CytomX Therapeutics, Inc. (CTMX) shareholders
CTMXNasdaqPharmaceutical PreparationsFiscal year ends December 31
$2.04+0.00 (0.00%)
Close on Nov 13, 2026Market cap $444.52MP/E –Yield –
Ownership
Institutional holdings as of Jun 30, 2026, from 13F filings
Held by institutions
97.9%
213M of 218M shares
Institutional holders
179
47 new, 45 sold out
Net institutional buying
20M
In Q2 2026
Insider trades, 12 months
0 buys · 5 sales
Net sold $1.23M
Shares held by institutions
Holders of more than 5%
Latest Schedule 13D (active) or 13G (passive) filed by each holder
| Holder | Shares | % of class | Filing | As of |
|---|---|---|---|---|
| Abigail P. Johnson Joint filing with FMR LLC (14.60%) | 24,688,109 | 14.60% | 13G (passive) amendment | Dec 31, 2025 |
| BlackRock, Inc. | 16,551,452 | 7.60% | 13G (passive) | Jun 30, 2026 |
| Venrock Healthcare Capital Partners EG, L.P. Joint filing with Venrock Healthcare Capital Partners III, L.P. (9.40%), VHCP Co-Investment Holdings III, LLC (9.40%) and 4 more | 15,561,500 | 9.40% | 13G (passive) amendment | Sep 30, 2025 |
| FMR LLC Joint filing with Abigail P. Johnson (9.30%) | 15,396,200 | 9.30% | 13G (passive) amendment | Sep 30, 2025 |
| Juliet Tammenoms Bakker Joint filing with Patrick G. Enright (7.00%), Longitude Capital Partners V, LLC (5.70%) and 1 more | 15,288,461 | 7.00% | 13G (passive) amendment | Mar 31, 2026 |
| VHCP Management EG, LLC Joint filing with Venrock Healthcare Capital Partners III, L.P. (8.20%), VHCP Co-Investment Holdings III, LLC (8.20%) and 4 more | 12,992,500 | 8.20% | 13G (passive) | May 13, 2025 |
| Bank Of America Corp /De/ | 11,867,012 | 5.40% | 13G (passive) amendment | Sep 30, 2026 |
| Kevin Tang Joint filing with Tang Capital Management, LLC (7.00%) | 11,065,662 | 7.00% | 13G (passive) amendment | Jun 30, 2025 |
| Perceptive Life Sciences Master Fund, Ltd. Joint filing with Perceptive Advisors LLC (5.90%), Joseph Edelman (5.90%) | 9,680,185 | 5.90% | 13G (passive) | Aug 14, 2025 |
| Yue Tang Joint filing with Kynam Capital Management, LP (5.29%), Kynam Capital Management GP, LLC (5.29%) | 8,966,077 | 5.29% | 13G (passive) | Dec 31, 2025 |
| Tang Capital Management, LLC Joint filing with Tang Capital Partners, LP (9.80%), Kevin Tang (9.80%) | 6,550,000 | 9.80% | 13G (passive) amendment | Dec 31, 2023 |
| Kynam Capital Management GP, LLC Joint filing with Kynam Capital Management, LP (9.96%), Yue Tang (9.96%) | 0 | 9.96% | 13G (passive) amendment | Jun 30, 2026 |
Top institutional holders
13F holdings as of Jun 30, 2026
| Holder | Shares | % of CTMX | Value | Change | % of portfolio |
|---|---|---|---|---|---|
| FMR LLC | 32,714,937 | 15.01% | $122.68M | +759,300 | 0.01% |
| Kynam Capital Management, LP | 21,703,093 | 9.96% | $81.39M | +6,690,000 | 4.50% |
| BlackRock, Inc. | 17,559,822 | 8.06% | $65.85M | +12,331,542 | 0.00% |
| Bank Of America Corp /De/ | 15,082,617 | 6.92% | $56.56M | +4,879,832 | 0.00% |
| State Street Corp | 11,747,236 | 5.39% | $44.05M | +6,083,828 | 0.00% |
| Perceptive Advisors LLC | 10,439,185 | 4.79% | $39.15M | +340,361 | 0.59% |
| Vanguard Capital Management LLC | 8,525,457 | 3.91% | $31.97M | −207,661 | 0.00% |
| Point72 Asset Management, L.P. | 7,811,033 | 3.58% | $29.29M | −64,357 | 0.03% |
| Wellington Management Group Llp | 5,168,961 | 2.37% | $19.38M | +1,585,976 | 0.00% |
| VR Adviser, LLC | 4,982,124 | 2.29% | $18.68M | −5,000,000 | 0.57% |
| Baker Bros. Advisors LP | 4,975,826 | 2.28% | $18.66M | – | 0.09% |
| Geode Capital Management, LLC | 4,678,716 | 2.15% | $17.55M | +2,612,104 | 0.00% |
| Elmind Capital, LP | 4,550,000 | 2.09% | $17.06M | – | 4.29% |
| Nextech Invest, Ltd. | 4,449,932 | 2.04% | $16.69M | – | 0.79% |
| Two Sigma Investments, LP | 4,132,643 | 1.90% | $15.50M | +1,422,487 | 0.01% |
| Eversept Partners, LP | 3,558,497 | 1.63% | $13.34M | +369,983 | 0.69% |
| UBS Group AG | 3,468,359 | 1.59% | $13.01M | +348,204 | 0.00% |
| Siren, L.L.C. | 3,457,711 | 1.59% | $12.97M | – | 0.26% |
| ADAR1 Capital Management, LLC | 3,365,118 | 1.54% | $12.62M | −45,072 | 0.58% |
| Citadel Advisors LLC | 3,110,509 | 1.43% | $11.66M | −2,295,684 | 0.00% |
Institutional buying and selling by quarter
Positions opened, added to, reduced and closed by 13F filers
| Quarter | Holders | Shares held | % of shares | New / added | Reduced / closed | Shares bought | Shares sold |
|---|---|---|---|---|---|---|---|
| Q2 2026 | 179 | 213M | 97.9% | 47 / 72 | 33 / 45 | 49M | 29M |
| Q1 2026 | 179 | 193M | 88.7% | 77 / 59 | 28 / 19 | 94M | 37M |
| Q4 2025 | 122 | 144M | 66.1% | 39 / 38 | 26 / 20 | 38M | 32M |
| Q3 2025 | 103 | 137M | 63.1% | 32 / 29 | 25 / 12 | 31M | 27M |
| Q2 2025 | 83 | 134M | 61.3% | 29 / 27 | 17 / 12 | 104M | 15M |
| Q1 2025 | 66 | 45M | 20.8% | 7 / 20 | 26 / 11 | 5M | 6M |
| Q4 2024 | 70 | 47M | 21.4% | 12 / 24 | 21 / 10 | 7M | 12M |
| Q3 2024 | 69 | 51M | 23.5% | 10 / 18 | 23 / 13 | 8M | 6M |
| Q2 2024 | 74 | 51M | 23.3% | 13 / 29 | 24 / 27 | 18M | 13M |
| Q1 2024 | 88 | 46M | 21.2% | 28 / 19 | 24 / 8 | 16M | 2M |
| Q4 2023 | 68 | 33M | 15.0% | 9 / 16 | 20 / 3 | 1M | 1M |
| Q3 2023 | 62 | 32M | 14.9% | 3 / 11 | 25 / 8 | 1M | 2M |
Top mutual fund and ETF holders
Latest monthly portfolio reports (Form N-PORT)
128 funds held CTMX in Q2 2026, 44% of their shares through ETFs. Each fund counts once per quarter, from its quarter-end report.
| Fund | Shares | % of CTMX | Value | % of fund | As of |
|---|---|---|---|---|---|
| State Street(R) SPDR(R) S&P(R) Biotech ETF | 7,964,209 | 3.65% | $29.87M | 0.28% | Jun 30, 2026 |
| Vanguard Total Stock Market Index Fund | 6,230,387 | 2.86% | $23.36M | 0.00% | Jun 30, 2026 |
| Select Health Care Portfolio | 5,000,000 | 2.29% | $18.00M | 0.31% | May 31, 2026 |
| iShares Russell 2000 ETF | 4,607,592 | 2.11% | $17.28M | 0.02% | Jun 30, 2026 |
| Fidelity Small Cap Growth Fund | 3,970,290 | 1.82% | $12.31M | 0.14% | Jul 31, 2026 |
| Select Biotechnology Portfolio | 2,774,340 | 1.27% | $9.99M | 0.19% | May 31, 2026 |
| Strategic Advisers Fidelity U.S. Total Stock Fund | 2,652,100 | 1.22% | $9.55M | 0.00% | May 31, 2026 |
| Fidelity Advisor Health Care Fund | 2,500,000 | 1.15% | $7.75M | 0.25% | Jul 31, 2026 |
| Fidelity Advisor Biotechnology Fund | 2,490,551 | 1.14% | $7.72M | 0.35% | Jul 31, 2026 |
| Fidelity Stock Selector Small Cap Fund | 2,450,510 | 1.12% | $7.60M | 0.10% | Jul 31, 2026 |
| Vanguard Extended Market Index Fund | 2,096,625 | 0.96% | $7.86M | 0.01% | Jun 30, 2026 |
| Fidelity Small Cap Growth K6 Fund | 1,988,030 | 0.91% | $6.16M | 0.13% | Jul 31, 2026 |
| Fidelity Small Cap Index Fund | 1,947,498 | 0.89% | $6.04M | 0.02% | Jul 31, 2026 |
| Fidelity Series Small Cap Opportunities Fund | 1,736,495 | 0.80% | $5.38M | 0.11% | Jul 31, 2026 |
| Fidelity U.S. Equity Central Fund | 1,420,000 | 0.65% | $5.33M | 0.02% | Jun 30, 2026 |
Officers, directors and major owners
People who filed Forms 3, 4 or 5 in the last two years
| Name | Role | Shares owned | % of shares | Latest filing |
|---|---|---|---|---|
| Sean A. McCarthy | CEO, Director | 2,263,891 | 1.04% | Oct 16, 2026 |
| Alejandra Carvajal | Chief Legal Officer | 100,000 | 0.05% | Aug 5, 2026 |
| Christopher Ogden | Chief Financial Officer | 295,324 | 0.14% | Jun 17, 2026 |
| Marcia Belvin | SVP, Chief Scientific Officer | 300,760 | 0.14% | Mar 19, 2026 |
| Yu-Waye Chu | Chief Medical Officer | 189,446 | 0.09% | Mar 19, 2026 |
| Rachael Lester | Chief Business Officer | 20,000 | 0.01% | Feb 4, 2026 |
| Lloyd A. Rowland | General Counsel | 120,594 | 0.06% | Mar 20, 2025 |
| Charles S. Fuchs | Director | – | – | Jul 30, 2026 |
| Halley E. Gilbert | Director | – | – | Jun 22, 2026 |
| Matthew P. Young | Director | – | – | Jun 22, 2026 |
| Alan Ashworth | Director | – | – | Jun 22, 2026 |
| James R. Meyers | Director | – | – | Jun 22, 2026 |
| Elaine V. Jones | Director | 5,142 | 0.00% | Jun 22, 2026 |
| Zhen Su | Director | – | – | Jun 22, 2026 |
| Mani Mohindru | Director | – | – | Jun 22, 2026 |
Insider trades
Common stock transactions reported on Form 4, newest first
| Insider | Date | Transaction | Shares | Price | Value | Shares after |
|---|---|---|---|---|---|---|
| Alejandra Carvajal Chief Legal Officer | Aug 3, 2026 | Award | +100,000 | – | – | 100,000 |
| Christopher Ogden Chief Financial Officer | Jun 15, 2026 | Sale | −1,624 | $3.05 | $4.95K | 295,324 |
| Christopher Ogden Chief Financial Officer | Mar 17, 2026 | Sale | −19,323 | $6.42 | $124.05K | 296,948 |
| Sean A. McCarthy CEO, Director | Mar 17, 2026 | Sale(10b5-1 plan) | −118,969 | $6.42 | $763.78K | 1,078,922 |
| Marcia Belvin SVP, Chief Scientific Officer | Mar 17, 2026 | Sale | −31,492 | $6.42 | $202.18K | 300,760 |
| Yu-Waye Chu Chief Medical Officer | Mar 17, 2026 | Sale | −21,279 | $6.42 | $136.61K | 189,446 |
| Sean A. McCarthy CEO, Director | Feb 2, 2026 | Award | +210,000 | – | – | 1,197,891 |
| Yu-Waye Chu Chief Medical Officer | Feb 2, 2026 | Award | +75,000 | – | – | 210,725 |
| Marcia Belvin SVP, Chief Scientific Officer | Feb 2, 2026 | Award | +60,000 | – | – | 332,252 |
| Christopher Ogden Chief Financial Officer | Feb 2, 2026 | Award | +90,000 | – | – | 316,271 |
| Rachael Lester Chief Business Officer | Feb 2, 2026 | Award | +20,000 | – | – | 20,000 |
| Sean A. McCarthy CEO, Director | Nov 6, 2025 | Sale(10b5-1 plan) | −101,793 | $4.54 | $461.91K | 1,089,684 |
| Sean A. McCarthy CEO, Director | Nov 6, 2025 | Option exercise | +101,793 | $1.59 | $161.85K | 1,191,477 |
| Sean A. McCarthy CEO, Director | Nov 6, 2025 | Sale(10b5-1 plan) | −101,793 | $4.54 | $462.14K | 987,891 |
| Marcia Belvin SVP, Chief Scientific Officer | Jun 16, 2025 | Sale | −13,884 | $2.69 | $37.35K | 272,252 |
| Christopher Ogden Chief Financial Officer | Jun 16, 2025 | Sale | −10,614 | $2.69 | $28.55K | 226,271 |
| Sean A. McCarthy CEO, Director | Jun 16, 2025 | Sale | −55,511 | $2.69 | $149.32K | 1,089,684 |
| Marcia Belvin SVP, Chief Scientific Officer | Jun 13, 2025 | Option exercise | +37,500 | – | – | 286,136 |
| Christopher Ogden Chief Financial Officer | Jun 13, 2025 | Sale | −1,641 | $2.95 | $4.84K | 199,385 |
| Christopher Ogden Chief Financial Officer | Jun 13, 2025 | Option exercise | +37,500 | – | – | 236,885 |
| Sean A. McCarthy CEO, Director | Jun 13, 2025 | Option exercise | +150,000 | – | – | 1,145,195 |
| Christopher Ogden Chief Financial Officer | Mar 18, 2025 | Sale | −8,551 | $0.60 | $5.13K | 201,026 |
| Marcia Belvin SVP, Chief Scientific Officer | Mar 18, 2025 | Sale | −19,512 | $0.60 | $11.71K | 248,636 |
| Sean A. McCarthy CEO, Director | Mar 18, 2025 | Sale | −37,656 | $0.60 | $22.59K | 995,195 |
| Yu-Waye Chu Chief Medical Officer | Mar 18, 2025 | Sale | −4,025 | $0.60 | $2.42K | 135,725 |
| Lloyd A. Rowland General Counsel | Mar 18, 2025 | Sale | −10,203 | $0.60 | $6.12K | 120,594 |
| Marcia Belvin SVP, Chief Scientific Officer | Feb 4, 2025 | Award | +35,000 | – | – | 210,648 |
| Marcia Belvin SVP, Chief Scientific Officer | Feb 4, 2025 | Award | +57,500 | – | – | 268,148 |
| Yu-Waye Chu Chief Medical Officer | Feb 4, 2025 | Award | +56,000 | – | – | 82,250 |
| Yu-Waye Chu Chief Medical Officer | Feb 4, 2025 | Award | +57,500 | – | – | 139,750 |
| Sean A. McCarthy CEO, Director | Feb 4, 2025 | Award | +180,000 | – | – | 837,851 |
| Sean A. McCarthy CEO, Director | Feb 4, 2025 | Award | +195,000 | – | – | 1,032,851 |
| Christopher Ogden Chief Financial Officer | Feb 4, 2025 | Award | +57,500 | – | – | 209,577 |
| Christopher Ogden Chief Financial Officer | Feb 4, 2025 | Award | +44,000 | – | – | 152,077 |
| Marcia Belvin SVP, Chief Scientific Officer | Feb 4, 2025 | Award | +57,500 | – | – | 263,148 |
| Marcia Belvin SVP, Chief Scientific Officer | Feb 4, 2025 | Award | +30,000 | – | – | 205,648 |
| Christopher Ogden Chief Financial Officer | Aug 20, 2024 | Sale | −1,984 | $1.23 | $2.44K | 108,077 |
| Christopher Ogden Chief Financial Officer | Aug 20, 2024 | Option exercise | +6,875 | – | – | 110,061 |
| Jeffrey B. Landau Chief Business Officer | Aug 20, 2024 | Sale | −4,181 | $1.23 | $5.14K | 119,056 |
| Jeffrey B. Landau Chief Business Officer | Aug 20, 2024 | Option exercise | +11,250 | – | – | 123,237 |
| Marcia Belvin SVP, Chief Scientific Officer | Aug 20, 2024 | Sale | −4,181 | $1.23 | $5.14K | 175,648 |
| Marcia Belvin SVP, Chief Scientific Officer | Aug 20, 2024 | Option exercise | +11,250 | – | – | 179,829 |
| Sean A. McCarthy CEO, Director | Aug 20, 2024 | Option exercise | +37,500 | – | – | 671,749 |
| Sean A. McCarthy CEO, Director | Aug 20, 2024 | Sale | −13,898 | $1.23 | $17.09K | 657,851 |
| Lloyd A. Rowland General Counsel | Aug 20, 2024 | Sale | −4,181 | $1.23 | $5.14K | 130,797 |
| Lloyd A. Rowland General Counsel | Aug 20, 2024 | Option exercise | +11,250 | – | – | 134,978 |
| Christopher Ogden Chief Financial Officer | Jun 12, 2024 | Award | +17,500 | – | – | 103,186 |
| Sean A. McCarthy CEO, Director | Mar 26, 2024 | Option exercise | +109,768 | $1.57 | $172.34K | 634,249 |
| Christopher Ogden SVP, Finance and Accounting | Mar 19, 2024 | Sale | −2,971 | $2.09 | $6.21K | 85,686 |
| Lloyd A. Rowland General Counsel | Mar 19, 2024 | Sale | −5,268 | $2.09 | $11.01K | 117,728 |
| Sean A. McCarthy CEO, Director | Mar 19, 2024 | Sale | −20,223 | $2.09 | $42.27K | 524,481 |
| Marcia Belvin SVP, Chief Scientific Officer | Mar 19, 2024 | Sale | −12,795 | $2.09 | $26.74K | 168,579 |
| Jeffrey B. Landau Chief Business Officer | Mar 19, 2024 | Sale | −6,562 | $2.09 | $13.71K | 110,060 |
| Sean A. McCarthy CEO, Director | Jan 18, 2024 | Award | +90,000 | – | – | 544,704 |
| Yu-Waye Chu Chief Medical Officer | Jan 18, 2024 | Award | +26,250 | – | – | 26,250 |
| Marcia Belvin SVP, Chief Scientific Officer | Jan 18, 2024 | Award | +26,250 | – | – | 181,374 |
| Jeffrey B. Landau Chief Business Officer | Jan 18, 2024 | Award | +30,000 | – | – | 116,622 |
| Christopher Ogden SVP, Finance and Accounting | Jan 18, 2024 | Award | +40,000 | – | – | 88,657 |
| Lloyd A. Rowland General Counsel | Jan 18, 2024 | Award | +25,000 | – | – | 122,996 |
| Christopher Ogden SVP, Finance and Accounting | Dec 20, 2023 | Sale | −1,990 | $1.38 | $2.75K | 48,657 |
Awards, option exercises, tax withholding and gifts are shown alongside open-market buys and sales. Each name links to the filing on SEC EDGAR.
Short interest
Shares sold short and not yet bought back, as of Oct 30, 2026 (FINRA, reported twice a month)
Short % of float
21.08%
45M shares short
Days to cover
12.0
At 4M shares a day
Change since last report
+5.7%
From 43M shares
Short volume, 20 days
48.2%
Of volume reported to FINRA
Shares sold short, last 12 months
Short sale volume counts trades marked short on any given day, including market-maker hedging, so it runs far higher than the share of CytomX Therapeutics's stock actually held short. Settlement fails (shares not delivered on time) peaked at 135,965 shares on Sep 10, 2026 over the last 90 days.
Planned insider sales
Notices of proposed sale filed on Form 144 before shares are sold
| Seller | Filed | Shares | Market value | Planned sale | Acquired through |
|---|---|---|---|---|---|
| Sean A. McCarthy CEO | Nov 6, 2025 | 101,793 | $461.91K | Nov 6, 2025 | Stock Option |
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