X0306 4 2019-07-01 0 0001764925 Slack Technologies, Inc. WORK 0001715450 Palihapitiya Chamath C/O SOCIAL CAPITAL 120 HAWTHORNE AVENUE PALO ALTO CA 94301 1 0 1 0 Class A Common Stock 2019-07-01 4 J 0 223 0.00 A 223 I See Footnotes Class A Common Stock 575316 I See Footnotes Class A Common Stock 9956715 I See Footnotes Class A Common Stock 1164243 I See Footnotes The shares were obtained pursuant to a distribution from another shareholder of the Issuer at no consideration. The shares are held by The Hello Warrior Family Trust (the "Trust"). The Reporting Person is a trustee of the Trust and may be deemed to share voting and dispositive power with regard to the reported shares held by the Trust. The shares are held by The Social+Capital Partnership III, L.P. (the "SC III") for itself and as nominee for The Social+Capital Partnership Principals Fund III, L.P. (the "Principals III"). The Social+Capital Partnership GP III, Ltd. (the "GP III Ltd.") is the general partner of The Social+Capital Partnership GP III, L.P. (the "GP III LP"), which is the general partner of SC III. The sole member of GP III Ltd. is Social Capital Holdings Inc. ("SC Holdings"). GP III Ltd. has sole voting and dispositive power with regard to the shares held by SC III. The shares are held by The Social+Capital Partnership II, L.P., (the "SC II") for itself and as nominee for certain other individuals and entities. The Social+Capital Partnership GP II, Ltd.(the "GP II Ltd.") is the general partner of The Social+Capital Partnership GP II, L.P. (the "GP II LP"), which is the general partner of SC II. The sole member of GP II Ltd. is SC Holdings. GP II Ltd. has sole voting and dispositive power with regard to the shares held by SC II. The shares are held by The Social+Capital Partnership Opportunities Fund, L.P., (the "SCP Opportunities Fund"). The Social+Capital Partnership Opportunities Fund GP, Ltd. (the "Opportunities GP Ltd.") is the general partner of The Social+Capital Partnership Opportunities Fund GP, L.P. (the "Opportunities GP LP"), which is the general partner of SCP Opportunities Fund. The sole member of Opportunities GP Ltd. is SC Holdings. Opportunities GP Ltd. has sole voting and dispositive power with regard to the shares held by SCP Opportunities Fund. Chamath Palihapitiya is the Chief Executive Officer of SC Holdings and holds voting and dispositive power over shares controlled by GP II Ltd., GP III Ltd., and Opportunities GP Ltd. /s/Chamath Palihapitiya 2019-07-03