CytomX Therapeutics, Inc.
CytomX Therapeutics, Inc. (CTMX) Stock Ownership
Institutional vs insider vs public ownership from 13F and float data — top holders, activity, and insider trades below.
SEC 13F · FMP · CTMX · as of Mar 31, 2025
Ownership Breakdown
67
Institutional Holders
▼ 4 vs Q4
$28.81M
Total Inst. Value
▼ $19.30M vs Q4
160.82M
Shares Outstanding
freeFloat 87.00%
45.27M
13F Shares Held
▼ 1.44M vs Q4
Institutional ownership = 13F shares ÷ total outstanding. Insider % = 100 − free float. Public % = free float − institution %. Data: FMP /symbol-positions-summary + /shares-float + SEC EDGAR.
Top Institutional Holders
CTMX largest shareholders · institutional ownership
Q1 2025 · SEC 13F
Showing top 10 holders
| Holder | Shares | % Owned | Weight | Value | Reported | Change |
|---|---|---|---|---|---|---|
TANG CAPITAL MANAGEMENT LLC pharmaceutical preparations | 6.72M | 7.71% | 7.71% | $4.27B | May 15, 2025 | ▼ 593.9K |
BVF INC/IL pharmaceutical preparations | 5.23M | 6.00% | 6.00% | $3.32B | May 15, 2025 | — held |
VANGUARD GROUP INC pharmaceutical preparations | 5.12M | 5.87% | 5.87% | $3.25B | May 9, 2025 | ▼ 44.9K |
PROSIGHT MANAGEMENT, LP pharmaceutical preparations | 3.93M | 4.51% | 4.51% | $2.50B | May 15, 2025 | ▲ 25.0K |
ACADIAN ASSET MANAGEMENT LLC pharmaceutical preparations | 3.23M | 3.71% | 3.71% | $2.05B | May 21, 2025 | ▲ 97.0K |
MILLENNIUM MANAGEMENT LLC pharmaceutical preparations | 2.83M | 3.24% | 3.24% | $1.80B | May 15, 2025 | ▼ 394.7K |
POINT72 ASSET MANAGEMENT, L.P. pharmaceutical preparations | 2.65M | 3.04% | 3.04% | $1.68B | Jul 21, 2025 | — held |
WOODLINE PARTNERS LP pharmaceutical preparations | 1.66M | 1.90% | 1.90% | $1.05B | May 15, 2025 | ▲ 1.66M |
LAURION CAPITAL MANAGEMENT LP pharmaceutical preparations | 1.29M | 1.48% | 1.48% | $822.53M | May 15, 2025 | ▲ 45.3K |
BLACKROCK, INC. pharmaceutical preparations | 1.17M | 1.34% | 1.34% | $741.59M | May 2, 2025 | ▼ 73.4K |
Data from SEC Form 13F filings. Ownership bar normalised to largest holder. Change flags: isNew / isSoldOut / changeInSharesNumber (FMP extract-analytics/holder).
Institutional Activity
Q1 2025 vs prior quarter
Q1 2025
20
Increased
+3.74M shares4
New Positions
first time holders17
Decreased
−4.56M shares0
Sold Out
fully exitedNet shares change (top 50)
825.0K
+3.74M / −4.56M
Net new holders
+7
4 new / 0 exited
Based on top 50 institutional holders by position size. Fields: isNew, isSoldOut, changeInSharesNumber (FMP extract-analytics/holder, limit=50).
Insider Buying vs Selling
CTMX insider trading · insider activity
Source: SEC Form 4
Insiders have been primarily selling shares recently. Selling may be driven by pre-scheduled Rule 10b5-1 plans rather than negative sentiment.
11
Buy transactions
4
Sell transactions
2.75
Buy/Sell ratio
$0M
Total disposed
Recent Insider Transactions
Showing 10 most recent · Common Stock only
| Name · Role | Date | Type | Shares | Price | Value | After Trans. | Filing |
|---|---|---|---|---|---|---|---|
Chu Yu-Waye Chief Medical Officer | Mar 17, 2026 | Sale | 21,279 | $6.42 | $136.7K | 189.4K | Form 4 ↗ |
McCarthy Sean A. CEO | Mar 17, 2026 | Sale | 118,969 | $6.42 | $764.1K | 1.08M | Form 4 ↗ |
BELVIN MARCIA SVP, Chief Scientific Officer | Mar 17, 2026 | Sale | 31,492 | $6.42 | $202.3K | 300.8K | Form 4 ↗ |
Ogden Christopher Chief Financial Officer | Mar 17, 2026 | Sale | 19,323 | $6.42 | $124.1K | 296.9K | Form 4 ↗ |
Lester Rachael Chief Business Officer | Feb 2, 2026 | Award | 50,000 | $6.09 | $304.5K | 50.0K | Form 4 ↗ |
Lester Rachael Chief Business Officer | Feb 2, 2026 | Award | 50,000 | — | — | 50.0K | Form 4 ↗ |
Lester Rachael Chief Business Officer | Feb 2, 2026 | Award | 20,000 | — | — | 20.0K | Form 4 ↗ |
Chu Yu-Waye Chief Medical Officer | Feb 2, 2026 | Award | 300,000 | $6.09 | $1.83M | 300.0K | Form 4 ↗ |
Chu Yu-Waye Chief Medical Officer | Feb 2, 2026 | Award | 75,000 | — | — | 210.7K | Form 4 ↗ |
BELVIN MARCIA SVP, Chief Scientific Officer | Feb 2, 2026 | Award | 60,000 | — | — | 332.3K | Form 4 ↗ |
Source: /insider-trading/search (FMP stable). Buy/Sell direction: acquisitionOrDisposition A=Buy, D=Sell. RSU vesting (M-Exempt) excluded from sentiment bar. All data from SEC EDGAR public filings.
About institutional & insider ownership
CytomX Therapeutics, Inc. (CTMX) is primarily owned by institutional investors, who hold approximately 28.1% of total shares outstanding. Company insiders own approximately 13.00%, while retail and public investors account for the remaining 58.85%.
The largest institutional shareholder of CytomX Therapeutics, Inc. is TANG CAPITAL MANAGEMENT LLC, holding approximately 6.72 million shares — equal to 7.71% of outstanding shares — as of March 31, 2025.
A total of 67 institutional investors currently hold CTMX stock, with a combined institutional value of approximately $28,811,696 as of the most recent 13F filing period.
Frequently asked questions
CTMX ownershipCytomX Therapeutics, Inc. (CTMX) is primarily owned by institutional investors, who hold approximately 28.1% of shares. The largest shareholder is TANG CAPITAL MANAGEMENT LLC with a 7.71% stake. Company insiders hold 13.00%. Data sourced from SEC Form 13F as of March 31, 2025.