CytomX Therapeutics CTMX Institutional Ownership

Updated Oct 11, 2026

CytomX Therapeutics, Inc. (NASDAQ:CTMX) had 179 institutional holders reporting a position on Form 13F for the quarter ended June 30, 2026.

• Together they owned 97.29% of the outstanding stock in Q2 2026, up from 88.73% a quarter earlier.
• Total shares held in CTMX rose 10.26% from Q1 2026; the number of holders rose 120.99% from Q2 2025.
• Of the 179 holders, 118 added to their positions, 33 reduced their stakes and 28 left their positions unchanged in Q2 2026.
• Altogether, institutional holders owned 213Mn CTMX shares at the end of Q2 2026, up 19.83Mn from the prior quarter and up 80.12Mn from a year earlier.
• FMR LLC was the top holder of CytomX Therapeutics as of June 30, 2026, with 32.71Mn shares, or 14.94% of shares outstanding.
• Among holders that already owned CytomX Therapeutics, the biggest buyers in Q2 2026 were BlackRock, Inc. (+12.33Mn shares), Kynam Capital Management, LP (+6.69Mn shares), State Street Corp (+6.08Mn shares), Bank of America Corp (+4.88Mn shares) and Geode Capital Management, LLC (+2.61Mn shares).
• The biggest cuts to CTMX positions during Q2 2026 came from Venrock Adviser, LLC (-5Mn shares), Citadel Advisors LLC (-2.3Mn shares), Millennium Management LLC (-1.97Mn shares), Susquehanna International Group, LLP (-1.78Mn shares) and Marshall Wace, LLP (-1.11Mn shares).
• Per Business Quant, the top 10 investors in CTMX for the quarter ended June 30, 2026 were FMR LLC (32.71Mn shares), Kynam Capital Management, LP (21.7Mn shares), BlackRock, Inc. (17.56Mn shares), Bank of America Corp (15.08Mn shares), State Street Corp (11.75Mn shares), Perceptive Advisors LLC (10.44Mn shares), Vanguard Capital Management LLC (8.53Mn shares), Point72 Asset Management, L.P. (7.81Mn shares), Wellington Management Group LLP (5.17Mn shares) and Venrock Adviser, LLC (4.98Mn shares).