23 PM	11	1291.00	CEUX
GENMAB A/S	16-Apr-2025	3:09:51 PM	93	1290.50	XCSE
GENMAB A/S	16-Apr-2025	3:09:51 PM	28	1291.50	TQEX
GENMAB A/S	16-Apr-2025	3:09:51 PM	74	1291.00	AQEU
GENMAB A/S	16-Apr-2025	3:09:51 PM	87	1290.00	CEUX
GENMAB A/S	16-Apr-2025	3:09:52 PM	63	1289.50	AQEU
GENMAB A/S	16-Apr-2025	3:09:52 PM	36	1290.00	CEUX
GENMAB A/S	16-Apr-2025	3:09:52 PM	7	1290.00	CEUX
GENMAB A/S	16-Apr-2025	3:09:52 PM	8	1290.00	CEUX
GENMAB A/S	16-Apr-2025	3:09:52 PM	7	1290.00	CEUX
GENMAB A/S	16-Apr-2025	3:09:52 PM	16	1290.00	CEUX
GENMAB A/S	16-Apr-2025	3:09:53 PM	36	1290.00	CEUX
GENMAB A/S	16-Apr-2025	3:09:53 PM	36	1290.00	CEUX
GENMAB A/S	16-Apr-2025	3:10:45 PM	92	1290.00	XCSE
GENMAB A/S	16-Apr-2025	3:10:45 PM	35	1290.00	TQEX
GENMAB A/S	16-Apr-2025	3:10:45 PM	17	1290.00	CEUX
GENMAB A/S	16-Apr-2025	3:10:45 PM	2	1290.00	CEUX
GENMAB A/S	16-Apr-2025	3:10:45 PM	68	1290.00	CEUX
GENMAB A/S	16-Apr-2025	3:10:58 PM	35	1290.00	XCSE
GENMAB A/S	16-Apr-2025	3:10:58 PM	17	1290.00	XCSE
GENMAB A/S	16-Apr-2025	3:10:58 PM	1	1290.00	XCSE
GENMAB A/S	16-Apr-2025	3:11:25 PM	30	1290.00	XCSE
GENMAB A/S	16-Apr-2025	3:11:55 PM	28	1290.00	XCSE
GENMAB A/S	16-Apr-2025	3:11:55 PM	48	1289.00	CEUX

173

Exhibit 99.1(a)

APPENDIX Share buy-back programme - Specification for April 14 – April 18, 2025

GENMAB A/S	16-Apr-2025	3:13:55 PM	5	1289.00	CEUX
GENMAB A/S	16-Apr-2025	3:14:58 PM	37	1289.50	AQEU
GENMAB A/S	16-Apr-2025	3:15:05 PM	88	1289.00	XCSE
GENMAB A/S	16-Apr-2025	3:15:35 PM	29	1288.50	TQEX
GENMAB A/S	16-Apr-2025	3:15:35 PM	36	1288.50	AQEU
GENMAB A/S	16-Apr-2025	3:15:35 PM	48	1288.50	CEUX
GENMAB A/S	16-Apr-2025	3:15:35 PM	38	1288.50	CEUX
GENMAB A/S	16-Apr-2025	3:15:38 PM	87	1287.50	XCSE
GENMAB A/S	16-Apr-2025	3:15:38 PM	26	1288.00	XCSE
GENMAB A/S	16-Apr-2025	3:15:38 PM	22	1288.00	XCSE
GENMAB A/S	16-Apr-2025	3:15:38 PM	17	1288.00	XCSE
GENMAB A/S	16-Apr-2025	3:15:38 PM	39	1288.50	XCSE
GENMAB A/S	16-Apr-2025	3:15:38 PM	13	1288.50	XCSE
GENMAB A/S	16-Apr-2025	3:15:38 PM	22	1288.00	XCSE
GENMAB A/S	16-Apr-2025	3:15:38 PM	17	1288.00	XCSE
GENMAB A/S	16-Apr-2025	3:15:38 PM	15	1288.00	XCSE
GENMAB A/S	16-Apr-2025	3:15:38 PM	17	1288.00	XCSE
GENMAB A/S	16-Apr-2025	3:15:38 PM	29	1287.50	TQEX
GENMAB A/S	16-Apr-2025	3:15:38 PM	93	1287.50	CEUX
GENMAB A/S	16-Apr-2025	3:16:39 PM	100	1288.00	XCSE
GENMAB A/S	16-Apr-2025	3:16:45 PM	86	1287.50	XCSE
GENMAB A/S	16-Apr-2025	3:16:45 PM	86	1287.50	CEUX
GENMAB A/S	16-Apr-2025	3:17:05 PM	86	1287.50	XCSE
GENMAB A/S	16-Apr-2025	3:17:05 PM	71	1287.50	CEUX
GENMAB A/S	16-Apr-2025	3:17:05 PM	19	1287.50	CEUX
GENMAB A/S	16-Apr-2025	3:17:11 PM	36	1287.50	CEUX
GENMAB A/S	16-Apr-2025	3:17:52 PM	4	1287.50	CEUX
GENMAB A/S	16-Apr-2025	3:18:25 PM	38	1286.50	CEUX
GENMAB A/S	16-Apr-2025	3:19:11 PM	36	1287.50	CEUX
GENMAB A/S	16-Apr-2025	3:20:15 PM	36	1287.00	AQEU
GENMAB A/S	16-Apr-2025	3:20:15 PM	36	1287.50	CEUX
GENMAB A/S	16-Apr-2025	3:20:18 PM	4	1287.50	XCSE
GENMAB A/S	16-Apr-2025	3:20:35 PM	117	1288.00	XCSE
GENMAB A/S	16-Apr-2025	3:20:35 PM	17	1287.00	AQEU
GENMAB A/S	16-Apr-2025	3:20:35 PM	51	1286.50	CEUX
GENMAB A/S	16-Apr-2025	3:20:35 PM	90	1287.50	CEUX
GENMAB A/S	16-Apr-2025	3:20:36 PM	26	1288.00	XCSE
GENMAB A/S	16-Apr-2025	3:20:36 PM	37	1288.00	XCSE
GENMAB A/S	16-Apr-2025	3:20:36 PM	5	1288.00	XCSE
GENMAB A/S	16-Apr-2025	3:20:36 PM	2	1288.50	CEUX
GENMAB A/S	16-Apr-2025	3:20:36 PM	16	1288.50	CEUX
GENMAB A/S	16-Apr-2025	3:20:37 PM	36	1288.50	CEUX
GENMAB A/S	16-Apr-2025	3:21:06 PM	37	1288.50	XCSE

174

Exhibit 99.1(a)

APPENDIX Share buy-back programme - Specification for April 14 – April 18, 2025

GENMAB A/S	16-Apr-2025	3:21:06 PM	90	1288.00	CEUX
GENMAB A/S	16-Apr-2025	3:21:09 PM	91	1287.50	XCSE
GENMAB A/S	16-Apr-2025	3:21:09 PM	37	1288.50	XCSE
GENMAB A/S	16-Apr-2025	3:21:09 PM	37	1288.50	XCSE
GENMAB A/S	16-Apr-2025	3:21:09 PM	28	1288.00	TQEX
GENMAB A/S	16-Apr-2025	3:21:12 PM	14	1288.50	XCSE
GENMAB A/S	16-Apr-2025	3:21:51 PM	89	1288.00	XCSE
GENMAB A/S	16-Apr-2025	3:21:51 PM	37	1288.50	XCSE
GENMAB A/S	16-Apr-2025	3:21:51 PM	25	1288.50	XCSE
GENMAB A/S	16-Apr-2025	3:21:51 PM	3	1288.00	AQEU
GENMAB A/S	16-Apr-2025	3:22:06 PM	37	1288.50	XCSE
GENMAB A/S	16-Apr-2025	3:22:06 PM	16	1288.50	XCSE
GENMAB A/S	16-Apr-2025	3:22:06 PM	37	1288.50	XCSE
GENMAB A/S	16-Apr-2025	3:22:06 PM	16	1288.50	XCSE
GENMAB A/S	16-Apr-2025	3:22:06 PM	7	1288.50	XCSE
GENMAB A/S	16-Apr-2025	3:22:06 PM	37	1288.50	XCSE
GENMAB A/S	16-Apr-2025	3:22:06 PM	37	1288.50	XCSE
GENMAB A/S	16-Apr-2025	3:22:06 PM	17	1288.50	XCSE
GENMAB A/S	16-Apr-2025	3:22:06 PM	37	1288.50	XCSE
GENMAB A/S	16-Apr-2025	3:22:06 PM	14	1288.50	XCSE
GENMAB A/S	16-Apr-2025	3:22:06 PM	17	1288.50	XCSE
GENMAB A/S	16-Apr-2025	3:22:06 PM	32	1288.50	XCSE
GENMAB A/S	16-Apr-2025	3:22:06 PM	21	1288.00	AQEU
GENMAB A/S	16-Apr-2025	3:22:06 PM	8	1288.00	AQEU
GENMAB A/S	16-Apr-2025	3:22:06 PM	36	1288.00	CEUX
GENMAB A/S	16-Apr-2025	3:22:07 PM	35	1288.00	XCSE
GENMAB A/S	16-Apr-2025	3:22:07 PM	15	1288.00	XCSE
GENMAB A/S	16-Apr-2025	3:22:07 PM	15	1288.00	XCSE
GENMAB A/S	16-Apr-2025	3:22:07 PM	14	1288.00	XCSE
GENMAB A/S	16-Apr-2025	3:22:07 PM	37	1288.00	XCSE
GENMAB A/S	16-Apr-2025	3:22:07 PM	1	1288.50	XCSE
GENMAB A/S	16-Apr-2025	3:22:07 PM	17	1288.00	XCSE
GENMAB A/S	16-Apr-2025	3:22:07 PM	37	1288.00	XCSE
GENMAB A/S	16-Apr-2025	3:22:07 PM	16	1288.00	XCSE
GENMAB A/S	16-Apr-2025	3:22:07 PM	16	1288.50	XCSE
GENMAB A/S	16-Apr-2025	3:22:07 PM	31	1288.50	XCSE
GENMAB A/S	16-Apr-2025	3:22:08 PM	16	1288.50	XCSE
GENMAB A/S	16-Apr-2025	3:22:08 PM	17	1288.50	XCSE
GENMAB A/S	16-Apr-2025	3:22:08 PM	37	1288.50	XCSE
GENMAB A/S	16-Apr-2025	3:22:08 PM	47	1288.50	XCSE
GENMAB A/S	16-Apr-2025	3:22:08 PM	89	1287.50	XCSE
GENMAB A/S	16-Apr-2025	3:22:45 PM	17	1287.50	XCSE
GENMAB A/S	16-Apr-2025	3:22:45 PM	12	1287.50	XCSE

175

Exhibit 99.1(a)

APPENDIX Share buy-back programme - Specification for April 14 – April 18, 2025

GENMAB A/S	16-Apr-2025	3:22:45 PM	37	1287.50	XCSE
GENMAB A/S	16-Apr-2025	3:22:45 PM	14	1287.50	XCSE
GENMAB A/S	16-Apr-2025	3:22:45 PM	37	1287.50	XCSE
GENMAB A/S	16-Apr-2025	3:22:45 PM	28	1287.00	TQEX
GENMAB A/S	16-Apr-2025	3:22:45 PM	16	1287.00	AQEU
GENMAB A/S	16-Apr-2025	3:22:45 PM	93	1287.00	CEUX
GENMAB A/S	16-Apr-2025	3:22:50 PM	8	1287.00	TQEX
GENMAB A/S	16-Apr-2025	3:22:53 PM	19	1287.00	TQEX
GENMAB A/S	16-Apr-2025	3:24:40 PM	20	1287.50	XCSE
GENMAB A/S	16-Apr-2025	3:24:42 PM	54	1287.50	XCSE
GENMAB A/S	16-Apr-2025	3:24:42 PM	19	1287.50	XCSE
GENMAB A/S	16-Apr-2025	3:25:13 PM	3	1287.50	XCSE
GENMAB A/S	16-Apr-2025	3:25:13 PM	6	1287.50	XCSE
GENMAB A/S	16-Apr-2025	3:25:13 PM	6	1287.50	XCSE
GENMAB A/S	16-Apr-2025	3:25:13 PM	4	1287.50	CEUX
GENMAB A/S	16-Apr-2025	3:25:13 PM	3	1287.00	CEUX
GENMAB A/S	16-Apr-2025	3:25:32 PM	39	1287.50	XCSE
GENMAB A/S	16-Apr-2025	3:25:32 PM	14	1287.50	XCSE
GENMAB A/S	16-Apr-2025	3:25:32 PM	34	1287.00	AQEU
GENMAB A/S	16-Apr-2025	3:25:32 PM	81	1287.00	CEUX
GENMAB A/S	16-Apr-2025	3:25:32 PM	3	1287.00	CEUX
GENMAB A/S	16-Apr-2025	3:26:49 PM	12	1287.00	CEUX
GENMAB A/S	16-Apr-2025	3:27:40 PM	36	1288.00	CEUX
GENMAB A/S	16-Apr-2025	3:27:50 PM	4	1287.50	AQEU
GENMAB A/S	16-Apr-2025	3:27:50 PM	2	1287.50	AQEU
GENMAB A/S	16-Apr-2025	3:27:50 PM	2	1287.50	AQEU
GENMAB A/S	16-Apr-2025	3:27:50 PM	2	1287.50	AQEU
GENMAB A/S	16-Apr-2025	3:27:50 PM	2	1287.50	AQEU
GENMAB A/S	16-Apr-2025	3:27:50 PM	2	1287.50	AQEU
GENMAB A/S	16-Apr-2025	3:27:58 PM	26	1287.50	AQEU
GENMAB A/S	16-Apr-2025	3:28:25 PM	80	1287.00	CEUX
GENMAB A/S	16-Apr-2025	3:29:14 PM	46	1288.00	XCSE
GENMAB A/S	16-Apr-2025	3:29:14 PM	15	1288.00	XCSE
GENMAB A/S	16-Apr-2025	3:29:16 PM	37	1288.00	XCSE
GENMAB A/S	16-Apr-2025	3:29:16 PM	16	1288.00	XCSE
GENMAB A/S	16-Apr-2025	3:29:23 PM	90	1287.00	CEUX
GENMAB A/S	16-Apr-2025	3:30:00 PM	88	1287.50	XCSE
GENMAB A/S	16-Apr-2025	3:30:00 PM	3	1287.00	XCSE
GENMAB A/S	16-Apr-2025	3:30:00 PM	3	1287.00	XCSE
GENMAB A/S	16-Apr-2025	3:30:00 PM	15	1287.50	XCSE
GENMAB A/S	16-Apr-2025	3:30:00 PM	30	1287.50	XCSE
GENMAB A/S	16-Apr-2025	3:30:00 PM	58	1287.50	TQEX
GENMAB A/S	16-Apr-2025	3:30:00 PM	4	1287.00	AQEU

176

Exhibit 99.1(a)

APPENDIX Share buy-back programme - Specification for April 14 – April 18, 2025

GENMAB A/S	16-Apr-2025	3:30:00 PM	30	1287.00	AQEU
GENMAB A/S	16-Apr-2025	3:30:00 PM	15	1287.50	CEUX
GENMAB A/S	16-Apr-2025	3:30:04 PM	3	1287.00	TQEX
GENMAB A/S	16-Apr-2025	3:30:04 PM	2	1287.00	TQEX
GENMAB A/S	16-Apr-2025	3:30:04 PM	3	1287.00	TQEX
GENMAB A/S	16-Apr-2025	3:30:04 PM	3	1288.00	CEUX
GENMAB A/S	16-Apr-2025	3:30:04 PM	20	1288.00	CEUX
GENMAB A/S	16-Apr-2025	3:30:09 PM	41	1289.50	CEUX
GENMAB A/S	16-Apr-2025	3:30:10 PM	86	1289.50	XCSE
GENMAB A/S	16-Apr-2025	3:30:13 PM	2	1289.50	XCSE
GENMAB A/S	16-Apr-2025	3:30:40 PM	16	1289.50	XCSE
GENMAB A/S	16-Apr-2025	3:30:40 PM	25	1289.50	XCSE
GENMAB A/S	16-Apr-2025	3:30:40 PM	37	1289.50	XCSE
GENMAB A/S	16-Apr-2025	3:30:40 PM	21	1288.50	XCSE
GENMAB A/S	16-Apr-2025	3:30:40 PM	2	1288.50	XCSE
GENMAB A/S	16-Apr-2025	3:30:40 PM	2	1288.50	XCSE
GENMAB A/S	16-Apr-2025	3:30:40 PM	15	1288.50	XCSE
GENMAB A/S	16-Apr-2025	3:30:40 PM	10	1288.50	XCSE
GENMAB A/S	16-Apr-2025	3:30:40 PM	7	1288.50	XCSE
GENMAB A/S	16-Apr-2025	3:30:40 PM	8	1288.50	XCSE
GENMAB A/S	16-Apr-2025	3:30:40 PM	2	1288.50	XCSE
GENMAB A/S	16-Apr-2025	3:30:40 PM	8	1288.50	XCSE
GENMAB A/S	16-Apr-2025	3:30:40 PM	13	1288.50	XCSE
GENMAB A/S	16-Apr-2025	3:30:40 PM	3	1289.00	TQEX
GENMAB A/S	16-Apr-2025	3:30:40 PM	37	1289.00	TQEX
GENMAB A/S	16-Apr-2025	3:30:40 PM	3	1288.00	TQEX
GENMAB A/S	16-Apr-2025	3:30:40 PM	3	1289.00	AQEU
GENMAB A/S	16-Apr-2025	3:30:40 PM	2	1289.00	AQEU
GENMAB A/S	16-Apr-2025	3:30:40 PM	2	1289.00	AQEU
GENMAB A/S	16-Apr-2025	3:30:40 PM	24	1289.00	AQEU
GENMAB A/S	16-Apr-2025	3:30:40 PM	15	1289.50	CEUX
GENMAB A/S	16-Apr-2025	3:30:40 PM	74	1289.00	CEUX
GENMAB A/S	16-Apr-2025	3:30:40 PM	12	1289.00	CEUX
GENMAB A/S	16-Apr-2025	3:31:04 PM	88	1287.50	XCSE
GENMAB A/S	16-Apr-2025	3:31:04 PM	20	1287.50	XCSE
GENMAB A/S	16-Apr-2025	3:31:04 PM	2	1287.50	XCSE
GENMAB A/S	16-Apr-2025	3:31:04 PM	2	1287.50	XCSE
GENMAB A/S	16-Apr-2025	3:31:04 PM	3	1287.50	XCSE
GENMAB A/S	16-Apr-2025	3:31:04 PM	2	1287.50	XCSE
GENMAB A/S	16-Apr-2025	3:31:04 PM	2	1287.50	XCSE
GENMAB A/S	16-Apr-2025	3:31:04 PM	2	1287.50	XCSE
GENMAB A/S	16-Apr-2025	3:31:04 PM	3	1287.50	XCSE
GENMAB A/S	16-Apr-2025	3:31:04 PM	15	1287.50	XCSE

177

Exhibit 99.1(a)

APPENDIX Share buy-back programme - Specification for April 14 – April 18, 2025

GENMAB A/S	16-Apr-2025	3:31:04 PM	37	1287.50	XCSE
GENMAB A/S	16-Apr-2025	3:31:04 PM	29	1288.00	XCSE
GENMAB A/S	16-Apr-2025	3:31:04 PM	35	1288.00	TQEX
GENMAB A/S	16-Apr-2025	3:31:04 PM	5	1287.00	TQEX
GENMAB A/S	16-Apr-2025	3:31:04 PM	4	1287.00	TQEX
GENMAB A/S	16-Apr-2025	3:31:04 PM	21	1287.00	TQEX
GENMAB A/S	16-Apr-2025	3:31:04 PM	34	1288.00	AQEU
GENMAB A/S	16-Apr-2025	3:31:04 PM	4	1287.00	AQEU
GENMAB A/S	16-Apr-2025	3:31:04 PM	2	1287.00	AQEU
GENMAB A/S	16-Apr-2025	3:31:04 PM	2	1287.00	AQEU
GENMAB A/S	16-Apr-2025	3:31:04 PM	2	1287.00	AQEU
GENMAB A/S	16-Apr-2025	3:31:04 PM	5	1287.00	AQEU
GENMAB A/S	16-Apr-2025	3:31:04 PM	2	1287.00	AQEU
GENMAB A/S	16-Apr-2025	3:31:04 PM	14	1287.00	AQEU
GENMAB A/S	16-Apr-2025	3:31:04 PM	88	1288.00	CEUX
GENMAB A/S	16-Apr-2025	3:31:04 PM	36	1287.50	CEUX
GENMAB A/S	16-Apr-2025	3:31:04 PM	12	1287.00	CEUX
GENMAB A/S	16-Apr-2025	3:31:04 PM	5	1287.00	CEUX
GENMAB A/S	16-Apr-2025	3:31:04 PM	8	1287.00	CEUX
GENMAB A/S	16-Apr-2025	3:31:04 PM	22	1287.00	CEUX
GENMAB A/S	16-Apr-2025	3:31:04 PM	7	1287.00	CEUX
GENMAB A/S	16-Apr-2025	3:31:04 PM	3	1287.00	CEUX
GENMAB A/S	16-Apr-2025	3:31:04 PM	7	1287.00	CEUX
GENMAB A/S	16-Apr-2025	3:31:04 PM	5	1287.00	CEUX
GENMAB A/S	16-Apr-2025	3:31:04 PM	2	1287.00	CEUX
GENMAB A/S	16-Apr-2025	3:31:04 PM	5	1287.00	CEUX
GENMAB A/S	16-Apr-2025	3:31:04 PM	5	1287.00	CEUX
GENMAB A/S	16-Apr-2025	3:31:04 PM	5	1287.00	CEUX
GENMAB A/S	16-Apr-2025	3:31:04 PM	3	1287.00	CEUX
GENMAB A/S	16-Apr-2025	3:31:05 PM	28	1287.00	TQEX
GENMAB A/S	16-Apr-2025	3:31:05 PM	87	1287.00	CEUX
GENMAB A/S	16-Apr-2025	3:31:13 PM	22	1288.50	XCSE
GENMAB A/S	16-Apr-2025	3:31:45 PM	31	1288.00	AQEU
GENMAB A/S	16-Apr-2025	3:31:45 PM	34	1287.50	CEUX
GENMAB A/S	16-Apr-2025	3:31:45 PM	14	1288.50	CEUX
GENMAB A/S	16-Apr-2025	3:32:04 PM	34	1288.00	TQEX
GENMAB A/S	16-Apr-2025	3:32:04 PM	36	1288.50	CEUX
GENMAB A/S	16-Apr-2025	3:32:05 PM	15	1288.50	XCSE
GENMAB A/S	16-Apr-2025	3:32:05 PM	24	1288.50	XCSE
GENMAB A/S	16-Apr-2025	3:32:05 PM	37	1288.50	XCSE
GENMAB A/S	16-Apr-2025	3:32:07 PM	21	1288.50	XCSE
GENMAB A/S	16-Apr-2025	3:32:07 PM	37	1288.50	XCSE
GENMAB A/S	16-Apr-2025	3:32:07 PM	37	1288.50	XCSE

178

Exhibit 99.1(a)

APPENDIX Share buy-back programme - Specification for April 14 – April 18, 2025

GENMAB A/S	16-Apr-2025	3:32:08 PM	37	1288.50	XCSE
GENMAB A/S	16-Apr-2025	3:32:09 PM	14	1288.50	XCSE
GENMAB A/S	16-Apr-2025	3:32:09 PM	37	1288.50	XCSE
GENMAB A/S	16-Apr-2025	3:32:09 PM	38	1288.50	XCSE
GENMAB A/S	16-Apr-2025	3:32:11 PM	16	1288.50	XCSE
GENMAB A/S	16-Apr-2025	3:32:11 PM	37	1288.50	XCSE
GENMAB A/S	16-Apr-2025	3:32:11 PM	38	1288.50	XCSE
GENMAB A/S	16-Apr-2025	3:32:11 PM	16	1288.50	XCSE
GENMAB A/S	16-Apr-2025	3:32:11 PM	16	1288.50	XCSE
GENMAB A/S	16-Apr-2025	3:32:11 PM	17	1288.50	XCSE
GENMAB A/S	16-Apr-2025	3:32:11 PM	15	1288.50	XCSE
GENMAB A/S	16-Apr-2025	3:32:11 PM	15	1288.50	XCSE
GENMAB A/S	16-Apr-2025	3:32:11 PM	38	1288.50	XCSE
GENMAB A/S	16-Apr-2025	3:32:12 PM	30	1287.50	XCSE
GENMAB A/S	16-Apr-2025	3:32:12 PM	1	1287.50	XCSE
GENMAB A/S	16-Apr-2025	3:32:12 PM	30	1287.50	XCSE
GENMAB A/S	16-Apr-2025	3:32:12 PM	31	1287.50	XCSE
GENMAB A/S	16-Apr-2025	3:32:12 PM	15	1287.50	XCSE
GENMAB A/S	16-Apr-2025	3:32:12 PM	50	1287.50	XCSE
GENMAB A/S	16-Apr-2025	3:32:12 PM	15	1287.50	XCSE
GENMAB A/S	16-Apr-2025	3:32:12 PM	5	1287.50	XCSE
GENMAB A/S	16-Apr-2025	3:32:12 PM	15	1287.50	XCSE
GENMAB A/S	16-Apr-2025	3:32:12 PM	17	1287.50	XCSE
GENMAB A/S	16-Apr-2025	3:32:12 PM	2	1287.00	AQEU
GENMAB A/S	16-Apr-2025	3:32:12 PM	2	1287.00	AQEU
GENMAB A/S	16-Apr-2025	3:32:12 PM	8	1287.00	AQEU
GENMAB A/S	16-Apr-2025	3:32:12 PM	2	1287.00	AQEU
GENMAB A/S	16-Apr-2025	3:32:12 PM	37	1287.50	CEUX
GENMAB A/S	16-Apr-2025	3:32:12 PM	3	1287.50	CEUX
GENMAB A/S	16-Apr-2025	3:32:12 PM	12	1287.50	CEUX
GENMAB A/S	16-Apr-2025	3:32:13 PM	17	1286.50	CEUX
GENMAB A/S	16-Apr-2025	3:32:13 PM	9	1286.50	CEUX
GENMAB A/S	16-Apr-2025	3:32:13 PM	11	1286.50	CEUX
GENMAB A/S	16-Apr-2025	3:32:13 PM	14	1286.50	CEUX
GENMAB A/S	16-Apr-2025	3:32:25 PM	37	1286.50	CEUX
GENMAB A/S	16-Apr-2025	3:32:32 PM	4	1286.50	CEUX
GENMAB A/S	16-Apr-2025	3:32:32 PM	2	1286.50	CEUX
GENMAB A/S	16-Apr-2025	3:32:32 PM	2	1286.50	CEUX
GENMAB A/S	16-Apr-2025	3:32:32 PM	7	1286.50	CEUX
GENMAB A/S	16-Apr-2025	3:32:32 PM	2	1286.50	CEUX
GENMAB A/S	16-Apr-2025	3:32:32 PM	15	1287.50	CEUX
GENMAB A/S	16-Apr-2025	3:32:33 PM	2	1287.50	XCSE
GENMAB A/S	16-Apr-2025	3:32:43 PM	93	1287.00	XCSE

179

Exhibit 99.1(a)

APPENDIX Share buy-back programme - Specification for April 14 – April 18, 2025

GENMAB A/S	16-Apr-2025	3:32:43 PM	15	1287.00	CEUX
GENMAB A/S	16-Apr-2025	3:32:55 PM	74	1286.50	CEUX
GENMAB A/S	16-Apr-2025	3:33:01 PM	2	1288.50	TQEX
GENMAB A/S	16-Apr-2025	3:33:01 PM	4	1288.50	TQEX
GENMAB A/S	16-Apr-2025	3:33:01 PM	5	1288.50	TQEX
GENMAB A/S	16-Apr-2025	3:33:01 PM	85	1288.50	CEUX
GENMAB A/S	16-Apr-2025	3:33:01 PM	5	1288.50	CEUX
GENMAB A/S	16-Apr-2025	3:33:03 PM	35	1288.50	XCSE
GENMAB A/S	16-Apr-2025	3:33:03 PM	19	1288.50	TQEX
GENMAB A/S	16-Apr-2025	3:33:35 PM	67	1289.50	XCSE
GENMAB A/S	16-Apr-2025	3:33:35 PM	24	1289.50	XCSE
GENMAB A/S	16-Apr-2025	3:33:35 PM	5	1289.00	XCSE
GENMAB A/S	16-Apr-2025	3:33:35 PM	15	1289.00	XCSE
GENMAB A/S	16-Apr-2025	3:33:35 PM	15	1289.00	XCSE
GENMAB A/S	16-Apr-2025	3:33:35 PM	19	1289.00	XCSE
GENMAB A/S	16-Apr-2025	3:33:35 PM	13	1289.00	XCSE
GENMAB A/S	16-Apr-2025	3:33:35 PM	5	1289.00	XCSE
GENMAB A/S	16-Apr-2025	3:33:35 PM	17	1289.50	XCSE
GENMAB A/S	16-Apr-2025	3:33:35 PM	26	1289.50	TQEX
GENMAB A/S	16-Apr-2025	3:33:35 PM	3	1289.00	AQEU
GENMAB A/S	16-Apr-2025	3:33:35 PM	31	1289.00	AQEU
GENMAB A/S	16-Apr-2025	3:33:35 PM	89	1289.50	CEUX
GENMAB A/S	16-Apr-2025	3:33:35 PM	3	1289.50	CEUX
GENMAB A/S	16-Apr-2025	3:33:35 PM	7	1289.50	CEUX
GENMAB A/S	16-Apr-2025	3:33:35 PM	3	1289.50	CEUX
GENMAB A/S	16-Apr-2025	3:33:35 PM	2	1289.50	CEUX
GENMAB A/S	16-Apr-2025	3:33:36 PM	29	1290.00	XCSE
GENMAB A/S	16-Apr-2025	3:33:37 PM	90	1289.50	XCSE
GENMAB A/S	16-Apr-2025	3:33:37 PM	29	1290.00	XCSE
GENMAB A/S	16-Apr-2025	3:33:37 PM	37	1290.00	XCSE
GENMAB A/S	16-Apr-2025	3:33:37 PM	37	1290.00	XCSE
GENMAB A/S	16-Apr-2025	3:33:37 PM	14	1290.00	XCSE
GENMAB A/S	16-Apr-2025	3:33:37 PM	32	1289.50	TQEX
GENMAB A/S	16-Apr-2025	3:33:37 PM	31	1289.50	AQEU
GENMAB A/S	16-Apr-2025	3:33:37 PM	17	1289.50	CEUX
GENMAB A/S	16-Apr-2025	3:33:37 PM	6	1289.50	CEUX
GENMAB A/S	16-Apr-2025	3:33:37 PM	69	1289.50	CEUX
GENMAB A/S	16-Apr-2025	3:33:37 PM	36	1290.00	CEUX
GENMAB A/S	16-Apr-2025	3:33:38 PM	23	1290.00	XCSE
GENMAB A/S	16-Apr-2025	3:33:38 PM	15	1290.00	XCSE
GENMAB A/S	16-Apr-2025	3:33:38 PM	17	1290.00	XCSE
GENMAB A/S	16-Apr-2025	3:33:38 PM	37	1290.00	XCSE
GENMAB A/S	16-Apr-2025	3:33:39 PM	37	1290.00	XCSE

180

Exhibit 99.1(a)

APPENDIX Share buy-back programme - Specification for April 14 – April 18, 2025

GENMAB A/S	16-Apr-2025	3:33:39 PM	16	1290.00	XCSE
GENMAB A/S	16-Apr-2025	3:33:39 PM	1	1290.00	XCSE
GENMAB A/S	16-Apr-2025	3:33:39 PM	15	1290.00	XCSE
GENMAB A/S	16-Apr-2025	3:33:39 PM	14	1290.00	XCSE
GENMAB A/S	16-Apr-2025	3:33:39 PM	15	1290.00	XCSE
GENMAB A/S	16-Apr-2025	3:33:39 PM	15	1290.00	XCSE
GENMAB A/S	16-Apr-2025	3:33:39 PM	37	1290.00	XCSE
GENMAB A/S	16-Apr-2025	3:33:39 PM	37	1290.00	XCSE
GENMAB A/S	16-Apr-2025	3:33:39 PM	13	1290.00	XCSE
GENMAB A/S	16-Apr-2025	3:33:40 PM	15	1290.00	XCSE
GENMAB A/S	16-Apr-2025	3:33:40 PM	37	1290.00	XCSE
GENMAB A/S	16-Apr-2025	3:33:40 PM	14	1290.00	XCSE
GENMAB A/S	16-Apr-2025	3:33:40 PM	14	1290.00	XCSE
GENMAB A/S	16-Apr-2025	3:33:40 PM	37	1290.00	XCSE
GENMAB A/S	16-Apr-2025	3:33:40 PM	17	1290.00	XCSE
GENMAB A/S	16-Apr-2025	3:33:40 PM	37	1290.00	XCSE
GENMAB A/S	16-Apr-2025	3:33:40 PM	15	1290.00	XCSE
GENMAB A/S	16-Apr-2025	3:33:40 PM	17	1290.00	XCSE
GENMAB A/S	16-Apr-2025	3:33:40 PM	31	1290.00	XCSE
GENMAB A/S	16-Apr-2025	3:33:40 PM	35	1290.00	XCSE
GENMAB A/S	16-Apr-2025	3:33:43 PM	14	1290.00	XCSE
GENMAB A/S	16-Apr-2025	3:33:43 PM	14	1290.00	XCSE
GENMAB A/S	16-Apr-2025	3:33:43 PM	16	1290.00	XCSE
GENMAB A/S	16-Apr-2025	3:33:45 PM	35	1290.00	XCSE
GENMAB A/S	16-Apr-2025	3:33:45 PM	37	1290.00	XCSE
GENMAB A/S	16-Apr-2025	3:33:45 PM	37	1290.00	XCSE
GENMAB A/S	16-Apr-2025	3:33:45 PM	16	1290.00	XCSE
GENMAB A/S	16-Apr-2025	3:33:45 PM	16	1290.00	XCSE
GENMAB A/S	16-Apr-2025	3:33:45 PM	14	1290.00	XCSE
GENMAB A/S	16-Apr-2025	3:33:45 PM	37	1290.00	XCSE
GENMAB A/S	16-Apr-2025	3:33:46 PM	15	1290.00	XCSE
GENMAB A/S	16-Apr-2025	3:33:46 PM	37	1290.00	XCSE
GENMAB A/S	16-Apr-2025	3:33:46 PM	37	1290.00	XCSE
GENMAB A/S	16-Apr-2025	3:33:46 PM	28	1290.00	XCSE
GENMAB A/S	16-Apr-2025	3:33:46 PM	16	1290.00	XCSE
GENMAB A/S	16-Apr-2025	3:33:46 PM	15	1290.00	XCSE
GENMAB A/S	16-Apr-2025	3:33:46 PM	15	1290.00	XCSE
GENMAB A/S	16-Apr-2025	3:33:46 PM	37	1290.00	XCSE
GENMAB A/S	16-Apr-2025	3:33:48 PM	4	1289.50	CEUX
GENMAB A/S	16-Apr-2025	3:33:48 PM	15	1289.50	CEUX
GENMAB A/S	16-Apr-2025	3:33:48 PM	5	1289.50	CEUX
GENMAB A/S	16-Apr-2025	3:33:48 PM	20	1289.50	CEUX
GENMAB A/S	16-Apr-2025	3:33:50 PM	3	1288.50	CEUX

181

Exhibit 99.1(a)

APPENDIX Share buy-back programme - Specification for April 14 – April 18, 2025

GENMAB A/S	16-Apr-2025	3:33:50 PM	8	1288.50	CEUX
GENMAB A/S	16-Apr-2025	3:33:51 PM	41	1288.50	XCSE
GENMAB A/S	16-Apr-2025	3:33:51 PM	51	1288.50	XCSE
GENMAB A/S	16-Apr-2025	3:33:51 PM	14	1288.00	XCSE
GENMAB A/S	16-Apr-2025	3:33:51 PM	5	1288.00	XCSE
GENMAB A/S	16-Apr-2025	3:33:51 PM	22	1288.50	XCSE
GENMAB A/S	16-Apr-2025	3:33:51 PM	7	1288.50	XCSE
GENMAB A/S	16-Apr-2025	3:33:51 PM	8	1288.50	XCSE
GENMAB A/S	16-Apr-2025	3:33:51 PM	15	1288.50	XCSE
GENMAB A/S	16-Apr-2025	3:33:51 PM	46	1288.50	XCSE
GENMAB A/S	16-Apr-2025	3:33:51 PM	8	1288.00	AQEU
GENMAB A/S	16-Apr-2025	3:33:51 PM	18	1288.00	AQEU
GENMAB A/S	16-Apr-2025	3:33:51 PM	80	1288.50	CEUX
GENMAB A/S	16-Apr-2025	3:33:51 PM	15	1288.50	CEUX
GENMAB A/S	16-Apr-2025	3:33:51 PM	11	1287.50	CEUX
GENMAB A/S	16-Apr-2025	3:33:51 PM	17	1287.50	CEUX
GENMAB A/S	16-Apr-2025	3:33:51 PM	4	1287.50	CEUX
GENMAB A/S	16-Apr-2025	3:33:51 PM	40	1287.50	CEUX
GENMAB A/S	16-Apr-2025	3:34:26 PM	5	1291.00	AQEU
GENMAB A/S	16-Apr-2025	3:34:26 PM	5	1291.00	AQEU
GENMAB A/S	16-Apr-2025	3:34:26 PM	15	1291.00	AQEU
GENMAB A/S	16-Apr-2025	3:34:26 PM	42	1291.00	CEUX
GENMAB A/S	16-Apr-2025	3:34:26 PM	5	1291.00	CEUX
GENMAB A/S	16-Apr-2025	3:34:26 PM	15	1291.00	CEUX
GENMAB A/S	16-Apr-2025	3:34:26 PM	13	1291.00	CEUX
GENMAB A/S	16-Apr-2025	3:34:26 PM	5	1291.00	CEUX
GENMAB A/S	16-Apr-2025	3:34:26 PM	7	1291.00	CEUX
GENMAB A/S	16-Apr-2025	3:34:27 PM	7	1291.00	XCSE
GENMAB A/S	16-Apr-2025	3:34:27 PM	15	1291.00	XCSE
GENMAB A/S	16-Apr-2025	3:34:27 PM	4	1290.50	TQEX
GENMAB A/S	16-Apr-2025	3:34:27 PM	4	1290.50	TQEX
GENMAB A/S	16-Apr-2025	3:34:27 PM	50	1291.00	CEUX
GENMAB A/S	16-Apr-2025	3:34:27 PM	3	1291.00	CEUX
GENMAB A/S	16-Apr-2025	3:34:32 PM	17	1291.00	XCSE
GENMAB A/S	16-Apr-2025	3:34:32 PM	16	1291.00	XCSE
GENMAB A/S	16-Apr-2025	3:34:34 PM	89	1290.50	XCSE
GENMAB A/S	16-Apr-2025	3:34:34 PM	22	1290.50	TQEX
GENMAB A/S	16-Apr-2025	3:34:41 PM	36	1291.00	CEUX
GENMAB A/S	16-Apr-2025	3:34:45 PM	36	1291.00	CEUX
GENMAB A/S	16-Apr-2025	3:34:56 PM	76	1291.00	XCSE
GENMAB A/S	16-Apr-2025	3:34:56 PM	8	1291.00	XCSE
GENMAB A/S	16-Apr-2025	3:34:56 PM	4	1291.00	XCSE
GENMAB A/S	16-Apr-2025	3:34:56 PM	6	1291.00	CEUX

182

Exhibit 99.1(a)

APPENDIX Share buy-back programme - Specification for April 14 – April 18, 2025

GENMAB A/S	16-Apr-2025	3:34:56 PM	3	1291.00	CEUX
GENMAB A/S	16-Apr-2025	3:34:56 PM	71	1291.00	CEUX
GENMAB A/S	16-Apr-2025	3:34:56 PM	3	1291.00	CEUX
GENMAB A/S	16-Apr-2025	3:34:56 PM	6	1291.00	CEUX
GENMAB A/S	16-Apr-2025	3:35:00 PM	3	1291.00	CEUX
GENMAB A/S	16-Apr-2025	3:35:39 PM	93	1292.00	XCSE
GENMAB A/S	16-Apr-2025	3:35:39 PM	19	1291.00	XCSE
GENMAB A/S	16-Apr-2025	3:35:39 PM	25	1291.00	XCSE
GENMAB A/S	16-Apr-2025	3:35:39 PM	6	1291.00	XCSE
GENMAB A/S	16-Apr-2025	3:35:39 PM	5	1291.00	XCSE
GENMAB A/S	16-Apr-2025	3:35:39 PM	22	1291.00	XCSE
GENMAB A/S	16-Apr-2025	3:35:39 PM	15	1291.00	XCSE
GENMAB A/S	16-Apr-2025	3:35:39 PM	15	1291.50	XCSE
GENMAB A/S	16-Apr-2025	3:35:39 PM	10	1291.50	XCSE
GENMAB A/S	16-Apr-2025	3:35:39 PM	15	1291.50	TQEX
GENMAB A/S	16-Apr-2025	3:35:39 PM	2	1291.50	TQEX
GENMAB A/S	16-Apr-2025	3:35:39 PM	14	1291.50	TQEX
GENMAB A/S	16-Apr-2025	3:35:39 PM	5	1290.50	TQEX
GENMAB A/S	16-Apr-2025	3:35:39 PM	5	1290.50	TQEX
GENMAB A/S	16-Apr-2025	3:35:39 PM	11	1290.50	TQEX
GENMAB A/S	16-Apr-2025	3:35:39 PM	4	1290.50	TQEX
GENMAB A/S	16-Apr-2025	3:35:39 PM	1	1290.50	TQEX
GENMAB A/S	16-Apr-2025	3:35:39 PM	39	1292.00	AQEU
GENMAB A/S	16-Apr-2025	3:35:39 PM	36	1292.50	CEUX
GENMAB A/S	16-Apr-2025	3:35:39 PM	51	1292.00	CEUX
GENMAB A/S	16-Apr-2025	3:35:39 PM	42	1292.00	CEUX
GENMAB A/S	16-Apr-2025	3:35:39 PM	71	1291.00	CEUX
GENMAB A/S	16-Apr-2025	3:35:39 PM	20	1291.00	CEUX
GENMAB A/S	16-Apr-2025	3:36:28 PM	69	1293.00	CEUX
GENMAB A/S	16-Apr-2025	3:36:32 PM	20	1293.00	CEUX
GENMAB A/S	16-Apr-2025	3:36:34 PM	7	1292.50	AQEU
GENMAB A/S	16-Apr-2025	3:36:34 PM	6	1292.50	AQEU
GENMAB A/S	16-Apr-2025	3:36:36 PM	87	1292.50	XCSE
GENMAB A/S	16-Apr-2025	3:36:36 PM	17	1292.50	XCSE
GENMAB A/S	16-Apr-2025	3:36:36 PM	14	1292.50	XCSE
GENMAB A/S	16-Apr-2025	3:36:36 PM	25	1292.50	XCSE
GENMAB A/S	16-Apr-2025	3:36:36 PM	3	1292.50	XCSE
GENMAB A/S	16-Apr-2025	3:36:36 PM	12	1292.50	XCSE
GENMAB A/S	16-Apr-2025	3:36:36 PM	5	1292.50	XCSE
GENMAB A/S	16-Apr-2025	3:36:36 PM	11	1292.50	XCSE
GENMAB A/S	16-Apr-2025	3:36:36 PM	9	1292.50	XCSE
GENMAB A/S	16-Apr-2025	3:36:36 PM	4	1292.50	XCSE
GENMAB A/S	16-Apr-2025	3:36:36 PM	13	1292.50	XCSE

183

Exhibit 99.1(a)

APPENDIX Share buy-back programme - Specification for April 14 – April 18, 2025

GENMAB A/S	16-Apr-2025	3:36:36 PM	4	1293.00	XCSE
GENMAB A/S	16-Apr-2025	3:36:36 PM	30	1292.50	TQEX
GENMAB A/S	16-Apr-2025	3:36:37 PM	32	1292.50	XCSE
GENMAB A/S	16-Apr-2025	3:36:37 PM	33	1293.00	XCSE
GENMAB A/S	16-Apr-2025	3:36:37 PM	17	1293.00	XCSE
GENMAB A/S	16-Apr-2025	3:36:37 PM	17	1293.00	XCSE
GENMAB A/S	16-Apr-2025	3:36:37 PM	14	1293.00	XCSE
GENMAB A/S	16-Apr-2025	3:36:37 PM	16	1293.00	XCSE
GENMAB A/S	16-Apr-2025	3:36:37 PM	16	1293.00	XCSE
GENMAB A/S	16-Apr-2025	3:36:37 PM	37	1293.00	XCSE
GENMAB A/S	16-Apr-2025	3:36:37 PM	16	1293.00	XCSE
GENMAB A/S	16-Apr-2025	3:36:37 PM	27	1293.00	XCSE
GENMAB A/S	16-Apr-2025	3:36:53 PM	90	1292.50	XCSE
GENMAB A/S	16-Apr-2025	3:36:53 PM	10	1292.50	XCSE
GENMAB A/S	16-Apr-2025	3:36:53 PM	37	1293.00	XCSE
GENMAB A/S	16-Apr-2025	3:36:53 PM	14	1293.00	XCSE
GENMAB A/S	16-Apr-2025	3:36:53 PM	15	1293.00	XCSE
GENMAB A/S	16-Apr-2025	3:36:53 PM	15	1293.00	XCSE
GENMAB A/S	16-Apr-2025	3:36:53 PM	26	1293.00	XCSE
GENMAB A/S	16-Apr-2025	3:36:53 PM	37	1293.00	XCSE
GENMAB A/S	16-Apr-2025	3:36:53 PM	80	1293.00	XCSE
GENMAB A/S	16-Apr-2025	3:36:53 PM	82	1292.00	CEUX
GENMAB A/S	16-Apr-2025	3:36:54 PM	54	1293.00	XCSE
GENMAB A/S	16-Apr-2025	3:36:56 PM	1	1293.00	XCSE
GENMAB A/S	16-Apr-2025	3:36:58 PM	92	1292.50	XCSE
GENMAB A/S	16-Apr-2025	3:37:05 PM	3	1292.50	XCSE
GENMAB A/S	16-Apr-2025	3:37:05 PM	2	1292.50	XCSE
GENMAB A/S	16-Apr-2025	3:37:05 PM	7	1292.50	XCSE
GENMAB A/S	16-Apr-2025	3:37:05 PM	6	1292.00	CEUX
GENMAB A/S	16-Apr-2025	3:37:12 PM	87	1292.50	XCSE
GENMAB A/S	16-Apr-2025	3:37:12 PM	26	1293.00	AQEU
GENMAB A/S	16-Apr-2025	3:37:12 PM	90	1293.00	CEUX
GENMAB A/S	16-Apr-2025	3:37:27 PM	19	1292.00	CEUX
GENMAB A/S	16-Apr-2025	3:37:27 PM	70	1292.00	CEUX
GENMAB A/S	16-Apr-2025	3:38:12 PM	6	1294.00	CEUX
GENMAB A/S	16-Apr-2025	3:38:12 PM	3	1294.00	CEUX
GENMAB A/S	16-Apr-2025	3:38:12 PM	3	1294.00	CEUX
GENMAB A/S	16-Apr-2025	3:38:12 PM	5	1294.00	CEUX
GENMAB A/S	16-Apr-2025	3:38:14 PM	17	1293.50	XCSE
GENMAB A/S	16-Apr-2025	3:38:14 PM	3	1294.00	XCSE
GENMAB A/S	16-Apr-2025	3:38:14 PM	12	1294.00	XCSE
GENMAB A/S	16-Apr-2025	3:38:14 PM	2	1293.50	XCSE
GENMAB A/S	16-Apr-2025	3:38:14 PM	2	1293.50	XCSE

184

Exhibit 99.1(a)

APPENDIX Share buy-back programme - Specification for April 14 – April 18, 2025

GENMAB A/S	16-Apr-2025	3:38:14 PM	2	1293.50	XCSE
GENMAB A/S	16-Apr-2025	3:38:14 PM	5	1293.50	XCSE
GENMAB A/S	16-Apr-2025	3:38:14 PM	27	1294.00	AQEU
GENMAB A/S	16-Apr-2025	3:38:14 PM	73	1294.00	CEUX
GENMAB A/S	16-Apr-2025	3:38:29 PM	89	1293.50	XCSE
GENMAB A/S	16-Apr-2025	3:38:29 PM	35	1293.50	XCSE
GENMAB A/S	16-Apr-2025	3:38:29 PM	90	1293.50	CEUX
GENMAB A/S	16-Apr-2025	3:38:30 PM	26	1293.50	AQEU
GENMAB A/S	16-Apr-2025	3:39:01 PM	86	1293.50	XCSE
GENMAB A/S	16-Apr-2025	3:39:01 PM	46	1293.50	CEUX
GENMAB A/S	16-Apr-2025	3:39:01 PM	42	1293.50	CEUX
GENMAB A/S	16-Apr-2025	3:39:02 PM	37	1293.50	XCSE
GENMAB A/S	16-Apr-2025	3:39:02 PM	19	1293.50	XCSE
GENMAB A/S	16-Apr-2025	3:39:02 PM	14	1293.50	XCSE
GENMAB A/S	16-Apr-2025	3:39:02 PM	17	1293.50	XCSE
GENMAB A/S	16-Apr-2025	3:39:02 PM	30	1293.50	XCSE
GENMAB A/S	16-Apr-2025	3:39:02 PM	14	1293.00	TQEX
GENMAB A/S	16-Apr-2025	3:39:02 PM	12	1293.00	TQEX
GENMAB A/S	16-Apr-2025	3:39:07 PM	89	1292.50	XCSE
GENMAB A/S	16-Apr-2025	3:39:07 PM	37	1293.00	XCSE
GENMAB A/S	16-Apr-2025	3:39:07 PM	20	1293.00	XCSE
GENMAB A/S	16-Apr-2025	3:39:07 PM	15	1293.00	XCSE
GENMAB A/S	16-Apr-2025	3:39:07 PM	15	1293.00	XCSE
GENMAB A/S	16-Apr-2025	3:39:07 PM	17	1293.00	XCSE
GENMAB A/S	16-Apr-2025	3:39:07 PM	86	1292.50	CEUX
GENMAB A/S	16-Apr-2025	3:39:08 PM	17	1293.00	XCSE
GENMAB A/S	16-Apr-2025	3:39:08 PM	17	1293.00	XCSE
GENMAB A/S	16-Apr-2025	3:39:08 PM	5	1293.00	XCSE
GENMAB A/S	16-Apr-2025	3:39:08 PM	14	1293.00	XCSE
GENMAB A/S	16-Apr-2025	3:39:19 PM	37	1293.00	XCSE
GENMAB A/S	16-Apr-2025	3:39:19 PM	14	1293.00	XCSE
GENMAB A/S	16-Apr-2025	3:39:19 PM	17	1293.00	XCSE
GENMAB A/S	16-Apr-2025	3:39:19 PM	17	1293.00	XCSE
GENMAB A/S	16-Apr-2025	3:39:19 PM	32	1293.00	XCSE
GENMAB A/S	16-Apr-2025	3:39:20 PM	14	1293.00	XCSE
GENMAB A/S	16-Apr-2025	3:39:20 PM	17	1293.00	XCSE
GENMAB A/S	16-Apr-2025	3:39:20 PM	15	1293.00	XCSE
GENMAB A/S	16-Apr-2025	3:39:20 PM	71	1293.00	XCSE
GENMAB A/S	16-Apr-2025	3:39:20 PM	59	1293.00	XCSE
GENMAB A/S	16-Apr-2025	3:39:20 PM	16	1293.00	XCSE
GENMAB A/S	16-Apr-2025	3:39:20 PM	37	1293.00	XCSE
GENMAB A/S	16-Apr-2025	3:39:20 PM	5	1293.00	XCSE
GENMAB A/S	16-Apr-2025	3:39:21 PM	9	1293.00	XCSE

185

Exhibit 99.1(a)

APPENDIX Share buy-back programme - Specification for April 14 – April 18, 2025

GENMAB A/S	16-Apr-2025	3:39:21 PM	16	1293.00	XCSE
GENMAB A/S	16-Apr-2025	3:39:21 PM	16	1293.00	XCSE
GENMAB A/S	16-Apr-2025	3:39:21 PM	37	1293.00	XCSE
GENMAB A/S	16-Apr-2025	3:39:21 PM	17	1293.00	XCSE
GENMAB A/S	16-Apr-2025	3:39:21 PM	37	1293.00	XCSE
GENMAB A/S	16-Apr-2025	3:39:21 PM	14	1293.00	XCSE
GENMAB A/S	16-Apr-2025	3:39:21 PM	14	1293.00	XCSE
GENMAB A/S	16-Apr-2025	3:39:21 PM	35	1293.00	XCSE
GENMAB A/S	16-Apr-2025	3:39:21 PM	14	1293.00	XCSE
GENMAB A/S	16-Apr-2025	3:39:21 PM	15	1293.00	XCSE
GENMAB A/S	16-Apr-2025	3:39:21 PM	17	1293.00	XCSE
GENMAB A/S	16-Apr-2025	3:39:23 PM	15	1293.00	XCSE
GENMAB A/S	16-Apr-2025	3:39:23 PM	30	1293.00	XCSE
GENMAB A/S	16-Apr-2025	3:39:23 PM	37	1293.00	XCSE
GENMAB A/S	16-Apr-2025	3:39:23 PM	14	1293.00	XCSE
GENMAB A/S	16-Apr-2025	3:39:23 PM	16	1293.00	XCSE
GENMAB A/S	16-Apr-2025	3:39:23 PM	16	1293.00	XCSE
GENMAB A/S	16-Apr-2025	3:39:23 PM	8	1293.00	XCSE
GENMAB A/S	16-Apr-2025	3:39:24 PM	14	1293.00	XCSE
GENMAB A/S	16-Apr-2025	3:39:24 PM	37	1293.00	XCSE
GENMAB A/S	16-Apr-2025	3:39:24 PM	37	1293.00	XCSE
GENMAB A/S	16-Apr-2025	3:39:24 PM	29	1293.00	XCSE
GENMAB A/S	16-Apr-2025	3:39:25 PM	17	1293.00	XCSE
GENMAB A/S	16-Apr-2025	3:39:25 PM	37	1293.00	XCSE
GENMAB A/S	16-Apr-2025	3:39:25 PM	11	1293.00	XCSE
GENMAB A/S	16-Apr-2025	3:39:25 PM	31	1292.00	TQEX
GENMAB A/S	16-Apr-2025	3:40:03 PM	88	1291.50	XCSE
GENMAB A/S	16-Apr-2025	3:40:03 PM	1	1291.50	XCSE
GENMAB A/S	16-Apr-2025	3:40:15 PM	92	1290.50	XCSE
GENMAB A/S	16-Apr-2025	3:40:15 PM	10	1290.50	XCSE
GENMAB A/S	16-Apr-2025	3:40:15 PM	13	1290.50	XCSE
GENMAB A/S	16-Apr-2025	3:40:15 PM	17	1291.00	XCSE
GENMAB A/S	16-Apr-2025	3:40:15 PM	15	1291.00	XCSE
GENMAB A/S	16-Apr-2025	3:40:15 PM	15	1291.00	XCSE
GENMAB A/S	16-Apr-2025	3:40:15 PM	2	1290.50	TQEX
GENMAB A/S	16-Apr-2025	3:40:15 PM	3	1290.50	TQEX
GENMAB A/S	16-Apr-2025	3:40:15 PM	7	1290.50	TQEX
GENMAB A/S	16-Apr-2025	3:40:15 PM	8	1290.50	TQEX
GENMAB A/S	16-Apr-2025	3:40:15 PM	2	1290.50	TQEX
GENMAB A/S	16-Apr-2025	3:40:15 PM	3	1290.50	TQEX
GENMAB A/S	16-Apr-2025	3:40:15 PM	2	1290.50	TQEX
GENMAB A/S	16-Apr-2025	3:40:15 PM	28	1291.00	AQEU
GENMAB A/S	16-Apr-2025	3:40:15 PM	88	1291.00	CEUX

186

Exhibit 99.1(a)

APPENDIX Share buy-back programme - Specification for April 14 – April 18, 2025

GENMAB A/S	16-Apr-2025	3:40:16 PM	86	1290.50	XCSE
GENMAB A/S	16-Apr-2025	3:40:22 PM	3	1290.50	XCSE
GENMAB A/S	16-Apr-2025	3:40:23 PM	26	1290.00	AQEU
GENMAB A/S	16-Apr-2025	3:40:23 PM	1	1290.00	CEUX
GENMAB A/S	16-Apr-2025	3:40:23 PM	87	1290.00	CEUX
GENMAB A/S	16-Apr-2025	3:40:55 PM	87	1289.00	XCSE
GENMAB A/S	16-Apr-2025	3:40:55 PM	37	1289.00	XCSE
GENMAB A/S	16-Apr-2025	3:40:55 PM	3	1289.00	XCSE
GENMAB A/S	16-Apr-2025	3:40:55 PM	6	1289.00	XCSE
GENMAB A/S	16-Apr-2025	3:40:55 PM	3	1289.00	XCSE
GENMAB A/S	16-Apr-2025	3:40:55 PM	2	1289.00	XCSE
GENMAB A/S	16-Apr-2025	3:40:55 PM	5	1289.00	XCSE
GENMAB A/S	16-Apr-2025	3:40:55 PM	2	1289.00	XCSE
GENMAB A/S	16-Apr-2025	3:40:55 PM	2	1289.00	XCSE
GENMAB A/S	16-Apr-2025	3:40:55 PM	5	1289.00	XCSE
GENMAB A/S	16-Apr-2025	3:40:55 PM	10	1289.00	XCSE
GENMAB A/S	16-Apr-2025	3:40:55 PM	12	1289.00	XCSE
GENMAB A/S	16-Apr-2025	3:40:55 PM	30	1289.50	XCSE
GENMAB A/S	16-Apr-2025	3:40:55 PM	26	1289.00	TQEX
GENMAB A/S	16-Apr-2025	3:40:55 PM	53	1289.00	CEUX
GENMAB A/S	16-Apr-2025	3:40:55 PM	32	1288.00	CEUX
GENMAB A/S	16-Apr-2025	3:40:55 PM	34	1288.00	CEUX
GENMAB A/S	16-Apr-2025	3:40:55 PM	20	1288.00	CEUX
GENMAB A/S	16-Apr-2025	3:40:57 PM	117	1289.50	XCSE
GENMAB A/S	16-Apr-2025	3:40:57 PM	28	1289.50	XCSE
GENMAB A/S	16-Apr-2025	3:41:02 PM	2	1289.50	XCSE
GENMAB A/S	16-Apr-2025	3:41:06 PM	4	1289.50	XCSE
GENMAB A/S	16-Apr-2025	3:41:06 PM	37	1289.50	XCSE
GENMAB A/S	16-Apr-2025	3:41:17 PM	2	1289.50	XCSE
GENMAB A/S	16-Apr-2025	3:42:08 PM	89	1291.00	XCSE
GENMAB A/S	16-Apr-2025	3:42:08 PM	50	1291.00	XCSE
GENMAB A/S	16-Apr-2025	3:42:08 PM	37	1291.00	XCSE
GENMAB A/S	16-Apr-2025	3:42:08 PM	32	1290.50	TQEX
GENMAB A/S	16-Apr-2025	3:42:08 PM	26	1290.50	AQEU
GENMAB A/S	16-Apr-2025	3:43:01 PM	37	1291.00	XCSE
GENMAB A/S	16-Apr-2025	3:43:01 PM	2	1290.50	XCSE
GENMAB A/S	16-Apr-2025	3:43:01 PM	37	1291.00	XCSE
GENMAB A/S	16-Apr-2025	3:43:01 PM	26	1291.00	XCSE
GENMAB A/S	16-Apr-2025	3:43:01 PM	70	1290.00	CEUX
GENMAB A/S	16-Apr-2025	3:43:02 PM	45	1291.00	XCSE
GENMAB A/S	16-Apr-2025	3:43:02 PM	37	1291.00	XCSE
GENMAB A/S	16-Apr-2025	3:43:02 PM	16	1291.00	XCSE
GENMAB A/S	16-Apr-2025	3:43:02 PM	16	1291.00	XCSE

187

Exhibit 99.1(a)

APPENDIX Share buy-back programme - Specification for April 14 – April 18, 2025

GENMAB A/S	16-Apr-2025	3:43:02 PM	45	1291.00	XCSE
GENMAB A/S	16-Apr-2025	3:43:02 PM	31	1290.50	TQEX
GENMAB A/S	16-Apr-2025	3:43:02 PM	3	1290.50	AQEU
GENMAB A/S	16-Apr-2025	3:43:15 PM	87	1290.00	XCSE
GENMAB A/S	16-Apr-2025	3:43:15 PM	37	1290.00	XCSE
GENMAB A/S	16-Apr-2025	3:43:15 PM	5	1290.00	XCSE
GENMAB A/S	16-Apr-2025	3:43:15 PM	2	1290.00	XCSE
GENMAB A/S	16-Apr-2025	3:43:15 PM	14	1290.00	XCSE
GENMAB A/S	16-Apr-2025	3:43:15 PM	8	1290.00	XCSE
GENMAB A/S	16-Apr-2025	3:43:15 PM	2	1290.00	XCSE
GENMAB A/S	16-Apr-2025	3:43:15 PM	4	1290.00	XCSE
GENMAB A/S	16-Apr-2025	3:43:15 PM	2	1290.00	XCSE
GENMAB A/S	16-Apr-2025	3:43:15 PM	2	1290.00	XCSE
GENMAB A/S	16-Apr-2025	3:43:15 PM	7	1290.00	XCSE
GENMAB A/S	16-Apr-2025	3:43:15 PM	6	1289.50	AQEU
GENMAB A/S	16-Apr-2025	3:43:15 PM	7	1289.50	AQEU
GENMAB A/S	16-Apr-2025	3:43:15 PM	3	1289.50	AQEU
GENMAB A/S	16-Apr-2025	3:43:15 PM	2	1289.50	AQEU
GENMAB A/S	16-Apr-2025	3:43:15 PM	2	1289.50	AQEU
GENMAB A/S	16-Apr-2025	3:43:15 PM	2	1289.50	AQEU
GENMAB A/S	16-Apr-2025	3:43:15 PM	11	1290.00	CEUX
GENMAB A/S	16-Apr-2025	3:43:16 PM	3	1289.50	AQEU
GENMAB A/S	16-Apr-2025	3:43:29 PM	4	1289.00	XCSE
GENMAB A/S	16-Apr-2025	3:43:29 PM	2	1289.00	XCSE
GENMAB A/S	16-Apr-2025	3:43:29 PM	25	1289.00	XCSE
GENMAB A/S	16-Apr-2025	3:43:29 PM	5	1289.00	XCSE
GENMAB A/S	16-Apr-2025	3:43:29 PM	2	1289.00	XCSE
GENMAB A/S	16-Apr-2025	3:43:29 PM	21	1289.50	XCSE
GENMAB A/S	16-Apr-2025	3:43:29 PM	8	1289.50	XCSE
GENMAB A/S	16-Apr-2025	3:43:29 PM	37	1289.50	XCSE
GENMAB A/S	16-Apr-2025	3:43:38 PM	60	1290.00	XCSE
GENMAB A/S	16-Apr-2025	3:43:38 PM	28	1290.00	XCSE
GENMAB A/S	16-Apr-2025	3:43:38 PM	2	1290.00	TQEX
GENMAB A/S	16-Apr-2025	3:43:38 PM	3	1290.00	TQEX
GENMAB A/S	16-Apr-2025	3:43:38 PM	2	1290.00	TQEX
GENMAB A/S	16-Apr-2025	3:43:38 PM	8	1290.00	CEUX
GENMAB A/S	16-Apr-2025	3:43:38 PM	16	1290.00	CEUX
GENMAB A/S	16-Apr-2025	3:43:38 PM	10	1290.00	CEUX
GENMAB A/S	16-Apr-2025	3:43:38 PM	4	1290.00	CEUX
GENMAB A/S	16-Apr-2025	3:43:38 PM	5	1290.00	CEUX
GENMAB A/S	16-Apr-2025	3:43:38 PM	25	1290.00	CEUX
GENMAB A/S	16-Apr-2025	3:43:38 PM	11	1290.00	CEUX
GENMAB A/S	16-Apr-2025	3:43:38 PM	4	1290.00	CEUX

188

Exhibit 99.1(a)

APPENDIX Share buy-back programme - Specification for April 14 – April 18, 2025

GENMAB A/S	16-Apr-2025	3:43:38 PM	7	1290.00	CEUX
GENMAB A/S	16-Apr-2025	3:43:50 PM	88	1290.50	XCSE
GENMAB A/S	16-Apr-2025	3:44:01 PM	60	1290.00	XCSE
GENMAB A/S	16-Apr-2025	3:44:01 PM	16	1290.00	XCSE
GENMAB A/S	16-Apr-2025	3:44:01 PM	3	1289.50	XCSE
GENMAB A/S	16-Apr-2025	3:44:01 PM	15	1289.50	XCSE
GENMAB A/S	16-Apr-2025	3:44:01 PM	15	1289.50	XCSE
GENMAB A/S	16-Apr-2025	3:44:01 PM	53	1289.50	XCSE
GENMAB A/S	16-Apr-2025	3:44:01 PM	88	1290.00	CEUX
GENMAB A/S	16-Apr-2025	3:44:35 PM	5	1289.50	XCSE
GENMAB A/S	16-Apr-2025	3:45:01 PM	26	1288.50	CEUX
GENMAB A/S	16-Apr-2025	3:45:11 PM	89	1288.50	XCSE
GENMAB A/S	16-Apr-2025	3:45:13 PM	20	1288.00	AQEU
GENMAB A/S	16-Apr-2025	3:45:17 PM	6	1288.50	XCSE
GENMAB A/S	16-Apr-2025	3:45:17 PM	3	1288.50	XCSE
GENMAB A/S	16-Apr-2025	3:45:17 PM	2	1288.50	XCSE
GENMAB A/S	16-Apr-2025	3:45:17 PM	5	1288.00	TQEX
GENMAB A/S	16-Apr-2025	3:45:17 PM	2	1288.00	TQEX
GENMAB A/S	16-Apr-2025	3:45:17 PM	4	1288.00	TQEX
GENMAB A/S	16-Apr-2025	3:45:18 PM	3	1288.00	TQEX
GENMAB A/S	16-Apr-2025	3:45:22 PM	10	1288.00	TQEX
GENMAB A/S	16-Apr-2025	3:45:23 PM	5	1288.00	TQEX
GENMAB A/S	16-Apr-2025	3:45:23 PM	2	1288.00	TQEX
GENMAB A/S	16-Apr-2025	3:45:28 PM	4	1288.00	TQEX
GENMAB A/S	16-Apr-2025	3:45:29 PM	3	1288.00	XCSE
GENMAB A/S	16-Apr-2025	3:45:29 PM	16	1288.00	AQEU
GENMAB A/S	16-Apr-2025	3:45:29 PM	3	1288.00	CEUX
GENMAB A/S	16-Apr-2025	3:45:33 PM	17	1288.00	XCSE
GENMAB A/S	16-Apr-2025	3:45:33 PM	2	1288.00	XCSE
GENMAB A/S	16-Apr-2025	3:45:33 PM	4	1288.00	CEUX
GENMAB A/S	16-Apr-2025	3:45:33 PM	8	1288.00	CEUX
GENMAB A/S	16-Apr-2025	3:45:33 PM	3	1288.00	CEUX
GENMAB A/S	16-Apr-2025	3:45:33 PM	4	1288.00	CEUX
GENMAB A/S	16-Apr-2025	3:45:33 PM	2	1287.50	CEUX
GENMAB A/S	16-Apr-2025	3:45:33 PM	10	1287.50	CEUX
GENMAB A/S	16-Apr-2025	3:45:33 PM	5	1287.50	CEUX
GENMAB A/S	16-Apr-2025	3:45:33 PM	5	1287.50	CEUX
GENMAB A/S	16-Apr-2025	3:45:33 PM	7	1287.50	CEUX
GENMAB A/S	16-Apr-2025	3:45:33 PM	13	1287.50	CEUX
GENMAB A/S	16-Apr-2025	3:46:15 PM	89	1288.00	XCSE
GENMAB A/S	16-Apr-2025	3:46:15 PM	32	1288.00	AQEU
GENMAB A/S	16-Apr-2025	3:46:15 PM	8	1287.50	CEUX
GENMAB A/S	16-Apr-2025	3:46:15 PM	7	1288.00	CEUX

189

Exhibit 99.1(a)

APPENDIX Share buy-back programme - Specification for April 14 – April 18, 2025

GENMAB A/S	16-Apr-2025	3:46:15 PM	6	1288.00	CEUX
GENMAB A/S	16-Apr-2025	3:46:15 PM	2	1288.00	CEUX
GENMAB A/S	16-Apr-2025	3:46:15 PM	4	1288.00	CEUX
GENMAB A/S	16-Apr-2025	3:46:49 PM	5	1287.50	XCSE
GENMAB A/S	16-Apr-2025	3:46:49 PM	4	1287.00	TQEX
GENMAB A/S	16-Apr-2025	3:46:49 PM	4	1287.00	TQEX
GENMAB A/S	16-Apr-2025	3:46:49 PM	68	1287.50	CEUX
GENMAB A/S	16-Apr-2025	3:46:49 PM	21	1287.50	CEUX
GENMAB A/S	16-Apr-2025	3:46:49 PM	2	1287.50	CEUX
GENMAB A/S	16-Apr-2025	3:46:49 PM	7	1287.50	CEUX
GENMAB A/S	16-Apr-2025	3:46:59 PM	87	1287.00	XCSE
GENMAB A/S	16-Apr-2025	3:46:59 PM	70	1287.50	XCSE
GENMAB A/S	16-Apr-2025	3:46:59 PM	37	1287.50	XCSE
GENMAB A/S	16-Apr-2025	3:46:59 PM	10	1287.50	XCSE
GENMAB A/S	16-Apr-2025	3:46:59 PM	30	1287.00	TQEX
GENMAB A/S	16-Apr-2025	3:46:59 PM	26	1287.00	AQEU
GENMAB A/S	16-Apr-2025	3:46:59 PM	36	1287.50	CEUX
GENMAB A/S	16-Apr-2025	3:47:00 PM	37	1287.50	XCSE
GENMAB A/S	16-Apr-2025	3:47:00 PM	19	1287.50	XCSE
GENMAB A/S	16-Apr-2025	3:47:00 PM	100	1287.50	XCSE
GENMAB A/S	16-Apr-2025	3:47:00 PM	11	1287.50	XCSE
GENMAB A/S	16-Apr-2025	3:47:08 PM	37	1287.00	XCSE
GENMAB A/S	16-Apr-2025	3:47:08 PM	5	1287.00	XCSE
GENMAB A/S	16-Apr-2025	3:47:08 PM	7	1287.00	CEUX
GENMAB A/S	16-Apr-2025	3:47:08 PM	8	1287.00	CEUX
GENMAB A/S	16-Apr-2025	3:47:08 PM	86	1286.50	CEUX
GENMAB A/S	16-Apr-2025	3:47:22 PM	26	1287.00	XCSE
GENMAB A/S	16-Apr-2025	3:47:22 PM	37	1287.00	XCSE
GENMAB A/S	16-Apr-2025	3:47:25 PM	37	1287.00	XCSE
GENMAB A/S	16-Apr-2025	3:47:25 PM	15	1287.00	XCSE
GENMAB A/S	16-Apr-2025	3:47:25 PM	16	1287.00	XCSE
GENMAB A/S	16-Apr-2025	3:47:25 PM	17	1287.00	XCSE
GENMAB A/S	16-Apr-2025	3:47:25 PM	80	1286.50	CEUX
GENMAB A/S	16-Apr-2025	3:47:25 PM	9	1286.50	CEUX
GENMAB A/S	16-Apr-2025	3:47:26 PM	37	1287.00	XCSE
GENMAB A/S	16-Apr-2025	3:47:26 PM	14	1287.00	XCSE
GENMAB A/S	16-Apr-2025	3:47:26 PM	28	1286.50	AQEU
GENMAB A/S	16-Apr-2025	3:47:28 PM	16	1287.00	XCSE
GENMAB A/S	16-Apr-2025	3:47:29 PM	17	1287.00	XCSE
GENMAB A/S	16-Apr-2025	3:47:29 PM	2	1287.00	XCSE
GENMAB A/S	16-Apr-2025	3:47:29 PM	17	1287.00	XCSE
GENMAB A/S	16-Apr-2025	3:47:30 PM	2	1287.00	XCSE
GENMAB A/S	16-Apr-2025	3:47:34 PM	15	1287.00	XCSE

190

Exhibit 99.1(a)

APPENDIX Share buy-back programme - Specification for April 14 – April 18, 2025

GENMAB A/S	16-Apr-2025	3:47:35 PM	15	1287.00	XCSE
GENMAB A/S	16-Apr-2025	3:47:35 PM	14	1287.00	XCSE
GENMAB A/S	16-Apr-2025	3:47:35 PM	14	1287.00	XCSE
GENMAB A/S	16-Apr-2025	3:47:35 PM	15	1287.00	XCSE
GENMAB A/S	16-Apr-2025	3:47:35 PM	16	1287.00	XCSE
GENMAB A/S	16-Apr-2025	3:47:35 PM	14	1287.00	XCSE
GENMAB A/S	16-Apr-2025	3:47:35 PM	49	1287.00	XCSE
GENMAB A/S	16-Apr-2025	3:47:35 PM	15	1287.00	XCSE
GENMAB A/S	16-Apr-2025	3:47:35 PM	17	1287.00	XCSE
GENMAB A/S	16-Apr-2025	3:47:35 PM	49	1287.00	XCSE
GENMAB A/S	16-Apr-2025	3:47:35 PM	16	1287.00	XCSE
GENMAB A/S	16-Apr-2025	3:47:42 PM	100	1287.00	XCSE
GENMAB A/S	16-Apr-2025	3:47:48 PM	72	1287.00	XCSE
GENMAB A/S	16-Apr-2025	3:47:48 PM	16	1287.00	XCSE
GENMAB A/S	16-Apr-2025	3:48:00 PM	23	1286.50	CEUX
GENMAB A/S	16-Apr-2025	3:48:25 PM	65	1286.50	CEUX
GENMAB A/S	16-Apr-2025	3:48:55 PM	2	1286.50	CEUX
GENMAB A/S	16-Apr-2025	3:49:50 PM	1	1286.00	XCSE
GENMAB A/S	16-Apr-2025	3:49:50 PM	88	1286.00	XCSE
GENMAB A/S	16-Apr-2025	3:49:50 PM	2	1286.00	XCSE
GENMAB A/S	16-Apr-2025	3:49:50 PM	3	1286.00	XCSE
GENMAB A/S	16-Apr-2025	3:49:50 PM	28	1286.00	TQEX
GENMAB A/S	16-Apr-2025	3:49:50 PM	4	1286.50	CEUX
GENMAB A/S	16-Apr-2025	3:49:50 PM	20	1286.50	CEUX
GENMAB A/S	16-Apr-2025	3:49:50 PM	2	1286.50	CEUX
GENMAB A/S	16-Apr-2025	3:49:50 PM	3	1286.50	CEUX
GENMAB A/S	16-Apr-2025	3:49:50 PM	9	1286.50	CEUX
GENMAB A/S	16-Apr-2025	3:49:50 PM	7	1286.50	CEUX
GENMAB A/S	16-Apr-2025	3:49:50 PM	4	1286.50	CEUX
GENMAB A/S	16-Apr-2025	3:50:07 PM	63	1286.00	XCSE
GENMAB A/S	16-Apr-2025	3:50:07 PM	54	1286.00	XCSE
GENMAB A/S	16-Apr-2025	3:50:07 PM	46	1286.00	XCSE
GENMAB A/S	16-Apr-2025	3:50:07 PM	6	1286.00	XCSE
GENMAB A/S	16-Apr-2025	3:50:07 PM	3	1286.00	XCSE
GENMAB A/S	16-Apr-2025	3:50:08 PM	8	1286.00	XCSE
GENMAB A/S	16-Apr-2025	3:50:08 PM	4	1286.00	XCSE
GENMAB A/S	16-Apr-2025	3:50:08 PM	7	1286.00	XCSE
GENMAB A/S	16-Apr-2025	3:50:08 PM	10	1286.00	XCSE
GENMAB A/S	16-Apr-2025	3:50:08 PM	4	1286.00	XCSE
GENMAB A/S	16-Apr-2025	3:50:08 PM	16	1286.00	XCSE
GENMAB A/S	16-Apr-2025	3:50:08 PM	2	1285.50	AQEU
GENMAB A/S	16-Apr-2025	3:50:08 PM	8	1285.50	AQEU
GENMAB A/S	16-Apr-2025	3:50:08 PM	4	1286.00	CEUX

191

Exhibit 99.1(a)

APPENDIX Share buy-back programme - Specification for April 14 – April 18, 2025

GENMAB A/S	16-Apr-2025	3:50:08 PM	3	1286.00	CEUX
GENMAB A/S	16-Apr-2025	3:50:08 PM	4	1286.00	CEUX
GENMAB A/S	16-Apr-2025	3:50:08 PM	6	1286.00	CEUX
GENMAB A/S	16-Apr-2025	3:50:08 PM	3	1286.00	CEUX
GENMAB A/S	16-Apr-2025	3:50:32 PM	13	1286.50	CEUX
GENMAB A/S	16-Apr-2025	3:50:32 PM	3	1286.50	CEUX
GENMAB A/S	16-Apr-2025	3:50:32 PM	22	1286.50	CEUX
GENMAB A/S	16-Apr-2025	3:50:47 PM	89	1287.50	XCSE
GENMAB A/S	16-Apr-2025	3:50:47 PM	19	1287.50	AQEU
GENMAB A/S	16-Apr-2025	3:50:50 PM	88	1286.50	XCSE
GENMAB A/S	16-Apr-2025	3:50:50 PM	4	1286.50	TQEX
GENMAB A/S	16-Apr-2025	3:50:50 PM	15	1286.50	TQEX
GENMAB A/S	16-Apr-2025	3:50:50 PM	7	1286.50	TQEX
GENMAB A/S	16-Apr-2025	3:50:50 PM	15	1287.50	AQEU
GENMAB A/S	16-Apr-2025	3:50:50 PM	16	1287.00	CEUX
GENMAB A/S	16-Apr-2025	3:50:50 PM	36	1287.50	CEUX
GENMAB A/S	16-Apr-2025	3:50:50 PM	4	1287.00	CEUX
GENMAB A/S	16-Apr-2025	3:50:50 PM	6	1287.00	CEUX
GENMAB A/S	16-Apr-2025	3:50:50 PM	63	1287.00	CEUX
GENMAB A/S	16-Apr-2025	3:51:03 PM	93	1287.00	XCSE
GENMAB A/S	16-Apr-2025	3:51:09 PM	7	1287.00	XCSE
GENMAB A/S	16-Apr-2025	3:51:09 PM	3	1286.50	TQEX
GENMAB A/S	16-Apr-2025	3:51:09 PM	4	1286.50	AQEU
GENMAB A/S	16-Apr-2025	3:51:09 PM	9	1286.50	AQEU
GENMAB A/S	16-Apr-2025	3:51:09 PM	4	1286.50	AQEU
GENMAB A/S	16-Apr-2025	3:51:09 PM	92	1287.00	CEUX
GENMAB A/S	16-Apr-2025	3:51:09 PM	4	1287.00	CEUX
GENMAB A/S	16-Apr-2025	3:51:09 PM	2	1287.00	CEUX
GENMAB A/S	16-Apr-2025	3:51:33 PM	2	1286.50	TQEX
GENMAB A/S	16-Apr-2025	3:51:35 PM	21	1286.50	TQEX
GENMAB A/S	16-Apr-2025	3:51:35 PM	17	1286.50	AQEU
GENMAB A/S	16-Apr-2025	3:51:39 PM	4	1286.50	TQEX
GENMAB A/S	16-Apr-2025	3:51:45 PM	36	1286.50	CEUX
GENMAB A/S	16-Apr-2025	3:51:45 PM	93	1286.00	CEUX
GENMAB A/S	16-Apr-2025	3:52:51 PM	5	1286.50	XCSE
GENMAB A/S	16-Apr-2025	3:52:51 PM	46	1286.50	XCSE
GENMAB A/S	16-Apr-2025	3:52:51 PM	15	1286.50	XCSE
GENMAB A/S	16-Apr-2025	3:52:51 PM	37	1286.50	XCSE
GENMAB A/S	16-Apr-2025	3:52:51 PM	4	1286.50	CEUX
GENMAB A/S	16-Apr-2025	3:52:51 PM	7	1286.00	CEUX
GENMAB A/S	16-Apr-2025	3:52:51 PM	2	1286.00	CEUX
GENMAB A/S	16-Apr-2025	3:52:51 PM	2	1286.00	CEUX
GENMAB A/S	16-Apr-2025	3:52:51 PM	3	1286.00	CEUX

192

Exhibit 99.1(a)

APPENDIX Share buy-back programme - Specification for April 14 – April 18, 2025

GENMAB A/S	16-Apr-2025	3:52:51 PM	6	1286.00	CEUX
GENMAB A/S	16-Apr-2025	3:52:51 PM	69	1286.00	CEUX
GENMAB A/S	16-Apr-2025	3:53:01 PM	46	1286.50	XCSE
GENMAB A/S	16-Apr-2025	3:53:01 PM	20	1286.50	XCSE
GENMAB A/S	16-Apr-2025	3:53:01 PM	37	1286.50	XCSE
GENMAB A/S	16-Apr-2025	3:53:02 PM	46	1286.50	XCSE
GENMAB A/S	16-Apr-2025	3:53:02 PM	11	1286.50	XCSE
GENMAB A/S	16-Apr-2025	3:53:02 PM	37	1286.50	XCSE
GENMAB A/S	16-Apr-2025	3:53:02 PM	36	1286.50	CEUX
GENMAB A/S	16-Apr-2025	3:53:02 PM	36	1286.50	CEUX
GENMAB A/S	16-Apr-2025	3:53:03 PM	46	1286.50	XCSE
GENMAB A/S	16-Apr-2025	3:53:03 PM	36	1286.50	CEUX
GENMAB A/S	16-Apr-2025	3:53:04 PM	40	1286.50	XCSE
GENMAB A/S	16-Apr-2025	3:53:04 PM	37	1286.50	XCSE
GENMAB A/S	16-Apr-2025	3:53:04 PM	40	1286.50	XCSE
GENMAB A/S	16-Apr-2025	3:53:04 PM	32	1286.50	CEUX
GENMAB A/S	16-Apr-2025	3:53:07 PM	95	1287.00	XCSE
GENMAB A/S	16-Apr-2025	3:53:07 PM	22	1287.00	XCSE
GENMAB A/S	16-Apr-2025	3:53:10 PM	17	1287.00	XCSE
GENMAB A/S	16-Apr-2025	3:53:25 PM	20	1286.50	XCSE
GENMAB A/S	16-Apr-2025	3:53:25 PM	72	1286.50	XCSE
GENMAB A/S	16-Apr-2025	3:53:25 PM	27	1287.00	XCSE
GENMAB A/S	16-Apr-2025	3:53:25 PM	46	1287.00	XCSE
GENMAB A/S	16-Apr-2025	3:53:25 PM	37	1287.00	XCSE
GENMAB A/S	16-Apr-2025	3:53:25 PM	55	1286.50	TQEX
GENMAB A/S	16-Apr-2025	3:53:25 PM	59	1286.50	CEUX
GENMAB A/S	16-Apr-2025	3:53:25 PM	29	1286.50	CEUX
GENMAB A/S	16-Apr-2025	3:54:10 PM	60	1286.00	XCSE
GENMAB A/S	16-Apr-2025	3:54:10 PM	28	1286.50	XCSE
GENMAB A/S	16-Apr-2025	3:54:10 PM	29	1286.50	XCSE
GENMAB A/S	16-Apr-2025	3:54:10 PM	31	1286.50	AQEU
GENMAB A/S	16-Apr-2025	3:54:10 PM	36	1287.00	CEUX
GENMAB A/S	16-Apr-2025	3:54:10 PM	1	1287.00	CEUX
GENMAB A/S	16-Apr-2025	3:54:10 PM	14	1286.00	CEUX
GENMAB A/S	16-Apr-2025	3:54:10 PM	75	1286.00	CEUX
GENMAB A/S	16-Apr-2025	3:54:11 PM	17	1286.50	XCSE
GENMAB A/S	16-Apr-2025	3:54:11 PM	13	1286.50	XCSE
GENMAB A/S	16-Apr-2025	3:54:11 PM	37	1286.50	XCSE
GENMAB A/S	16-Apr-2025	3:54:11 PM	42	1286.50	XCSE
GENMAB A/S	16-Apr-2025	3:54:11 PM	37	1286.50	XCSE
GENMAB A/S	16-Apr-2025	3:54:11 PM	16	1286.50	XCSE
GENMAB A/S	16-Apr-2025	3:54:11 PM	46	1286.50	XCSE
GENMAB A/S	16-Apr-2025	3:54:11 PM	18	1286.50	XCSE

193

Exhibit 99.1(a)

APPENDIX Share buy-back programme - Specification for April 14 – April 18, 2025

GENMAB A/S	16-Apr-2025	3:54:12 PM	10	1286.50	XCSE
GENMAB A/S	16-Apr-2025	3:54:12 PM	46	1286.50	XCSE
GENMAB A/S	16-Apr-2025	3:54:12 PM	37	1286.50	XCSE
GENMAB A/S	16-Apr-2025	3:54:12 PM	37	1286.50	XCSE
GENMAB A/S	16-Apr-2025	3:54:12 PM	46	1286.50	XCSE
GENMAB A/S	16-Apr-2025	3:54:12 PM	15	1286.50	XCSE
GENMAB A/S	16-Apr-2025	3:54:12 PM	19	1286.50	XCSE
GENMAB A/S	16-Apr-2025	3:54:12 PM	9	1286.50	XCSE
GENMAB A/S	16-Apr-2025	3:54:12 PM	17	1286.50	XCSE
GENMAB A/S	16-Apr-2025	3:54:12 PM	46	1286.50	XCSE
GENMAB A/S	16-Apr-2025	3:54:12 PM	37	1286.50	XCSE
GENMAB A/S	16-Apr-2025	3:54:12 PM	4	1285.50	XCSE
GENMAB A/S	16-Apr-2025	3:54:12 PM	87	1285.50	XCSE
GENMAB A/S	16-Apr-2025	3:54:13 PM	14	1285.50	AQEU
GENMAB A/S	16-Apr-2025	3:54:13 PM	7	1285.50	AQEU
GENMAB A/S	16-Apr-2025	3:54:35 PM	50	1285.00	CEUX
GENMAB A/S	16-Apr-2025	3:55:00 PM	87	1285.50	XCSE
GENMAB A/S	16-Apr-2025	3:55:00 PM	46	1285.50	XCSE
GENMAB A/S	16-Apr-2025	3:55:00 PM	5	1286.00	XCSE
GENMAB A/S	16-Apr-2025	3:55:00 PM	46	1286.00	XCSE
GENMAB A/S	16-Apr-2025	3:55:00 PM	10	1286.00	XCSE
GENMAB A/S	16-Apr-2025	3:55:00 PM	5	1286.00	XCSE
GENMAB A/S	16-Apr-2025	3:55:00 PM	5	1286.00	XCSE
GENMAB A/S	16-Apr-2025	3:55:00 PM	1	1284.50	XCSE
GENMAB A/S	16-Apr-2025	3:55:00 PM	2	1284.50	XCSE
GENMAB A/S	16-Apr-2025	3:55:00 PM	25	1284.50	XCSE
GENMAB A/S	16-Apr-2025	3:55:00 PM	4	1286.00	TQEX
GENMAB A/S	16-Apr-2025	3:55:00 PM	15	1286.00	TQEX
GENMAB A/S	16-Apr-2025	3:55:00 PM	10	1286.00	TQEX
GENMAB A/S	16-Apr-2025	3:55:00 PM	4	1286.00	TQEX
GENMAB A/S	16-Apr-2025	3:55:00 PM	3	1286.00	TQEX
GENMAB A/S	16-Apr-2025	3:55:00 PM	5	1286.00	TQEX
GENMAB A/S	16-Apr-2025	3:55:00 PM	13	1286.00	TQEX
GENMAB A/S	16-Apr-2025	3:55:00 PM	3	1285.00	TQEX
GENMAB A/S	16-Apr-2025	3:55:00 PM	24	1285.00	TQEX
GENMAB A/S	16-Apr-2025	3:55:00 PM	7	1285.50	AQEU
GENMAB A/S	16-Apr-2025	3:55:00 PM	7	1285.50	AQEU
GENMAB A/S	16-Apr-2025	3:55:00 PM	2	1285.50	AQEU
GENMAB A/S	16-Apr-2025	3:55:00 PM	14	1285.50	AQEU
GENMAB A/S	16-Apr-2025	3:55:00 PM	5	1284.50	AQEU
GENMAB A/S	16-Apr-2025	3:55:00 PM	6	1284.50	AQEU
GENMAB A/S	16-Apr-2025	3:55:00 PM	21	1286.00	CEUX
GENMAB A/S	16-Apr-2025	3:55:00 PM	69	1286.00	CEUX

194

Exhibit 99.1(a)

APPENDIX Share buy-back programme - Specification for April 14 – April 18, 2025

GENMAB A/S	16-Apr-2025	3:55:00 PM	4	1285.00	CEUX
GENMAB A/S	16-Apr-2025	3:55:00 PM	32	1285.00	CEUX
GENMAB A/S	16-Apr-2025	3:55:03 PM	33	1285.50	XCSE
GENMAB A/S	16-Apr-2025	3:55:03 PM	52	1285.50	XCSE
GENMAB A/S	16-Apr-2025	3:55:03 PM	1	1285.50	XCSE
GENMAB A/S	16-Apr-2025	3:55:03 PM	5	1285.50	XCSE
GENMAB A/S	16-Apr-2025	3:55:07 PM	46	1285.50	XCSE
GENMAB A/S	16-Apr-2025	3:55:07 PM	6	1285.50	XCSE
GENMAB A/S	16-Apr-2025	3:55:07 PM	3	1285.50	XCSE
GENMAB A/S	16-Apr-2025	3:55:07 PM	16	1285.50	XCSE
GENMAB A/S	16-Apr-2025	3:55:07 PM	16	1285.50	XCSE
GENMAB A/S	16-Apr-2025	3:55:07 PM	30	1285.50	XCSE
GENMAB A/S	16-Apr-2025	3:55:07 PM	26	1285.00	TQEX
GENMAB A/S	16-Apr-2025	3:55:07 PM	24	1285.00	CEUX
GENMAB A/S	16-Apr-2025	3:55:07 PM	5	1285.00	CEUX
GENMAB A/S	16-Apr-2025	3:55:07 PM	15	1285.00	CEUX
GENMAB A/S	16-Apr-2025	3:55:07 PM	5	1285.00	CEUX
GENMAB A/S	16-Apr-2025	3:55:07 PM	37	1285.00	CEUX
GENMAB A/S	16-Apr-2025	3:55:23 PM	47	1284.50	XCSE
GENMAB A/S	16-Apr-2025	3:55:23 PM	12	1284.50	XCSE
GENMAB A/S	16-Apr-2025	3:55:23 PM	4	1284.00	TQEX
GENMAB A/S	16-Apr-2025	3:55:23 PM	6	1284.00	TQEX
GENMAB A/S	16-Apr-2025	3:55:23 PM	2	1284.00	TQEX
GENMAB A/S	16-Apr-2025	3:55:23 PM	4	1284.00	TQEX
GENMAB A/S	16-Apr-2025	3:55:23 PM	7	1284.00	TQEX
GENMAB A/S	16-Apr-2025	3:55:23 PM	2	1284.00	TQEX
GENMAB A/S	16-Apr-2025	3:55:23 PM	2	1284.00	TQEX
GENMAB A/S	16-Apr-2025	3:55:23 PM	19	1284.50	AQEU
GENMAB A/S	16-Apr-2025	3:55:23 PM	3	1283.50	CEUX
GENMAB A/S	16-Apr-2025	3:55:23 PM	10	1283.50	CEUX
GENMAB A/S	16-Apr-2025	3:55:23 PM	3	1283.50	CEUX
GENMAB A/S	16-Apr-2025	3:55:23 PM	3	1283.50	CEUX
GENMAB A/S	16-Apr-2025	3:55:23 PM	4	1283.50	CEUX
GENMAB A/S	16-Apr-2025	3:55:23 PM	6	1283.50	CEUX
GENMAB A/S	16-Apr-2025	3:55:23 PM	5	1283.50	CEUX
GENMAB A/S	16-Apr-2025	3:55:23 PM	3	1283.50	CEUX
GENMAB A/S	16-Apr-2025	3:55:24 PM	91	1284.00	XCSE
GENMAB A/S	16-Apr-2025	3:55:24 PM	26	1284.00	AQEU
GENMAB A/S	16-Apr-2025	3:55:25 PM	14	1284.50	XCSE
GENMAB A/S	16-Apr-2025	3:55:33 PM	9	1284.50	XCSE
GENMAB A/S	16-Apr-2025	3:56:25 PM	46	1284.50	XCSE
GENMAB A/S	16-Apr-2025	3:56:25 PM	46	1283.50	CEUX
GENMAB A/S	16-Apr-2025	3:56:41 PM	15	1285.00	XCSE

195

Exhibit 99.1(a)

APPENDIX Share buy-back programme - Specification for April 14 – April 18, 2025

GENMAB A/S	16-Apr-2025	3:57:00 PM	87	1285.00	XCSE
GENMAB A/S	16-Apr-2025	3:57:25 PM	36	1286.00	CEUX
GENMAB A/S	16-Apr-2025	3:57:27 PM	14	1286.00	XCSE
GENMAB A/S	16-Apr-2025	3:57:54 PM	90	1285.50	XCSE
GENMAB A/S	16-Apr-2025	3:57:54 PM	53	1285.50	CEUX
GENMAB A/S	16-Apr-2025	3:57:54 PM	5	1285.50	CEUX
GENMAB A/S	16-Apr-2025	3:57:55 PM	2	1285.50	AQEU
GENMAB A/S	16-Apr-2025	3:57:55 PM	8	1285.50	AQEU
GENMAB A/S	16-Apr-2025	3:57:55 PM	2	1285.50	AQEU
GENMAB A/S	16-Apr-2025	3:57:55 PM	2	1285.50	AQEU
GENMAB A/S	16-Apr-2025	3:57:55 PM	3	1285.50	AQEU
GENMAB A/S	16-Apr-2025	3:57:55 PM	4	1285.50	AQEU
GENMAB A/S	16-Apr-2025	3:57:55 PM	12	1285.50	AQEU
GENMAB A/S	16-Apr-2025	3:57:55 PM	7	1285.50	CEUX
GENMAB A/S	16-Apr-2025	3:57:55 PM	6	1285.50	CEUX
GENMAB A/S	16-Apr-2025	3:57:55 PM	2	1285.50	CEUX
GENMAB A/S	16-Apr-2025	3:57:55 PM	2	1285.50	CEUX
GENMAB A/S	16-Apr-2025	3:57:55 PM	2	1285.50	CEUX
GENMAB A/S	16-Apr-2025	3:57:55 PM	10	1285.50	CEUX
GENMAB A/S	16-Apr-2025	3:57:55 PM	6	1285.50	CEUX
GENMAB A/S	16-Apr-2025	3:58:05 PM	92	1285.50	XCSE
GENMAB A/S	16-Apr-2025	3:58:21 PM	39	1285.50	XCSE
GENMAB A/S	16-Apr-2025	3:58:21 PM	35	1285.50	XCSE
GENMAB A/S	16-Apr-2025	3:58:21 PM	37	1285.50	XCSE
GENMAB A/S	16-Apr-2025	3:58:21 PM	37	1285.00	TQEX
GENMAB A/S	16-Apr-2025	3:58:34 PM	22	1285.50	XCSE
GENMAB A/S	16-Apr-2025	3:58:34 PM	37	1285.50	XCSE
GENMAB A/S	16-Apr-2025	3:58:34 PM	16	1285.50	XCSE
GENMAB A/S	16-Apr-2025	3:58:34 PM	14	1285.50	XCSE
GENMAB A/S	16-Apr-2025	3:58:34 PM	14	1285.50	XCSE
GENMAB A/S	16-Apr-2025	3:58:34 PM	87	1284.50	CEUX
GENMAB A/S	16-Apr-2025	3:58:55 PM	22	1285.00	XCSE
GENMAB A/S	16-Apr-2025	3:58:55 PM	66	1285.00	XCSE
GENMAB A/S	16-Apr-2025	3:58:55 PM	35	1285.00	TQEX
GENMAB A/S	16-Apr-2025	3:58:55 PM	35	1285.00	AQEU
GENMAB A/S	16-Apr-2025	3:58:55 PM	87	1285.00	CEUX
GENMAB A/S	16-Apr-2025	3:59:35 PM	15	1284.00	XCSE
GENMAB A/S	16-Apr-2025	3:59:35 PM	74	1284.00	XCSE
GENMAB A/S	16-Apr-2025	3:59:35 PM	88	1283.00	XCSE
GENMAB A/S	16-Apr-2025	3:59:35 PM	4	1284.00	TQEX
GENMAB A/S	16-Apr-2025	3:59:35 PM	23	1284.00	TQEX
GENMAB A/S	16-Apr-2025	3:59:35 PM	28	1284.00	AQEU
GENMAB A/S	16-Apr-2025	3:59:35 PM	3	1283.50	CEUX

196

Exhibit 99.1(a)

APPENDIX Share buy-back programme - Specification for April 14 – April 18, 2025

GENMAB A/S	16-Apr-2025	3:59:35 PM	1	1282.50	CEUX
GENMAB A/S	16-Apr-2025	3:59:48 PM	18	1282.50	XCSE
GENMAB A/S	16-Apr-2025	3:59:48 PM	46	1282.50	TQEX
GENMAB A/S	16-Apr-2025	3:59:48 PM	90	1282.50	CEUX
GENMAB A/S	16-Apr-2025	3:59:48 PM	12	1282.50	CEUX
GENMAB A/S	16-Apr-2025	3:59:48 PM	3	1282.50	CEUX
GENMAB A/S	16-Apr-2025	3:59:58 PM	16	1282.50	XCSE
GENMAB A/S	16-Apr-2025	4:00:20 PM	26	1282.00	AQEU
GENMAB A/S	16-Apr-2025	4:00:26 PM	100	1282.00	XCSE
GENMAB A/S	16-Apr-2025	4:00:26 PM	45	1282.50	XCSE
GENMAB A/S	16-Apr-2025	4:00:26 PM	71	1282.50	XCSE
GENMAB A/S	16-Apr-2025	4:00:26 PM	1	1282.50	XCSE
GENMAB A/S	16-Apr-2025	4:00:27 PM	25	1282.50	XCSE
GENMAB A/S	16-Apr-2025	4:00:27 PM	30	1282.50	XCSE
GENMAB A/S	16-Apr-2025	4:00:27 PM	7	1282.50	XCSE
GENMAB A/S	16-Apr-2025	4:00:27 PM	4	1282.50	XCSE
GENMAB A/S	16-Apr-2025	4:00:27 PM	51	1282.50	XCSE
GENMAB A/S	16-Apr-2025	4:00:27 PM	88	1282.50	XCSE
GENMAB A/S	16-Apr-2025	4:00:34 PM	17	1282.50	XCSE
GENMAB A/S	16-Apr-2025	4:00:35 PM	18	1282.50	XCSE
GENMAB A/S	16-Apr-2025	4:00:36 PM	71	1281.50	CEUX
GENMAB A/S	16-Apr-2025	4:01:05 PM	7	1281.50	CEUX
GENMAB A/S	16-Apr-2025	4:01:19 PM	86	1281.50	XCSE
GENMAB A/S	16-Apr-2025	4:01:19 PM	9	1281.50	CEUX
GENMAB A/S	16-Apr-2025	4:01:27 PM	5	1281.50	XCSE
GENMAB A/S	16-Apr-2025	4:01:35 PM	88	1280.50	XCSE
GENMAB A/S	16-Apr-2025	4:01:35 PM	37	1281.50	XCSE
GENMAB A/S	16-Apr-2025	4:01:35 PM	66	1281.50	XCSE
GENMAB A/S	16-Apr-2025	4:01:35 PM	22	1281.50	XCSE
GENMAB A/S	16-Apr-2025	4:01:35 PM	16	1281.50	XCSE
GENMAB A/S	16-Apr-2025	4:01:35 PM	17	1281.50	XCSE
GENMAB A/S	16-Apr-2025	4:01:35 PM	14	1281.50	XCSE
GENMAB A/S	16-Apr-2025	4:01:35 PM	32	1281.50	XCSE
GENMAB A/S	16-Apr-2025	4:01:35 PM	16	1281.50	XCSE
GENMAB A/S	16-Apr-2025	4:01:36 PM	32	1281.50	XCSE
GENMAB A/S	16-Apr-2025	4:01:36 PM	14	1281.50	XCSE
GENMAB A/S	16-Apr-2025	4:01:36 PM	14	1281.50	XCSE
GENMAB A/S	16-Apr-2025	4:01:36 PM	17	1281.50	XCSE
GENMAB A/S	16-Apr-2025	4:01:36 PM	37	1281.50	XCSE
GENMAB A/S	16-Apr-2025	4:01:45 PM	88	1280.00	CEUX
GENMAB A/S	16-Apr-2025	4:02:00 PM	88	1279.50	XCSE
GENMAB A/S	16-Apr-2025	4:02:00 PM	36	1280.00	CEUX
GENMAB A/S	16-Apr-2025	4:02:00 PM	50	1280.00	CEUX

197

Exhibit 99.1(a)

APPENDIX Share buy-back programme - Specification for April 14 – April 18, 2025

GENMAB A/S	16-Apr-2025	4:02:01 PM	15	1279.50	AQEU
GENMAB A/S	16-Apr-2025	4:02:02 PM	39	1279.00	TQEX
GENMAB A/S	16-Apr-2025	4:02:02 PM	1	1279.00	TQEX
GENMAB A/S	16-Apr-2025	4:02:02 PM	16	1279.50	AQEU
GENMAB A/S	16-Apr-2025	4:02:02 PM	36	1279.50	CEUX
GENMAB A/S	16-Apr-2025	4:02:20 PM	7	1279.50	CEUX
GENMAB A/S	16-Apr-2025	4:02:35 PM	34	1280.00	CEUX
GENMAB A/S	16-Apr-2025	4:02:35 PM	59	1280.00	CEUX
GENMAB A/S	16-Apr-2025	4:02:43 PM	46	1280.50	XCSE
GENMAB A/S	16-Apr-2025	4:03:35 PM	89	1280.50	XCSE
GENMAB A/S	16-Apr-2025	4:03:35 PM	1	1280.00	CEUX
GENMAB A/S	16-Apr-2025	4:03:42 PM	3	1280.50	XCSE
GENMAB A/S	16-Apr-2025	4:03:43 PM	19	1281.00	CEUX
GENMAB A/S	16-Apr-2025	4:03:43 PM	24	1281.00	CEUX
GENMAB A/S	16-Apr-2025	4:03:53 PM	38	1282.00	CEUX
GENMAB A/S	16-Apr-2025	4:03:53 PM	2	1282.00	CEUX
GENMAB A/S	16-Apr-2025	4:03:54 PM	12	1282.00	TQEX
GENMAB A/S	16-Apr-2025	4:03:54 PM	25	1282.00	CEUX
GENMAB A/S	16-Apr-2025	4:03:54 PM	68	1282.00	CEUX
GENMAB A/S	16-Apr-2025	4:03:59 PM	24	1282.00	TQEX
GENMAB A/S	16-Apr-2025	4:04:06 PM	15	1282.50	CEUX
GENMAB A/S	16-Apr-2025	4:05:05 PM	46	1282.50	XCSE
GENMAB A/S	16-Apr-2025	4:05:05 PM	13	1282.50	XCSE
GENMAB A/S	16-Apr-2025	4:05:05 PM	8	1282.50	XCSE
GENMAB A/S	16-Apr-2025	4:05:05 PM	26	1282.50	XCSE
GENMAB A/S	16-Apr-2025	4:05:14 PM	87	1282.50	XCSE
GENMAB A/S	16-Apr-2025	4:05:14 PM	58	1282.50	CEUX
GENMAB A/S	16-Apr-2025	4:05:17 PM	35	1282.50	CEUX
GENMAB A/S	16-Apr-2025	4:06:35 PM	86	1284.00	XCSE
GENMAB A/S	16-Apr-2025	4:06:35 PM	40	1284.00	AQEU
GENMAB A/S	16-Apr-2025	4:06:35 PM	27	1284.50	CEUX
GENMAB A/S	16-Apr-2025	4:06:35 PM	1	1284.50	CEUX
GENMAB A/S	16-Apr-2025	4:07:16 PM	16	1285.00	TQEX
GENMAB A/S	16-Apr-2025	4:07:16 PM	2	1285.00	TQEX
GENMAB A/S	16-Apr-2025	4:07:19 PM	10	1285.00	TQEX
GENMAB A/S	16-Apr-2025	4:07:19 PM	4	1285.00	TQEX
GENMAB A/S	16-Apr-2025	4:07:35 PM	91	1284.50	XCSE
GENMAB A/S	16-Apr-2025	4:07:35 PM	55	1285.00	XCSE
GENMAB A/S	16-Apr-2025	4:07:35 PM	46	1285.00	XCSE
GENMAB A/S	16-Apr-2025	4:07:35 PM	15	1285.00	XCSE
GENMAB A/S	16-Apr-2025	4:07:35 PM	1	1285.00	XCSE
GENMAB A/S	16-Apr-2025	4:07:35 PM	25	1285.00	XCSE
GENMAB A/S	16-Apr-2025	4:07:35 PM	15	1285.00	XCSE

198

Exhibit 99.1(a)

APPENDIX Share buy-back programme - Specification for April 14 – April 18, 2025

GENMAB A/S	16-Apr-2025	4:07:35 PM	5	1285.00	XCSE
GENMAB A/S	16-Apr-2025	4:07:35 PM	91	1284.50	CEUX
GENMAB A/S	16-Apr-2025	4:07:39 PM	46	1285.00	XCSE
GENMAB A/S	16-Apr-2025	4:07:39 PM	24	1285.00	XCSE
GENMAB A/S	16-Apr-2025	4:07:44 PM	46	1285.00	XCSE
GENMAB A/S	16-Apr-2025	4:07:44 PM	3	1285.00	XCSE
GENMAB A/S	16-Apr-2025	4:07:44 PM	30	1284.50	AQEU
GENMAB A/S	16-Apr-2025	4:07:50 PM	46	1285.00	XCSE
GENMAB A/S	16-Apr-2025	4:07:52 PM	4	1284.50	AQEU
GENMAB A/S	16-Apr-2025	4:08:05 PM	35	1285.00	XCSE
GENMAB A/S	16-Apr-2025	4:08:05 PM	46	1285.00	XCSE
GENMAB A/S	16-Apr-2025	4:08:05 PM	6	1285.00	CEUX
GENMAB A/S	16-Apr-2025	4:08:05 PM	21	1285.00	CEUX
GENMAB A/S	16-Apr-2025	4:08:05 PM	4	1285.00	CEUX
GENMAB A/S	16-Apr-2025	4:08:05 PM	9	1285.00	CEUX
GENMAB A/S	16-Apr-2025	4:08:05 PM	36	1285.00	CEUX
GENMAB A/S	16-Apr-2025	4:08:09 PM	35	1285.00	XCSE
GENMAB A/S	16-Apr-2025	4:08:09 PM	46	1285.00	XCSE
GENMAB A/S	16-Apr-2025	4:08:09 PM	35	1285.00	XCSE
GENMAB A/S	16-Apr-2025	4:08:09 PM	46	1285.00	XCSE
GENMAB A/S	16-Apr-2025	4:08:09 PM	36	1285.00	CEUX
GENMAB A/S	16-Apr-2025	4:08:09 PM	36	1285.00	CEUX
GENMAB A/S	16-Apr-2025	4:08:10 PM	35	1285.00	XCSE
GENMAB A/S	16-Apr-2025	4:08:10 PM	35	1285.00	XCSE
GENMAB A/S	16-Apr-2025	4:08:10 PM	47	1285.00	XCSE
GENMAB A/S	16-Apr-2025	4:08:10 PM	15	1285.00	XCSE
GENMAB A/S	16-Apr-2025	4:08:10 PM	16	1285.00	XCSE
GENMAB A/S	16-Apr-2025	4:08:10 PM	4	1285.00	XCSE
GENMAB A/S	16-Apr-2025	4:08:10 PM	3	1284.50	AQEU
GENMAB A/S	16-Apr-2025	4:08:55 PM	90	1284.00	XCSE
GENMAB A/S	16-Apr-2025	4:08:55 PM	29	1284.00	TQEX
GENMAB A/S	16-Apr-2025	4:08:58 PM	100	1284.00	XCSE
GENMAB A/S	16-Apr-2025	4:08:58 PM	14	1284.00	XCSE
GENMAB A/S	16-Apr-2025	4:08:58 PM	16	1284.50	XCSE
GENMAB A/S	16-Apr-2025	4:08:58 PM	101	1284.50	XCSE
GENMAB A/S	16-Apr-2025	4:09:19 PM	37	1284.50	TQEX
GENMAB A/S	16-Apr-2025	4:09:19 PM	84	1284.50	CEUX
GENMAB A/S	16-Apr-2025	4:09:19 PM	7	1284.50	CEUX
GENMAB A/S	16-Apr-2025	4:10:01 PM	92	1285.00	XCSE
GENMAB A/S	16-Apr-2025	4:10:01 PM	34	1285.00	XCSE
GENMAB A/S	16-Apr-2025	4:10:01 PM	16	1285.00	XCSE
GENMAB A/S	16-Apr-2025	4:10:01 PM	36	1285.00	CEUX
GENMAB A/S	16-Apr-2025	4:10:01 PM	50	1285.00	CEUX

199

Exhibit 99.1(a)

APPENDIX Share buy-back programme - Specification for April 14 – April 18, 2025

GENMAB A/S	16-Apr-2025	4:10:06 PM	21	1284.50	AQEU
GENMAB A/S	16-Apr-2025	4:10:42 PM	2	1284.00	TQEX
GENMAB A/S	16-Apr-2025	4:10:42 PM	2	1284.00	TQEX
GENMAB A/S	16-Apr-2025	4:10:42 PM	2	1284.00	TQEX
GENMAB A/S	16-Apr-2025	4:10:42 PM	16	1284.50	AQEU
GENMAB A/S	16-Apr-2025	4:10:42 PM	4	1285.00	CEUX
GENMAB A/S	16-Apr-2025	4:10:42 PM	20	1285.00	CEUX
GENMAB A/S	16-Apr-2025	4:10:42 PM	8	1285.00	CEUX
GENMAB A/S	16-Apr-2025	4:10:43 PM	37	1284.00	CEUX
GENMAB A/S	16-Apr-2025	4:10:53 PM	2	1285.00	XCSE
GENMAB A/S	16-Apr-2025	4:10:53 PM	2	1285.00	XCSE
GENMAB A/S	16-Apr-2025	4:10:53 PM	85	1285.00	XCSE
GENMAB A/S	16-Apr-2025	4:10:54 PM	22	1285.00	CEUX
GENMAB A/S	16-Apr-2025	4:10:59 PM	36	1285.00	CEUX
GENMAB A/S	16-Apr-2025	4:11:16 PM	34	1285.00	XCSE
GENMAB A/S	16-Apr-2025	4:11:16 PM	22	1284.50	AQEU
GENMAB A/S	16-Apr-2025	4:11:16 PM	36	1285.00	CEUX
GENMAB A/S	16-Apr-2025	4:11:17 PM	18	1285.00	XCSE
GENMAB A/S	16-Apr-2025	4:11:27 PM	6	1284.50	AQEU
GENMAB A/S	16-Apr-2025	4:11:27 PM	36	1285.00	CEUX
GENMAB A/S	16-Apr-2025	4:11:27 PM	51	1285.00	CEUX
GENMAB A/S	16-Apr-2025	4:11:33 PM	12	1284.50	XCSE
GENMAB A/S	16-Apr-2025	4:11:33 PM	10	1284.50	XCSE
GENMAB A/S	16-Apr-2025	4:11:33 PM	46	1284.50	XCSE
GENMAB A/S	16-Apr-2025	4:11:33 PM	91	1284.00	XCSE
GENMAB A/S	16-Apr-2025	4:11:33 PM	2	1284.00	TQEX
GENMAB A/S	16-Apr-2025	4:11:33 PM	2	1284.00	TQEX
GENMAB A/S	16-Apr-2025	4:11:33 PM	10	1284.00	TQEX
GENMAB A/S	16-Apr-2025	4:11:33 PM	3	1284.00	TQEX
GENMAB A/S	16-Apr-2025	4:11:33 PM	11	1284.00	TQEX
GENMAB A/S	16-Apr-2025	4:11:33 PM	9	1284.50	CEUX
GENMAB A/S	16-Apr-2025	4:11:33 PM	7	1284.50	CEUX
GENMAB A/S	16-Apr-2025	4:11:33 PM	3	1284.50	CEUX
GENMAB A/S	16-Apr-2025	4:11:33 PM	4	1284.00	CEUX
GENMAB A/S	16-Apr-2025	4:11:33 PM	3	1284.00	CEUX
GENMAB A/S	16-Apr-2025	4:11:33 PM	5	1284.00	CEUX
GENMAB A/S	16-Apr-2025	4:11:33 PM	38	1284.00	CEUX
GENMAB A/S	16-Apr-2025	4:11:48 PM	15	1284.50	CEUX
GENMAB A/S	16-Apr-2025	4:11:51 PM	12	1284.50	CEUX
GENMAB A/S	16-Apr-2025	4:11:51 PM	12	1284.50	CEUX
GENMAB A/S	16-Apr-2025	4:13:06 PM	2	1284.00	XCSE
GENMAB A/S	16-Apr-2025	4:13:11 PM	39	1284.00	XCSE
GENMAB A/S	16-Apr-2025	4:13:11 PM	20	1284.00	XCSE

200

Exhibit 99.1(a)

APPENDIX Share buy-back programme - Specification for April 14 – April 18, 2025

GENMAB A/S	16-Apr-2025	4:13:11 PM	7	1284.00	XCSE
GENMAB A/S	16-Apr-2025	4:13:19 PM	46	1283.50	XCSE
GENMAB A/S	16-Apr-2025	4:13:19 PM	4	1283.50	XCSE
GENMAB A/S	16-Apr-2025	4:13:19 PM	5	1283.50	XCSE
GENMAB A/S	16-Apr-2025	4:13:19 PM	15	1283.50	XCSE
GENMAB A/S	16-Apr-2025	4:13:19 PM	15	1283.50	XCSE
GENMAB A/S	16-Apr-2025	4:13:19 PM	32	1284.00	XCSE
GENMAB A/S	16-Apr-2025	4:13:19 PM	10	1283.00	TQEX
GENMAB A/S	16-Apr-2025	4:13:19 PM	11	1283.50	AQEU
GENMAB A/S	16-Apr-2025	4:13:19 PM	25	1283.50	AQEU
GENMAB A/S	16-Apr-2025	4:13:19 PM	1	1283.50	AQEU
GENMAB A/S	16-Apr-2025	4:13:19 PM	93	1283.00	CEUX
GENMAB A/S	16-Apr-2025	4:13:20 PM	34	1283.50	XCSE
GENMAB A/S	16-Apr-2025	4:13:20 PM	16	1283.50	XCSE
GENMAB A/S	16-Apr-2025	4:13:20 PM	46	1283.50	XCSE
GENMAB A/S	16-Apr-2025	4:13:20 PM	18	1283.50	XCSE
GENMAB A/S	16-Apr-2025	4:13:20 PM	3	1284.00	XCSE
GENMAB A/S	16-Apr-2025	4:13:20 PM	17	1283.50	XCSE
GENMAB A/S	16-Apr-2025	4:13:20 PM	22	1283.50	XCSE
GENMAB A/S	16-Apr-2025	4:13:20 PM	46	1283.50	XCSE
GENMAB A/S	16-Apr-2025	4:13:20 PM	14	1283.50	XCSE
GENMAB A/S	16-Apr-2025	4:13:20 PM	15	1283.50	XCSE
GENMAB A/S	16-Apr-2025	4:13:20 PM	3	1284.00	XCSE
GENMAB A/S	16-Apr-2025	4:13:20 PM	10	1283.50	XCSE
GENMAB A/S	16-Apr-2025	4:13:20 PM	46	1283.50	XCSE
GENMAB A/S	16-Apr-2025	4:13:20 PM	8	1284.00	XCSE
GENMAB A/S	16-Apr-2025	4:13:20 PM	13	1284.00	XCSE
GENMAB A/S	16-Apr-2025	4:13:20 PM	37	1284.00	XCSE
GENMAB A/S	16-Apr-2025	4:13:20 PM	3	1284.00	XCSE
GENMAB A/S	16-Apr-2025	4:13:21 PM	14	1283.50	XCSE
GENMAB A/S	16-Apr-2025	4:13:21 PM	46	1283.50	XCSE
GENMAB A/S	16-Apr-2025	4:13:21 PM	18	1283.50	XCSE
GENMAB A/S	16-Apr-2025	4:13:21 PM	28	1284.00	XCSE
GENMAB A/S	16-Apr-2025	4:13:25 PM	14	1283.50	XCSE
GENMAB A/S	16-Apr-2025	4:13:25 PM	12	1283.50	XCSE
GENMAB A/S	16-Apr-2025	4:13:30 PM	36	1283.50	CEUX
GENMAB A/S	16-Apr-2025	4:13:30 PM	9	1283.50	CEUX
GENMAB A/S	16-Apr-2025	4:13:44 PM	93	1283.00	XCSE
GENMAB A/S	16-Apr-2025	4:13:44 PM	13	1283.00	TQEX
GENMAB A/S	16-Apr-2025	4:13:44 PM	4	1283.00	TQEX
GENMAB A/S	16-Apr-2025	4:13:45 PM	46	1283.50	XCSE
GENMAB A/S	16-Apr-2025	4:13:45 PM	35	1283.50	XCSE
GENMAB A/S	16-Apr-2025	4:13:45 PM	10	1283.50	XCSE

201

Exhibit 99.1(a)

APPENDIX Share buy-back programme - Specification for April 14 – April 18, 2025

GENMAB A/S	16-Apr-2025	4:13:45 PM	3	1283.50	XCSE
GENMAB A/S	16-Apr-2025	4:13:59 PM	3	1282.50	AQEU
GENMAB A/S	16-Apr-2025	4:14:25 PM	26	1284.50	AQEU
GENMAB A/S	16-Apr-2025	4:14:25 PM	36	1284.50	CEUX
GENMAB A/S	16-Apr-2025	4:14:25 PM	25	1284.50	CEUX
GENMAB A/S	16-Apr-2025	4:15:21 PM	31	1284.50	XCSE
GENMAB A/S	16-Apr-2025	4:15:21 PM	35	1284.50	XCSE
GENMAB A/S	16-Apr-2025	4:15:21 PM	3	1284.50	XCSE
GENMAB A/S	16-Apr-2025	4:15:21 PM	17	1284.50	XCSE
GENMAB A/S	16-Apr-2025	4:15:21 PM	34	1284.50	AQEU
GENMAB A/S	16-Apr-2025	4:15:21 PM	20	1284.50	CEUX
GENMAB A/S	16-Apr-2025	4:15:21 PM	13	1284.50	CEUX
GENMAB A/S	16-Apr-2025	4:15:35 PM	42	1284.00	CEUX
GENMAB A/S	16-Apr-2025	4:16:10 PM	87	1285.00	XCSE
GENMAB A/S	16-Apr-2025	4:16:10 PM	5	1284.00	TQEX
GENMAB A/S	16-Apr-2025	4:16:10 PM	4	1284.00	TQEX
GENMAB A/S	16-Apr-2025	4:16:10 PM	3	1284.00	TQEX
GENMAB A/S	16-Apr-2025	4:16:10 PM	2	1284.00	TQEX
GENMAB A/S	16-Apr-2025	4:16:10 PM	2	1284.00	TQEX
GENMAB A/S	16-Apr-2025	4:16:10 PM	7	1284.00	TQEX
GENMAB A/S	16-Apr-2025	4:16:10 PM	3	1284.00	TQEX
GENMAB A/S	16-Apr-2025	4:16:10 PM	36	1285.00	CEUX
GENMAB A/S	16-Apr-2025	4:16:10 PM	25	1285.00	CEUX
GENMAB A/S	16-Apr-2025	4:16:10 PM	50	1285.00	CEUX
GENMAB A/S	16-Apr-2025	4:16:10 PM	9	1284.00	CEUX
GENMAB A/S	16-Apr-2025	4:16:10 PM	42	1284.00	CEUX
GENMAB A/S	16-Apr-2025	4:16:12 PM	46	1284.50	XCSE
GENMAB A/S	16-Apr-2025	4:16:12 PM	15	1284.50	XCSE
GENMAB A/S	16-Apr-2025	4:16:17 PM	18	1284.50	CEUX
GENMAB A/S	16-Apr-2025	4:16:20 PM	92	1284.00	XCSE
GENMAB A/S	16-Apr-2025	4:16:20 PM	36	1284.50	CEUX
GENMAB A/S	16-Apr-2025	4:17:06 PM	89	1284.50	XCSE
GENMAB A/S	16-Apr-2025	4:17:19 PM	77	1284.50	CEUX
GENMAB A/S	16-Apr-2025	4:17:24 PM	34	1285.00	CEUX
GENMAB A/S	16-Apr-2025	4:17:24 PM	12	1285.00	CEUX
GENMAB A/S	16-Apr-2025	4:17:24 PM	20	1285.00	CEUX
GENMAB A/S	16-Apr-2025	4:17:24 PM	6	1285.00	CEUX
GENMAB A/S	16-Apr-2025	4:17:39 PM	36	1285.00	CEUX
GENMAB A/S	16-Apr-2025	4:18:05 PM	43	1285.50	XCSE
GENMAB A/S	16-Apr-2025	4:18:05 PM	45	1285.50	XCSE
GENMAB A/S	16-Apr-2025	4:18:05 PM	6	1285.50	XCSE
GENMAB A/S	16-Apr-2025	4:18:05 PM	2	1285.50	XCSE
GENMAB A/S	16-Apr-2025	4:18:05 PM	3	1285.50	XCSE

202

Exhibit 99.1(a)

APPENDIX Share buy-back programme - Specification for April 14 – April 18, 2025

GENMAB A/S	16-Apr-2025	4:18:05 PM	2	1285.50	XCSE
GENMAB A/S	16-Apr-2025	4:18:05 PM	2	1285.00	TQEX
GENMAB A/S	16-Apr-2025	4:18:05 PM	2	1285.00	TQEX
GENMAB A/S	16-Apr-2025	4:18:05 PM	2	1285.00	TQEX
GENMAB A/S	16-Apr-2025	4:18:05 PM	5	1285.00	TQEX
GENMAB A/S	16-Apr-2025	4:18:05 PM	26	1285.50	AQEU
GENMAB A/S	16-Apr-2025	4:18:05 PM	13	1285.50	AQEU
GENMAB A/S	16-Apr-2025	4:18:05 PM	88	1285.50	CEUX
GENMAB A/S	16-Apr-2025	4:18:05 PM	4	1285.50	CEUX
GENMAB A/S	16-Apr-2025	4:18:05 PM	5	1285.50	CEUX
GENMAB A/S	16-Apr-2025	4:18:35 PM	7	1285.50	XCSE
GENMAB A/S	16-Apr-2025	4:18:35 PM	9	1285.50	XCSE
GENMAB A/S	16-Apr-2025	4:18:35 PM	90	1285.50	XCSE
GENMAB A/S	16-Apr-2025	4:18:35 PM	4	1285.00	TQEX
GENMAB A/S	16-Apr-2025	4:18:35 PM	8	1285.00	TQEX
GENMAB A/S	16-Apr-2025	4:18:35 PM	2	1285.00	TQEX
GENMAB A/S	16-Apr-2025	4:18:35 PM	13	1285.00	TQEX
GENMAB A/S	16-Apr-2025	4:18:37 PM	35	1285.50	XCSE
GENMAB A/S	16-Apr-2025	4:18:37 PM	46	1285.50	XCSE
GENMAB A/S	16-Apr-2025	4:18:37 PM	36	1285.50	CEUX
GENMAB A/S	16-Apr-2025	4:18:38 PM	46	1285.50	XCSE
GENMAB A/S	16-Apr-2025	4:18:38 PM	23	1286.00	XCSE
GENMAB A/S	16-Apr-2025	4:18:38 PM	67	1286.00	XCSE
GENMAB A/S	16-Apr-2025	4:18:38 PM	23	1286.00	XCSE
GENMAB A/S	16-Apr-2025	4:18:38 PM	4	1286.00	XCSE
GENMAB A/S	16-Apr-2025	4:18:39 PM	31	1286.00	XCSE
GENMAB A/S	16-Apr-2025	4:18:39 PM	46	1286.00	XCSE
GENMAB A/S	16-Apr-2025	4:18:39 PM	18	1286.00	XCSE
GENMAB A/S	16-Apr-2025	4:18:49 PM	16	1286.00	CEUX
GENMAB A/S	16-Apr-2025	4:18:57 PM	17	1286.00	XCSE
GENMAB A/S	16-Apr-2025	4:19:04 PM	46	1286.00	XCSE
GENMAB A/S	16-Apr-2025	4:19:04 PM	36	1286.00	CEUX
GENMAB A/S	16-Apr-2025	4:19:25 PM	87	1285.50	XCSE
GENMAB A/S	16-Apr-2025	4:19:25 PM	46	1286.00	XCSE
GENMAB A/S	16-Apr-2025	4:19:25 PM	41	1286.00	XCSE
GENMAB A/S	16-Apr-2025	4:19:29 PM	17	1285.50	AQEU
GENMAB A/S	16-Apr-2025	4:19:59 PM	9	1285.50	AQEU
GENMAB A/S	16-Apr-2025	4:20:27 PM	93	1286.50	XCSE
GENMAB A/S	16-Apr-2025	4:21:00 PM	75	1287.00	XCSE
GENMAB A/S	16-Apr-2025	4:21:00 PM	13	1287.00	XCSE
GENMAB A/S	16-Apr-2025	4:21:23 PM	18	1287.00	TQEX
GENMAB A/S	16-Apr-2025	4:21:23 PM	38	1287.00	TQEX
GENMAB A/S	16-Apr-2025	4:21:29 PM	26	1287.00	TQEX

203

Exhibit 99.1(a)

APPENDIX Share buy-back programme - Specification for April 14 – April 18, 2025

GENMAB A/S	16-Apr-2025	4:21:35 PM	87	1287.00	XCSE
GENMAB A/S	16-Apr-2025	4:21:35 PM	31	1287.00	TQEX
GENMAB A/S	16-Apr-2025	4:21:45 PM	12	1287.00	XCSE
GENMAB A/S	16-Apr-2025	4:21:45 PM	79	1287.00	XCSE
GENMAB A/S	16-Apr-2025	4:22:05 PM	22	1287.00	XCSE
GENMAB A/S	16-Apr-2025	4:22:05 PM	18	1287.00	XCSE
GENMAB A/S	16-Apr-2025	4:22:05 PM	83	1286.50	CEUX
GENMAB A/S	16-Apr-2025	4:22:52 PM	25	1287.00	TQEX
GENMAB A/S	16-Apr-2025	4:22:52 PM	5	1287.00	TQEX
GENMAB A/S	16-Apr-2025	4:22:55 PM	80	1288.00	XCSE
GENMAB A/S	16-Apr-2025	4:23:08 PM	11	1288.00	XCSE
GENMAB A/S	16-Apr-2025	4:23:25 PM	88	1287.50	CEUX
GENMAB A/S	16-Apr-2025	4:23:25 PM	25	1287.50	CEUX
GENMAB A/S	16-Apr-2025	4:23:25 PM	54	1287.50	AQEU
GENMAB A/S	16-Apr-2025	4:24:15 PM	86	1287.00	XCSE
GENMAB A/S	16-Apr-2025	4:24:15 PM	46	1288.00	XCSE
GENMAB A/S	16-Apr-2025	4:24:15 PM	16	1288.00	XCSE
GENMAB A/S	16-Apr-2025	4:24:15 PM	2	1286.50	CEUX
GENMAB A/S	16-Apr-2025	4:24:15 PM	93	1287.50	CEUX
GENMAB A/S	16-Apr-2025	4:24:15 PM	42	1288.00	CEUX
GENMAB A/S	16-Apr-2025	4:24:15 PM	19	1288.00	CEUX
GENMAB A/S	16-Apr-2025	4:24:15 PM	33	1287.50	AQEU
GENMAB A/S	16-Apr-2025	4:24:58 PM	38	1288.00	AQEU
GENMAB A/S	16-Apr-2025	4:25:04 PM	33	1288.50	XCSE
GENMAB A/S	16-Apr-2025	4:25:04 PM	27	1288.50	XCSE
GENMAB A/S	16-Apr-2025	4:25:05 PM	35	1288.50	XCSE
GENMAB A/S	16-Apr-2025	4:25:05 PM	26	1288.50	XCSE
GENMAB A/S	16-Apr-2025	4:25:05 PM	46	1288.50	XCSE
GENMAB A/S	16-Apr-2025	4:25:06 PM	46	1288.50	XCSE
GENMAB A/S	16-Apr-2025	4:25:06 PM	20	1288.50	XCSE
GENMAB A/S	16-Apr-2025	4:25:06 PM	18	1288.50	XCSE
GENMAB A/S	16-Apr-2025	4:25:06 PM	15	1288.50	XCSE
GENMAB A/S	16-Apr-2025	4:25:08 PM	10	1288.50	XCSE
GENMAB A/S	16-Apr-2025	4:25:08 PM	46	1288.50	XCSE
GENMAB A/S	16-Apr-2025	4:25:55 PM	89	1287.50	XCSE
GENMAB A/S	16-Apr-2025	4:25:55 PM	93	1287.50	CEUX
GENMAB A/S	16-Apr-2025	4:26:19 PM	43	1287.50	XCSE
GENMAB A/S	16-Apr-2025	4:26:19 PM	36	1287.50	CEUX
GENMAB A/S	16-Apr-2025	4:26:19 PM	17	1287.50	CEUX
GENMAB A/S	16-Apr-2025	4:26:19 PM	16	1287.50	CEUX
GENMAB A/S	16-Apr-2025	4:26:19 PM	23	1287.50	CEUX
GENMAB A/S	16-Apr-2025	4:26:20 PM	26	1287.50	XCSE
GENMAB A/S	16-Apr-2025	4:26:20 PM	18	1287.50	XCSE

204

Exhibit 99.1(a)

APPENDIX Share buy-back programme - Specification for April 14 – April 18, 2025

GENMAB A/S	16-Apr-2025	4:26:20 PM	46	1287.50	XCSE
GENMAB A/S	16-Apr-2025	4:26:20 PM	36	1287.50	CEUX
GENMAB A/S	16-Apr-2025	4:26:23 PM	36	1287.50	CEUX
GENMAB A/S	16-Apr-2025	4:26:55 PM	46	1287.50	XCSE
GENMAB A/S	16-Apr-2025	4:26:55 PM	21	1287.50	XCSE
GENMAB A/S	16-Apr-2025	4:26:55 PM	15	1287.50	XCSE
GENMAB A/S	16-Apr-2025	4:26:55 PM	35	1287.50	XCSE
GENMAB A/S	16-Apr-2025	4:26:55 PM	7	1287.50	XCSE
GENMAB A/S	16-Apr-2025	4:26:55 PM	25	1287.50	XCSE
GENMAB A/S	16-Apr-2025	4:26:55 PM	46	1287.50	XCSE
GENMAB A/S	16-Apr-2025	4:26:55 PM	15	1287.50	XCSE
GENMAB A/S	16-Apr-2025	4:26:55 PM	16	1287.50	XCSE
GENMAB A/S	16-Apr-2025	4:26:55 PM	8	1287.50	XCSE
GENMAB A/S	16-Apr-2025	4:26:55 PM	34	1287.00	TQEX
GENMAB A/S	16-Apr-2025	4:26:56 PM	8	1287.50	XCSE
GENMAB A/S	16-Apr-2025	4:26:56 PM	17	1287.50	XCSE
GENMAB A/S	16-Apr-2025	4:26:56 PM	15	1287.50	XCSE
GENMAB A/S	16-Apr-2025	4:26:56 PM	46	1287.50	XCSE
GENMAB A/S	16-Apr-2025	4:26:56 PM	22	1287.50	XCSE
GENMAB A/S	16-Apr-2025	4:27:15 PM	91	1286.50	XCSE
GENMAB A/S	16-Apr-2025	4:27:15 PM	8	1286.50	CEUX
GENMAB A/S	16-Apr-2025	4:27:15 PM	17	1286.50	AQEU
GENMAB A/S	16-Apr-2025	4:27:15 PM	9	1286.50	AQEU
GENMAB A/S	16-Apr-2025	4:27:36 PM	31	1286.50	XCSE
GENMAB A/S	16-Apr-2025	4:27:36 PM	24	1286.50	XCSE
GENMAB A/S	16-Apr-2025	4:27:36 PM	9	1286.00	TQEX
GENMAB A/S	16-Apr-2025	4:27:36 PM	36	1286.50	CEUX
GENMAB A/S	16-Apr-2025	4:27:36 PM	52	1286.50	CEUX
GENMAB A/S	16-Apr-2025	4:27:42 PM	14	1286.50	CEUX
GENMAB A/S	16-Apr-2025	4:27:42 PM	18	1286.50	CEUX
GENMAB A/S	16-Apr-2025	4:27:55 PM	15	1286.50	CEUX
GENMAB A/S	16-Apr-2025	4:28:29 PM	24	1286.00	TQEX
GENMAB A/S	16-Apr-2025	4:28:52 PM	46	1286.50	XCSE
GENMAB A/S	16-Apr-2025	4:28:55 PM	5	1286.00	XCSE
GENMAB A/S	16-Apr-2025	4:28:55 PM	36	1286.00	CEUX
GENMAB A/S	16-Apr-2025	4:28:55 PM	86	1285.50	CEUX
GENMAB A/S	16-Apr-2025	4:28:56 PM	26	1285.50	AQEU
GENMAB A/S	16-Apr-2025	4:29:10 PM	30	1286.00	CEUX
GENMAB A/S	16-Apr-2025	4:29:49 PM	86	1285.50	XCSE
GENMAB A/S	16-Apr-2025	4:29:49 PM	8	1285.50	AQEU
GENMAB A/S	16-Apr-2025	4:30:15 PM	12	1285.00	TQEX
GENMAB A/S	16-Apr-2025	4:31:04 PM	88	1285.50	XCSE
GENMAB A/S	16-Apr-2025	4:31:04 PM	35	1286.00	XCSE

205

Exhibit 99.1(a)

APPENDIX Share buy-back programme - Specification for April 14 – April 18, 2025

GENMAB A/S	16-Apr-2025	4:31:04 PM	46	1286.00	XCSE
GENMAB A/S	16-Apr-2025	4:31:04 PM	45	1286.00	XCSE
GENMAB A/S	16-Apr-2025	4:31:04 PM	7	1286.00	XCSE
GENMAB A/S	16-Apr-2025	4:31:04 PM	35	1286.00	XCSE
GENMAB A/S	16-Apr-2025	4:31:04 PM	30	1286.00	XCSE
GENMAB A/S	16-Apr-2025	4:31:04 PM	89	1285.50	CEUX
GENMAB A/S	16-Apr-2025	4:31:04 PM	30	1285.50	CEUX
GENMAB A/S	16-Apr-2025	4:31:04 PM	36	1286.00	CEUX
GENMAB A/S	16-Apr-2025	4:31:04 PM	9	1286.00	CEUX
GENMAB A/S	16-Apr-2025	4:31:04 PM	9	1286.00	CEUX
GENMAB A/S	16-Apr-2025	4:31:05 PM	23	1286.00	XCSE
GENMAB A/S	16-Apr-2025	4:31:05 PM	46	1286.00	XCSE
GENMAB A/S	16-Apr-2025	4:31:25 PM	21	1286.00	XCSE
GENMAB A/S	16-Apr-2025	4:31:25 PM	7	1286.00	XCSE
GENMAB A/S	16-Apr-2025	4:32:02 PM	46	1288.50	CEUX
GENMAB A/S	16-Apr-2025	4:32:02 PM	40	1288.50	CEUX
GENMAB A/S	16-Apr-2025	4:32:02 PM	3	1288.00	CEUX
GENMAB A/S	16-Apr-2025	4:32:02 PM	45	1288.50	AQEU
GENMAB A/S	16-Apr-2025	4:32:15 PM	30	1288.50	CEUX
GENMAB A/S	16-Apr-2025	4:32:46 PM	40	1288.00	XCSE
GENMAB A/S	16-Apr-2025	4:32:46 PM	51	1288.00	XCSE
GENMAB A/S	16-Apr-2025	4:32:46 PM	52	1288.00	CEUX
GENMAB A/S	16-Apr-2025	4:32:46 PM	32	1288.00	CEUX
GENMAB A/S	16-Apr-2025	4:33:15 PM	48	1287.50	TQEX
GENMAB A/S	16-Apr-2025	4:33:15 PM	13	1287.50	TQEX
GENMAB A/S	16-Apr-2025	4:33:15 PM	34	1287.50	AQEU
GENMAB A/S	16-Apr-2025	4:33:16 PM	10	1287.50	AQEU
GENMAB A/S	16-Apr-2025	4:33:24 PM	39	1287.50	XCSE
GENMAB A/S	16-Apr-2025	4:33:24 PM	35	1287.50	XCSE
GENMAB A/S	16-Apr-2025	4:33:24 PM	13	1287.50	XCSE
GENMAB A/S	16-Apr-2025	4:33:24 PM	28	1287.50	XCSE
GENMAB A/S	16-Apr-2025	4:33:24 PM	36	1287.50	CEUX
GENMAB A/S	16-Apr-2025	4:33:24 PM	17	1287.50	CEUX
GENMAB A/S	16-Apr-2025	4:33:25 PM	46	1287.50	XCSE
GENMAB A/S	16-Apr-2025	4:33:25 PM	36	1287.50	CEUX
GENMAB A/S	16-Apr-2025	4:33:26 PM	36	1287.50	CEUX
GENMAB A/S	16-Apr-2025	4:33:26 PM	36	1287.50	CEUX
GENMAB A/S	16-Apr-2025	4:33:29 PM	5	1287.50	XCSE
GENMAB A/S	16-Apr-2025	4:33:29 PM	36	1287.50	CEUX
GENMAB A/S	16-Apr-2025	4:33:30 PM	17	1287.50	CEUX
GENMAB A/S	16-Apr-2025	4:33:36 PM	14	1287.50	CEUX
GENMAB A/S	16-Apr-2025	4:33:36 PM	43	1287.00	CEUX
GENMAB A/S	16-Apr-2025	4:33:53 PM	81	1288.00	CEUX

206

Exhibit 99.1(a)

APPENDIX Share buy-back programme - Specification for April 14 – April 18, 2025

GENMAB A/S	16-Apr-2025	4:34:07 PM	12	1288.00	CEUX
GENMAB A/S	16-Apr-2025	4:34:22 PM	90	1287.00	XCSE
GENMAB A/S	16-Apr-2025	4:34:22 PM	35	1287.50	XCSE
GENMAB A/S	16-Apr-2025	4:34:22 PM	36	1287.50	CEUX
GENMAB A/S	16-Apr-2025	4:34:22 PM	44	1287.00	CEUX
GENMAB A/S	16-Apr-2025	4:34:23 PM	7	1287.50	XCSE
GENMAB A/S	16-Apr-2025	4:34:29 PM	2	1287.00	CEUX
GENMAB A/S	16-Apr-2025	4:34:32 PM	35	1287.00	XCSE
GENMAB A/S	16-Apr-2025	4:34:32 PM	35	1287.00	XCSE
GENMAB A/S	16-Apr-2025	4:34:32 PM	35	1287.00	XCSE
GENMAB A/S	16-Apr-2025	4:34:55 PM	47	1286.50	TQEX
GENMAB A/S	16-Apr-2025	4:35:35 PM	13	1286.50	TQEX
GENMAB A/S	16-Apr-2025	4:35:35 PM	43	1286.50	AQEU
GENMAB A/S	16-Apr-2025	4:35:48 PM	35	1287.00	XCSE
GENMAB A/S	16-Apr-2025	4:35:48 PM	52	1287.00	XCSE
GENMAB A/S	16-Apr-2025	4:35:48 PM	9	1287.00	XCSE
GENMAB A/S	16-Apr-2025	4:35:48 PM	36	1287.00	CEUX
GENMAB A/S	16-Apr-2025	4:35:49 PM	21	1287.00	CEUX
GENMAB A/S	16-Apr-2025	4:36:15 PM	46	1287.00	XCSE
GENMAB A/S	16-Apr-2025	4:36:15 PM	16	1287.00	XCSE
GENMAB A/S	16-Apr-2025	4:36:15 PM	58	1286.50	TQEX
GENMAB A/S	16-Apr-2025	4:36:15 PM	26	1286.50	AQEU
GENMAB A/S	16-Apr-2025	4:36:16 PM	32	1287.00	XCSE
GENMAB A/S	16-Apr-2025	4:36:16 PM	7	1287.00	XCSE
GENMAB A/S	16-Apr-2025	4:36:16 PM	46	1287.00	XCSE
GENMAB A/S	16-Apr-2025	4:36:16 PM	16	1287.00	XCSE
GENMAB A/S	16-Apr-2025	4:36:16 PM	36	1287.00	CEUX
GENMAB A/S	16-Apr-2025	4:36:18 PM	46	1287.00	XCSE
GENMAB A/S	16-Apr-2025	4:36:18 PM	16	1287.00	XCSE
GENMAB A/S	16-Apr-2025	4:36:18 PM	37	1287.00	XCSE
GENMAB A/S	16-Apr-2025	4:36:22 PM	25	1287.00	XCSE
GENMAB A/S	16-Apr-2025	4:36:22 PM	46	1287.00	XCSE
GENMAB A/S	16-Apr-2025	4:36:22 PM	37	1287.00	XCSE
GENMAB A/S	16-Apr-2025	4:36:23 PM	46	1287.00	XCSE
GENMAB A/S	16-Apr-2025	4:36:23 PM	37	1287.00	XCSE
GENMAB A/S	16-Apr-2025	4:36:23 PM	17	1287.00	XCSE
GENMAB A/S	16-Apr-2025	4:36:23 PM	17	1287.00	XCSE
GENMAB A/S	16-Apr-2025	4:36:23 PM	19	1287.00	XCSE
GENMAB A/S	16-Apr-2025	4:36:23 PM	19	1287.00	XCSE
GENMAB A/S	16-Apr-2025	4:36:23 PM	46	1287.00	XCSE
GENMAB A/S	16-Apr-2025	4:36:23 PM	33	1287.00	XCSE
GENMAB A/S	16-Apr-2025	4:36:23 PM	17	1287.00	XCSE
GENMAB A/S	16-Apr-2025	4:36:23 PM	16	1287.00	XCSE

207

Exhibit 99.1(a)

APPENDIX Share buy-back programme - Specification for April 14 – April 18, 2025

GENMAB A/S	16-Apr-2025	4:36:23 PM	46	1287.00	XCSE
GENMAB A/S	16-Apr-2025	4:36:23 PM	16	1287.00	XCSE
GENMAB A/S	16-Apr-2025	4:36:23 PM	22	1287.00	XCSE
GENMAB A/S	16-Apr-2025	4:36:24 PM	19	1287.00	XCSE
GENMAB A/S	16-Apr-2025	4:36:24 PM	46	1287.00	XCSE
GENMAB A/S	16-Apr-2025	4:36:24 PM	16	1287.00	XCSE
GENMAB A/S	16-Apr-2025	4:36:24 PM	15	1287.00	XCSE
GENMAB A/S	16-Apr-2025	4:36:24 PM	21	1287.00	XCSE
GENMAB A/S	16-Apr-2025	4:36:24 PM	16	1287.00	XCSE
GENMAB A/S	16-Apr-2025	4:36:24 PM	46	1287.00	XCSE
GENMAB A/S	16-Apr-2025	4:36:24 PM	15	1287.00	XCSE
GENMAB A/S	16-Apr-2025	4:36:24 PM	37	1287.00	XCSE
GENMAB A/S	16-Apr-2025	4:36:24 PM	3	1287.00	XCSE
GENMAB A/S	16-Apr-2025	4:36:25 PM	14	1287.00	XCSE
GENMAB A/S	16-Apr-2025	4:36:25 PM	37	1287.00	XCSE
GENMAB A/S	16-Apr-2025	4:36:25 PM	46	1287.00	XCSE
GENMAB A/S	16-Apr-2025	4:36:26 PM	37	1287.00	XCSE
GENMAB A/S	16-Apr-2025	4:36:26 PM	46	1287.00	XCSE
GENMAB A/S	16-Apr-2025	4:36:28 PM	16	1287.00	XCSE
GENMAB A/S	16-Apr-2025	4:36:28 PM	37	1287.00	XCSE
GENMAB A/S	16-Apr-2025	4:36:28 PM	46	1287.00	XCSE
GENMAB A/S	16-Apr-2025	4:36:28 PM	37	1287.00	XCSE
GENMAB A/S	16-Apr-2025	4:36:28 PM	46	1287.00	XCSE
GENMAB A/S	16-Apr-2025	4:36:45 PM	79	1286.00	CEUX
GENMAB A/S	16-Apr-2025	4:36:45 PM	3	1286.00	CEUX
GENMAB A/S	16-Apr-2025	4:36:45 PM	9	1286.00	CEUX
GENMAB A/S	16-Apr-2025	4:36:46 PM	87	1286.00	XCSE
GENMAB A/S	16-Apr-2025	4:36:46 PM	34	1286.00	TQEX
GENMAB A/S	16-Apr-2025	4:36:47 PM	42	1286.50	CEUX
GENMAB A/S	16-Apr-2025	4:36:47 PM	22	1286.50	CEUX
GENMAB A/S	16-Apr-2025	4:36:47 PM	9	1286.50	CEUX
GENMAB A/S	16-Apr-2025	4:36:47 PM	8	1286.50	CEUX
GENMAB A/S	16-Apr-2025	4:36:47 PM	9	1286.50	CEUX
GENMAB A/S	16-Apr-2025	4:37:05 PM	73	1286.00	XCSE
GENMAB A/S	16-Apr-2025	4:37:05 PM	36	1286.50	CEUX
GENMAB A/S	16-Apr-2025	4:37:16 PM	36	1287.50	CEUX
GENMAB A/S	16-Apr-2025	4:37:17 PM	4	1287.50	XCSE
GENMAB A/S	16-Apr-2025	4:37:20 PM	69	1287.50	XCSE
GENMAB A/S	16-Apr-2025	4:37:20 PM	1	1287.50	XCSE
GENMAB A/S	16-Apr-2025	4:37:20 PM	87	1287.50	CEUX
GENMAB A/S	16-Apr-2025	4:37:56 PM	59	1288.50	CEUX
GENMAB A/S	16-Apr-2025	4:37:56 PM	29	1288.50	CEUX
GENMAB A/S	16-Apr-2025	4:37:56 PM	80	1289.00	CEUX

208

Exhibit 99.1(a)

APPENDIX Share buy-back programme - Specification for April 14 – April 18, 2025

GENMAB A/S	16-Apr-2025	4:38:04 PM	36	1289.00	CEUX
GENMAB A/S	16-Apr-2025	4:38:05 PM	36	1289.00	CEUX
GENMAB A/S	16-Apr-2025	4:38:09 PM	91	1289.00	XCSE
GENMAB A/S	16-Apr-2025	4:38:09 PM	15	1289.00	CEUX
GENMAB A/S	16-Apr-2025	4:38:35 PM	3	1288.50	CEUX
GENMAB A/S	16-Apr-2025	4:38:35 PM	37	1288.50	AQEU
GENMAB A/S	16-Apr-2025	4:38:38 PM	9	1288.50	XCSE
GENMAB A/S	16-Apr-2025	4:38:38 PM	24	1288.50	XCSE
GENMAB A/S	16-Apr-2025	4:38:38 PM	26	1288.00	TQEX
GENMAB A/S	16-Apr-2025	4:38:38 PM	36	1288.50	CEUX
GENMAB A/S	16-Apr-2025	4:39:13 PM	36	1288.50	CEUX
GENMAB A/S	16-Apr-2025	4:39:17 PM	35	1288.50	XCSE
GENMAB A/S	16-Apr-2025	4:39:17 PM	6	1288.50	XCSE
GENMAB A/S	16-Apr-2025	4:39:17 PM	23	1288.50	XCSE
GENMAB A/S	16-Apr-2025	4:39:17 PM	14	1288.50	CEUX
GENMAB A/S	16-Apr-2025	4:39:23 PM	16	1288.50	CEUX
GENMAB A/S	16-Apr-2025	4:39:45 PM	58	1287.50	CEUX
GENMAB A/S	16-Apr-2025	4:40:08 PM	7	1289.00	XCSE
GENMAB A/S	16-Apr-2025	4:40:08 PM	6	1288.50	AQEU
GENMAB A/S	16-Apr-2025	4:40:08 PM	6	1288.50	AQEU
GENMAB A/S	16-Apr-2025	4:41:25 PM	24	1289.00	XCSE
GENMAB A/S	16-Apr-2025	4:41:25 PM	66	1289.00	XCSE
GENMAB A/S	16-Apr-2025	4:41:26 PM	36	1290.50	CEUX
GENMAB A/S	16-Apr-2025	4:41:26 PM	36	1290.50	CEUX
GENMAB A/S	16-Apr-2025	4:41:27 PM	36	1290.50	CEUX
GENMAB A/S	16-Apr-2025	4:41:59 PM	48	1290.50	CEUX
GENMAB A/S	16-Apr-2025	4:43:05 PM	92	1290.50	XCSE
GENMAB A/S	16-Apr-2025	4:43:05 PM	34	1290.50	TQEX
GENMAB A/S	16-Apr-2025	4:43:05 PM	28	1290.50	TQEX
GENMAB A/S	16-Apr-2025	4:43:05 PM	86	1290.50	CEUX
GENMAB A/S	16-Apr-2025	4:43:05 PM	51	1290.50	AQEU
GENMAB A/S	16-Apr-2025	4:43:25 PM	20	1290.50	XCSE
GENMAB A/S	16-Apr-2025	4:43:25 PM	17	1290.50	XCSE
GENMAB A/S	16-Apr-2025	4:43:25 PM	46	1290.50	XCSE
GENMAB A/S	16-Apr-2025	4:43:43 PM	16	1290.50	TQEX
GENMAB A/S	16-Apr-2025	4:43:43 PM	4	1290.50	TQEX
GENMAB A/S	16-Apr-2025	4:43:43 PM	4	1290.50	TQEX
GENMAB A/S	16-Apr-2025	4:43:43 PM	2	1290.50	TQEX
GENMAB A/S	16-Apr-2025	4:43:46 PM	18	1290.50	CEUX
GENMAB A/S	16-Apr-2025	4:43:46 PM	25	1290.50	CEUX
GENMAB A/S	16-Apr-2025	4:43:46 PM	12	1290.50	CEUX
GENMAB A/S	16-Apr-2025	4:43:47 PM	7	1290.50	CEUX
GENMAB A/S	16-Apr-2025	4:43:49 PM	36	1290.50	CEUX

209

Exhibit 99.1(a)

APPENDIX Share buy-back programme - Specification for April 14 – April 18, 2025

GENMAB A/S	16-Apr-2025	4:44:09 PM	89	1289.50	CEUX
GENMAB A/S	16-Apr-2025	4:44:49 PM	92	1290.50	XCSE
GENMAB A/S	16-Apr-2025	4:44:49 PM	25	1290.50	TQEX
GENMAB A/S	16-Apr-2025	4:44:49 PM	30	1290.50	CEUX
GENMAB A/S	16-Apr-2025	4:44:49 PM	40	1290.50	CEUX
GENMAB A/S	16-Apr-2025	4:44:49 PM	35	1291.50	CEUX
GENMAB A/S	16-Apr-2025	4:45:07 PM	88	1291.00	CEUX
GENMAB A/S	16-Apr-2025	4:45:19 PM	39	1290.50	XCSE
GENMAB A/S	16-Apr-2025	4:45:19 PM	54	1290.50	XCSE
GENMAB A/S	16-Apr-2025	4:45:19 PM	12	1290.50	TQEX
GENMAB A/S	16-Apr-2025	4:45:19 PM	27	1290.50	TQEX
GENMAB A/S	16-Apr-2025	4:45:19 PM	4	1290.50	TQEX
GENMAB A/S	16-Apr-2025	4:45:19 PM	52	1290.50	AQEU
GENMAB A/S	16-Apr-2025	4:45:19 PM	4	1290.50	AQEU
GENMAB A/S	16-Apr-2025	4:45:45 PM	79	1290.00	CEUX
GENMAB A/S	16-Apr-2025	4:45:45 PM	2	1290.00	CEUX
GENMAB A/S	16-Apr-2025	4:46:05 PM	6	1290.00	CEUX
GENMAB A/S	16-Apr-2025	4:46:09 PM	3	1289.50	TQEX
GENMAB A/S	16-Apr-2025	4:46:09 PM	3	1289.50	TQEX
GENMAB A/S	16-Apr-2025	4:46:09 PM	13	1289.50	TQEX
GENMAB A/S	16-Apr-2025	4:46:09 PM	5	1289.50	TQEX
GENMAB A/S	16-Apr-2025	4:46:09 PM	7	1289.50	TQEX
GENMAB A/S	16-Apr-2025	4:46:09 PM	7	1289.50	TQEX
GENMAB A/S	16-Apr-2025	4:46:09 PM	3	1290.00	CEUX
GENMAB A/S	16-Apr-2025	4:46:09 PM	4	1290.00	CEUX
GENMAB A/S	16-Apr-2025	4:46:09 PM	8	1290.00	CEUX
GENMAB A/S	16-Apr-2025	4:46:09 PM	4	1290.00	CEUX
GENMAB A/S	16-Apr-2025	4:46:09 PM	25	1290.00	CEUX
GENMAB A/S	16-Apr-2025	4:46:12 PM	90	1289.50	XCSE
GENMAB A/S	16-Apr-2025	4:46:12 PM	6	1289.50	TQEX
GENMAB A/S	16-Apr-2025	4:46:12 PM	36	1290.00	CEUX
GENMAB A/S	16-Apr-2025	4:46:12 PM	46	1290.00	AQEU
GENMAB A/S	16-Apr-2025	4:46:35 PM	8	1289.50	TQEX
GENMAB A/S	16-Apr-2025	4:46:37 PM	35	1289.50	AQEU
GENMAB A/S	16-Apr-2025	4:47:05 PM	28	1289.50	CEUX
GENMAB A/S	16-Apr-2025	4:47:05 PM	61	1289.50	CEUX
GENMAB A/S	16-Apr-2025	4:47:11 PM	13	1290.00	XCSE
GENMAB A/S	16-Apr-2025	4:47:11 PM	36	1290.00	CEUX
GENMAB A/S	16-Apr-2025	4:47:13 PM	18	1290.50	XCSE
GENMAB A/S	16-Apr-2025	4:47:13 PM	46	1290.50	XCSE
GENMAB A/S	16-Apr-2025	4:47:13 PM	23	1290.50	XCSE
GENMAB A/S	16-Apr-2025	4:47:13 PM	36	1290.50	CEUX
GENMAB A/S	16-Apr-2025	4:47:13 PM	8	1290.50	CEUX

210

Exhibit 99.1(a)

APPENDIX Share buy-back programme - Specification for April 14 – April 18, 2025

GENMAB A/S	16-Apr-2025	4:47:13 PM	18	1290.50	CEUX
GENMAB A/S	16-Apr-2025	4:47:13 PM	25	1290.50	CEUX
GENMAB A/S	16-Apr-2025	4:47:14 PM	13	1290.50	XCSE
GENMAB A/S	16-Apr-2025	4:47:14 PM	36	1290.50	CEUX
GENMAB A/S	16-Apr-2025	4:47:25 PM	77	1290.00	CEUX
GENMAB A/S	16-Apr-2025	4:47:55 PM	89	1290.00	XCSE
GENMAB A/S	16-Apr-2025	4:47:55 PM	15	1290.50	TQEX
GENMAB A/S	16-Apr-2025	4:47:55 PM	10	1290.00	CEUX
GENMAB A/S	16-Apr-2025	4:48:04 PM	22	1290.00	XCSE
GENMAB A/S	16-Apr-2025	4:48:04 PM	4	1290.00	TQEX
GENMAB A/S	16-Apr-2025	4:48:04 PM	40	1290.00	CEUX
GENMAB A/S	16-Apr-2025	4:48:10 PM	4	1290.00	TQEX
GENMAB A/S	16-Apr-2025	4:48:35 PM	13	1290.00	CEUX
GENMAB A/S	16-Apr-2025	4:48:35 PM	79	1290.00	CEUX
GENMAB A/S	16-Apr-2025	4:48:39 PM	14	1290.50	TQEX
GENMAB A/S	16-Apr-2025	4:48:39 PM	86	1290.00	CEUX
GENMAB A/S	16-Apr-2025	4:48:39 PM	45	1290.50	AQEU
GENMAB A/S	16-Apr-2025	4:48:41 PM	3	1290.50	XCSE
GENMAB A/S	16-Apr-2025	4:48:41 PM	7	1290.50	CEUX
GENMAB A/S	16-Apr-2025	4:48:41 PM	86	1290.50	CEUX
GENMAB A/S	16-Apr-2025	4:48:48 PM	35	1290.50	XCSE
GENMAB A/S	16-Apr-2025	4:48:48 PM	26	1290.50	XCSE
GENMAB A/S	16-Apr-2025	4:48:48 PM	46	1290.50	XCSE
GENMAB A/S	16-Apr-2025	4:48:48 PM	36	1290.50	CEUX
GENMAB A/S	16-Apr-2025	4:48:53 PM	7	1290.50	XCSE
GENMAB A/S	16-Apr-2025	4:48:53 PM	35	1290.50	XCSE
GENMAB A/S	16-Apr-2025	4:48:54 PM	18	1290.50	XCSE
GENMAB A/S	16-Apr-2025	4:48:54 PM	22	1290.50	XCSE
GENMAB A/S	16-Apr-2025	4:48:54 PM	46	1290.50	XCSE
GENMAB A/S	16-Apr-2025	4:48:58 PM	17	1290.50	XCSE
GENMAB A/S	16-Apr-2025	4:48:58 PM	46	1290.50	XCSE
GENMAB A/S	16-Apr-2025	4:49:00 PM	15	1290.00	TQEX
GENMAB A/S	16-Apr-2025	4:49:00 PM	15	1290.00	CEUX
GENMAB A/S	16-Apr-2025	4:49:15 PM	87	1289.50	XCSE
GENMAB A/S	16-Apr-2025	4:49:15 PM	25	1289.50	TQEX
GENMAB A/S	16-Apr-2025	4:49:15 PM	3	1289.50	TQEX
GENMAB A/S	16-Apr-2025	4:49:15 PM	39	1289.50	CEUX
GENMAB A/S	16-Apr-2025	4:49:15 PM	49	1289.50	CEUX
GENMAB A/S	16-Apr-2025	4:49:20 PM	29	1289.50	AQEU
GENMAB A/S	16-Apr-2025	4:49:55 PM	9	1288.50	TQEX
GENMAB A/S	16-Apr-2025	4:49:55 PM	47	1288.50	TQEX
GENMAB A/S	16-Apr-2025	4:49:55 PM	72	1288.50	CEUX
GENMAB A/S	16-Apr-2025	4:49:55 PM	21	1288.50	CEUX

211

Exhibit 99.1(a)

APPENDIX Share buy-back programme - Specification for April 14 – April 18, 2025

GENMAB A/S	16-Apr-2025	4:49:58 PM	18	1288.50	AQEU
GENMAB A/S	16-Apr-2025	4:50:00 PM	46	1288.50	XCSE
GENMAB A/S	16-Apr-2025	4:50:05 PM	43	1288.50	XCSE
GENMAB A/S	16-Apr-2025	4:50:05 PM	2	1288.50	XCSE
GENMAB A/S	16-Apr-2025	4:50:05 PM	12	1288.50	AQEU
GENMAB A/S	16-Apr-2025	4:50:09 PM	17	1288.50	XCSE
GENMAB A/S	16-Apr-2025	4:50:09 PM	46	1288.50	XCSE
GENMAB A/S	16-Apr-2025	4:50:09 PM	36	1288.50	CEUX
GENMAB A/S	16-Apr-2025	4:50:09 PM	12	1288.50	CEUX
GENMAB A/S	16-Apr-2025	4:50:18 PM	46	1288.50	XCSE
GENMAB A/S	16-Apr-2025	4:50:18 PM	20	1288.50	XCSE
GENMAB A/S	16-Apr-2025	4:50:18 PM	37	1288.50	XCSE
GENMAB A/S	16-Apr-2025	4:50:18 PM	29	1288.00	XCSE
GENMAB A/S	16-Apr-2025	4:50:19 PM	59	1288.00	XCSE
GENMAB A/S	16-Apr-2025	4:50:19 PM	32	1288.00	XCSE
GENMAB A/S	16-Apr-2025	4:50:19 PM	46	1288.00	XCSE
GENMAB A/S	16-Apr-2025	4:50:19 PM	19	1288.00	XCSE
GENMAB A/S	16-Apr-2025	4:50:34 PM	3	1288.00	XCSE
GENMAB A/S	16-Apr-2025	4:50:34 PM	46	1288.00	XCSE
GENMAB A/S	16-Apr-2025	4:50:34 PM	15	1288.00	XCSE
GENMAB A/S	16-Apr-2025	4:50:34 PM	23	1288.00	XCSE
GENMAB A/S	16-Apr-2025	4:50:34 PM	15	1288.00	XCSE
GENMAB A/S	16-Apr-2025	4:50:34 PM	15	1288.00	XCSE
GENMAB A/S	16-Apr-2025	4:50:34 PM	51	1288.00	XCSE
GENMAB A/S	16-Apr-2025	4:50:34 PM	46	1288.00	XCSE
GENMAB A/S	16-Apr-2025	4:50:34 PM	19	1288.00	XCSE
GENMAB A/S	16-Apr-2025	4:50:34 PM	30	1287.00	TQEX
GENMAB A/S	16-Apr-2025	4:50:34 PM	44	1287.00	CEUX
GENMAB A/S	16-Apr-2025	4:50:34 PM	36	1287.50	CEUX
GENMAB A/S	16-Apr-2025	4:50:34 PM	14	1288.00	CEUX
GENMAB A/S	16-Apr-2025	4:50:34 PM	12	1288.00	CEUX
GENMAB A/S	16-Apr-2025	4:50:34 PM	6	1288.00	CEUX
GENMAB A/S	16-Apr-2025	4:50:34 PM	19	1288.00	CEUX
GENMAB A/S	16-Apr-2025	4:50:34 PM	14	1288.00	CEUX
GENMAB A/S	16-Apr-2025	4:50:34 PM	6	1288.00	CEUX
GENMAB A/S	16-Apr-2025	4:50:34 PM	6	1288.00	CEUX
GENMAB A/S	16-Apr-2025	4:50:35 PM	25	1288.00	CEUX
GENMAB A/S	16-Apr-2025	4:50:35 PM	8	1288.00	CEUX
GENMAB A/S	16-Apr-2025	4:50:35 PM	36	1288.00	CEUX
GENMAB A/S	16-Apr-2025	4:50:55 PM	46	1288.00	XCSE
GENMAB A/S	16-Apr-2025	4:50:55 PM	23	1288.00	XCSE
GENMAB A/S	16-Apr-2025	4:50:55 PM	7	1288.00	XCSE
GENMAB A/S	16-Apr-2025	4:50:55 PM	46	1288.00	XCSE

212

Exhibit 99.1(a)

APPENDIX Share buy-back programme - Specification for April 14 – April 18, 2025

GENMAB A/S	16-Apr-2025	4:50:55 PM	45	1287.00	CEUX
GENMAB A/S	16-Apr-2025	4:50:56 PM	19	1288.00	XCSE
GENMAB A/S	16-Apr-2025	4:50:56 PM	46	1288.00	XCSE
GENMAB A/S	16-Apr-2025	4:50:56 PM	17	1288.00	XCSE
GENMAB A/S	16-Apr-2025	4:50:56 PM	15	1288.00	XCSE
GENMAB A/S	16-Apr-2025	4:50:56 PM	19	1288.00	XCSE
GENMAB A/S	16-Apr-2025	4:50:56 PM	46	1288.00	XCSE
GENMAB A/S	16-Apr-2025	4:50:56 PM	17	1288.00	XCSE
GENMAB A/S	16-Apr-2025	4:50:56 PM	17	1288.00	XCSE
GENMAB A/S	16-Apr-2025	4:50:56 PM	46	1288.00	XCSE
GENMAB A/S	16-Apr-2025	4:50:56 PM	19	1288.00	XCSE
GENMAB A/S	16-Apr-2025	4:50:56 PM	19	1288.00	XCSE
GENMAB A/S	16-Apr-2025	4:50:56 PM	29	1287.50	TQEX
GENMAB A/S	16-Apr-2025	4:50:56 PM	1	1287.50	TQEX
GENMAB A/S	16-Apr-2025	4:50:57 PM	46	1288.00	XCSE
GENMAB A/S	16-Apr-2025	4:50:58 PM	2	1288.00	XCSE
GENMAB A/S	16-Apr-2025	4:50:58 PM	46	1288.00	XCSE
GENMAB A/S	16-Apr-2025	4:50:58 PM	15	1288.00	XCSE
GENMAB A/S	16-Apr-2025	4:51:00 PM	19	1288.00	XCSE
GENMAB A/S	16-Apr-2025	4:51:00 PM	9	1288.00	CEUX
GENMAB A/S	16-Apr-2025	4:51:02 PM	23	1288.50	AQEU
GENMAB A/S	16-Apr-2025	4:51:14 PM	1	1289.00	XCSE
GENMAB A/S	16-Apr-2025	4:51:14 PM	3	1289.00	XCSE
GENMAB A/S	16-Apr-2025	4:51:14 PM	46	1289.00	XCSE
GENMAB A/S	16-Apr-2025	4:51:14 PM	19	1289.00	XCSE
GENMAB A/S	16-Apr-2025	4:51:14 PM	21	1288.50	TQEX
GENMAB A/S	16-Apr-2025	4:51:14 PM	7	1288.50	TQEX
GENMAB A/S	16-Apr-2025	4:51:35 PM	89	1288.00	XCSE
GENMAB A/S	16-Apr-2025	4:51:35 PM	26	1289.50	XCSE
GENMAB A/S	16-Apr-2025	4:51:35 PM	7	1289.50	XCSE
GENMAB A/S	16-Apr-2025	4:51:35 PM	26	1289.50	XCSE
GENMAB A/S	16-Apr-2025	4:51:35 PM	16	1289.50	XCSE
GENMAB A/S	16-Apr-2025	4:51:35 PM	48	1289.50	XCSE
GENMAB A/S	16-Apr-2025	4:51:35 PM	13	1289.50	XCSE
GENMAB A/S	16-Apr-2025	4:51:35 PM	15	1289.50	XCSE
GENMAB A/S	16-Apr-2025	4:51:35 PM	88	1288.00	CEUX
GENMAB A/S	16-Apr-2025	4:51:35 PM	36	1288.50	AQEU
GENMAB A/S	16-Apr-2025	4:51:49 PM	13	1289.50	CEUX
GENMAB A/S	16-Apr-2025	4:51:49 PM	25	1289.50	CEUX
GENMAB A/S	16-Apr-2025	4:51:54 PM	9	1290.50	CEUX
GENMAB A/S	16-Apr-2025	4:52:04 PM	17	1290.50	CEUX
GENMAB A/S	16-Apr-2025	4:52:04 PM	49	1290.00	CEUX
GENMAB A/S	16-Apr-2025	4:52:06 PM	26	1290.00	TQEX

213

Exhibit 99.1(a)

APPENDIX Share buy-back programme - Specification for April 14 – April 18, 2025

GENMAB A/S	16-Apr-2025	4:52:06 PM	40	1290.00	CEUX
GENMAB A/S	16-Apr-2025	4:52:06 PM	30	1290.00	CEUX
GENMAB A/S	16-Apr-2025	4:52:06 PM	26	1290.00	AQEU
GENMAB A/S	16-Apr-2025	4:52:08 PM	36	1290.00	CEUX
GENMAB A/S	16-Apr-2025	4:52:12 PM	36	1290.00	CEUX
GENMAB A/S	16-Apr-2025	4:52:13 PM	35	1290.00	XCSE
GENMAB A/S	16-Apr-2025	4:52:13 PM	3	1290.00	XCSE
GENMAB A/S	16-Apr-2025	4:52:13 PM	46	1290.00	XCSE
GENMAB A/S	16-Apr-2025	4:52:13 PM	33	1290.00	XCSE
GENMAB A/S	16-Apr-2025	4:52:13 PM	1	1290.00	XCSE
GENMAB A/S	16-Apr-2025	4:52:15 PM	3	1290.00	CEUX
GENMAB A/S	16-Apr-2025	4:52:26 PM	40	1289.50	XCSE
GENMAB A/S	16-Apr-2025	4:52:26 PM	51	1289.50	XCSE
GENMAB A/S	16-Apr-2025	4:52:26 PM	36	1290.00	CEUX
GENMAB A/S	16-Apr-2025	4:52:26 PM	43	1289.50	CEUX
GENMAB A/S	16-Apr-2025	4:52:35 PM	76	1289.00	CEUX
GENMAB A/S	16-Apr-2025	4:52:35 PM	11	1289.00	CEUX
GENMAB A/S	16-Apr-2025	4:52:35 PM	27	1289.00	AQEU
GENMAB A/S	16-Apr-2025	4:52:39 PM	26	1289.00	TQEX
GENMAB A/S	16-Apr-2025	4:53:44 PM	8	1288.50	XCSE
GENMAB A/S	16-Apr-2025	4:53:44 PM	36	1288.50	XCSE
GENMAB A/S	16-Apr-2025	4:53:44 PM	43	1288.50	XCSE
GENMAB A/S	16-Apr-2025	4:53:54 PM	9	1288.50	XCSE
GENMAB A/S	16-Apr-2025	4:53:54 PM	52	1288.00	CEUX
GENMAB A/S	16-Apr-2025	4:53:54 PM	8	1288.50	CEUX
GENMAB A/S	16-Apr-2025	4:53:54 PM	8	1288.50	CEUX
GENMAB A/S	16-Apr-2025	4:53:54 PM	25	1288.50	CEUX
GENMAB A/S	16-Apr-2025	4:53:54 PM	35	1288.00	CEUX
GENMAB A/S	16-Apr-2025	4:53:54 PM	4	1288.00	CEUX
GENMAB A/S	16-Apr-2025	4:53:55 PM	17	1288.50	XCSE
GENMAB A/S	16-Apr-2025	4:53:55 PM	46	1288.50	XCSE
GENMAB A/S	16-Apr-2025	4:53:55 PM	19	1288.50	XCSE
GENMAB A/S	16-Apr-2025	4:53:55 PM	17	1288.50	XCSE
GENMAB A/S	16-Apr-2025	4:53:55 PM	18	1288.50	XCSE
GENMAB A/S	16-Apr-2025	4:53:56 PM	9	1289.00	CEUX
GENMAB A/S	16-Apr-2025	4:54:14 PM	3	1288.50	CEUX
GENMAB A/S	16-Apr-2025	4:54:14 PM	30	1288.50	CEUX
GENMAB A/S	16-Apr-2025	4:54:14 PM	49	1288.50	CEUX
GENMAB A/S	16-Apr-2025	4:54:14 PM	5	1289.00	CEUX
GENMAB A/S	16-Apr-2025	4:54:14 PM	17	1289.00	CEUX
GENMAB A/S	16-Apr-2025	4:54:14 PM	69	1288.50	AQEU
GENMAB A/S	16-Apr-2025	4:54:14 PM	14	1288.50	AQEU
GENMAB A/S	16-Apr-2025	4:54:27 PM	19	1289.50	CEUX

214

Exhibit 99.1(a)

APPENDIX Share buy-back programme - Specification for April 14 – April 18, 2025

GENMAB A/S	16-Apr-2025	4:54:27 PM	12	1289.50	CEUX
GENMAB A/S	16-Apr-2025	4:54:33 PM	59	1291.00	XCSE
GENMAB A/S	16-Apr-2025	4:54:41 PM	12	1291.00	XCSE
GENMAB A/S	16-Apr-2025	4:54:42 PM	14	1292.00	XCSE
GENMAB A/S	16-Apr-2025	4:54:42 PM	13	1292.00	CEUX
GENMAB A/S	16-Apr-2025	4:54:42 PM	69	1291.50	CEUX
GENMAB A/S	16-Apr-2025	4:54:42 PM	24	1291.50	CEUX
GENMAB A/S	16-Apr-2025	4:54:43 PM	46	1292.00	XCSE
GENMAB A/S	16-Apr-2025	4:54:43 PM	2	1292.00	XCSE

215