X0609 4 2026-07-01 0001120914 PDF SOLUTIONS INC PDFS 0001892306 Strojwas Andrzej false 2858 DE LA CRUZ BLVD. SANTA CLARA CA 95050 1 Chief Technology Officer 0 Common Stock 2026-07-01 4 F 0 1356 66.88 D 88843 D Common Stock 2026-07-01 4 A 0 5360 A 94203 D This represents a disposition of shares to the Company to satisfy tax withholding obligations with respect to the vesting of Restricted Stock Units. This is not a sale of shares in the market. Includes 995 shares of common stock that were purchased on January 31, 2026 under the PDF Employee Stock Purchase Plan. These shares represent an award of restricted stock units (Total RSU). 12.5% of the Total RSUs shall vest on the date that is six (6) months after the Vesting Start Date and 12.5% of the Total RSUs shall vest on each date that is six (6) months thereafter until fully vested, subject to the Recipient's continued service through each applicable vesting date. /s/ Adnan Raza, Attorney-In-Fact for Andrzej Strojwas 2026-07-02