X0202 SCHEDULE 13G 0001167212 XXXXXXXX LIVE Common Stock, $0.00015 par value 03/31/2026 0001120914 PDF Solutions, Inc. 693282105 2858 De La Cruz Blvd. Santa Clara CA 95050 Rule 13d-1(b) Needham Investment Management L.L.C. b DE 0.00 2022700.00 0.00 2022700.00 2022700.00 N 5.1 IA OO Needham Asset Management, LLC b DE 0.00 2022700.00 0.00 2022700.00 2022700.00 N 5.1 HC OO George A. Needham b X1 0.00 2022700.00 0.00 2022700.00 2022700.00 N 5.1 HC IN PDF Solutions, Inc. 2858 De La Cruz Blvd., Santa Clara, California 95050 Needham Investment Management L.L.C. Needham Asset Management, LLC George A. Needham Needham Investment Management L.L.C. 250 Park Avenue, 10th Floor New York, New York 10117-1099 United States of America Needham Asset Management, LLC c/o Needham Investment Management L.L.C. 250 Park Avenue, 10th Floor New York, New York 10117-1099 United States of America George A. Needham c/o Needham Investment Management L.L.C. 250 Park Avenue, 10th Floor New York, New York 10117-1099 United States of America Needham Investment Management L.L.C. - Delaware Needham Asset Management, LLC - Delaware George A. Needham - United States N IA HC Needham Investment Management L.L.C. - 2,022,700 Needham Asset Management, LLC - 2,022,700 George A. Needham - 2,022,700 Needham Investment Management L.L.C. - 5.1% Needham Asset Management, LLC - 5.1% George A. Needham - 5.1% Needham Investment Management L.L.C. - 0 Needham Asset Management, LLC - 0 George A. Needham - 0 Needham Investment Management L.L.C. - 2,022,700 Needham Asset Management, LLC - 2,022,700 George A. Needham - 2,022,700 Needham Investment Management L.L.C. - 0 Needham Asset Management, LLC - 0 George A. Needham - 0 Needham Investment Management L.L.C. - 2,022,700 Needham Asset Management, LLC - 2,022,700 George A. Needham - 2,022,700 Y N All of the securities reported in this Schedule 13G are directly owned by advisory clients of Needham Investment Management L.L.C. None of those advisory clients may be deemed to beneficially own more than 5% of the Common Stock, $0.00015 par value. N Please see Exhibit B attached hereto. Y Y N By signing below I certify that, to the best of my knowledge and belief, the securities referred to above were acquired and are held in the ordinary course of business and were not acquired and are not held for the purpose of or with the effect of changing or influencing the control of the issuer of the securities and were not acquired and are not held in connection with or as a participant in any transaction having that purpose or effect, other than activities solely in connection with a nomination under ?? 240.14a-11. Exhibit A - Joint Filing Agreement Exhibit B - Control Person Identification Needham Investment Management L.L.C. /s/ James W. Giangrasso 05/15/2026 Needham Asset Management, LLC /s/ James W. Giangrasso 05/15/2026 George A. Needham /s/ George A. Needham 05/15/2026