Venrock Healthcare Capital Partners Reports 4.6% Stake in CytomX Therapeutics

On May 15, 2026, a group of reporting persons led by Venrock Healthcare Capital Partners III, L.P. filed a Schedule 13G/A for CytomX Therapeutics, Inc. (CTMX), reporting a 4.6% ownership stake consisting of 9,982,124 shares of common stock. This filing represents an increase from a previously reported 0% position. The aggregate ownership is distributed across several entities: VHCP III holds 2,107,644 shares, VHCP Co-Investment III holds 210,912 shares, and VHCP EG holds 7,663,568 shares. VHCP Management III and VHCP Management EG serve as the general partners or managers for these entities, with Nimish Shah and Bong Koh acting as the voting members. The ownership percentage calculation accounts for a total of 216,177,309 shares outstanding, following a significant public offering that closed on March 19, 2026. The reporting persons have certified that the shares were acquired in the ordinary course of business and not for the purpose of influencing or changing the control of the issuer.