X0508 4 2023-10-09 0001042074 CymaBay Therapeutics, Inc. CBAY 0001588861 Shah Sujal C/O CYMABAY THERAPEUTICS, INC. 7575 GATEWAY BLVD., SUITE 110 NEWARK CA 94560 1 1 0 0 Chief Executive Officer 1 Common Stock 2023-10-09 4 M 0 64861 5.00 A 236162 D Common Stock 2023-10-09 4 S 0 64861 14.2040 D 171301 D Employee Stock Option (right to buy) 5.00 2023-10-09 4 M 0 31034 0 D 2023-12-22 Common Stock 31034 62072 D Stock Appreciation Right 5.00 2023-10-09 4 M 0 12972 0 D 2023-12-22 Common Stock 12972 25945 D Employee Stock Option (right to buy) 5.00 2023-10-09 4 M 0 20855 0 D 2024-01-05 Common Stock 20855 41711 D The sales reported in this Form 4 were effected pursuant to a Rule 10b5-1 trading plan entered into on June 28, 2023. The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $14.07 to $14.35, inclusive. The reporting person undertakes to provide to CymaBay Therapeutics, Inc., any security holder of CymaBay Therapeutics, Inc., or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the range set forth in this footnote. The option vested over a four-year period, with one-third of the shares subject to the option vesting on the grant date of December 23, 2013, and the remaining 2/3 of the shares subject to the option vesting ratably on a monthly basis over the 48 months thereafter. The award was granted under the CymaBay 2013 Equity Incentive Plan and can be settled in cash or shares of CymaBay common stock, at the sole discretion of CymaBay. The award vested in full on the two-year anniversary of the grant date. The option vested over a four-year period, with one-third of the shares subject to the Option vesting on the grant date of January 6, 2014, and the remaining 2/3 of the shares subject to the Option vesting ratably on a monthly basis over the 48 months. /s/ Paul Quinlan, as attorney-in-fact for Sujal Shah 2023-10-09