CytomX Therapeutics CTMX Insider Ownership

NASDAQ CTMX
$2.75 +0.06 (+2.23%)
At close: Sep 29, 2026 · 4:00 PM EDT

Insider Holdings by Owner

3.35Mn Shares

Insider Ownership Statistics

as of 30 Sep, 2026
Insider Ownership
1.53%
▲+0.046% pp QoQ
Shares Held by Insiders
3.35Mn
filed for Sep 2026
▲+3.08% QoQ
Shares Outstanding
218.94Mn
218,939,423 shares
Direct Holdings
3.35Mn
Indirect: 0
Net Shares Traded (QoQ)
+100.00K
net buying in Sep 2026
Insiders Holding Shares
12
with Form 4 holdings on file

Shares Owned by Insiders

Shares held % of outstanding
Latest —
Average ownership —
Peak ownership —

Shares Purchased/Sold by Insiders

Bought Sold
Latest quarter —
Net over range —
Buying quarters —

Insider Ownership Summary

Quarter ending 30 Sep, 2026

CytomX Therapeutics's top three insider shareholders as of September 29, 2026 are Sean A. Mccarthy (Ceo, 1.08Mn shares), Sean A. Mccarthy (Ceo, 987.89K shares), Marcia Belvin (Svp, Chief Scientific Officer, 300.76K shares).

Form 4 Holdings

Insiders Holding CTMX

Insiders 12
Shares held 3.35Mn
Of outstanding 1.53%
# Insider Position Direct Indirect Total Share of Insiders Last Filed
1 Sean A. Mccarthy Ceo 2,066,813 0 2,066,813 61.8% 19 Mar, 2026
2 Marcia Belvin Svp, Chief Scientific Officer 300,760 0 300,760 9.0% 19 Mar, 2026
3 Christopher Ogden Chief Financial Officer 295,324 0 295,324 8.8% 17 Jun, 2026
4 Yu-Waye Chu Chief Medical Officer 189,446 0 189,446 5.7% 19 Mar, 2026
5 Lloyd A Rowland General Counsel 120,594 0 120,594 3.6% 20 Mar, 2025
6 Jeffrey B Landau Chief Business Officer 119,056 0 119,056 3.6% 22 Aug, 2024
7 Alejandra Carvajal Chief Legal Officer 100,000 0 100,000 3.0% 05 Aug, 2026
8 Amy C. Peterson Evp, Chief Development Officer 58,433 0 58,433 1.7% 20 Mar, 2023
9 Carlos Campoy Chief Financial Officer 38,224 0 38,224 1.1% 20 Mar, 2023
10 Alison L. Hannah Chief Medical Officer 31,898 0 31,898 1.0% 21 Jul, 2022
11 Rachael Lester Chief Business Officer 20,000 0 20,000 0.6% 04 Feb, 2026
12 Elaine V Jones Director 5,142 0 5,142 0.2% 31 Mar, 2023

Each row is that insider’s most recently reported position, from Form 4 filings over the last 60 months — which is why this total does not tie to the quarterly series above, where a quarter counts only the insiders who filed in it. Shares held through a fund or institutional portfolio are counted on the institutional ownership page instead.

Form 4 Filings

634 Insider Transactions

Source SEC Form 4
Latest quarter Sep 2026
Download Data
Date Insider Position Transaction Shares Price Value Shares Held After Ownership
03 Aug, 2026 Alejandra Carvajal Chief Legal Officer Acquired A 100,000 $0.00 $0 100,000 Direct
03 Aug, 2026 Alejandra Carvajal Chief Legal Officer Acquired A 450,000 $0.00 $0 450,000 Direct
24 Jul, 2026 Charles S. Fuchs Director Acquired A 118,000 $0.00 $0 118,000 Direct
17 Jun, 2026 Zhen Su Director Acquired A 59,000 $0.00 $0 59,000 Direct
17 Jun, 2026 Elaine V Jones Director Acquired A 59,000 $0.00 $0 59,000 Direct
17 Jun, 2026 Alan Ashworth Director Acquired A 59,000 $0.00 $0 59,000 Direct
17 Jun, 2026 Matthew P. Young Director Acquired A 59,000 $0.00 $0 59,000 Direct
17 Jun, 2026 James R Meyers Director Acquired A 59,000 $0.00 $0 59,000 Direct
17 Jun, 2026 Halley E Gilbert Director Acquired A 59,000 $0.00 $0 59,000 Direct
17 Jun, 2026 Mani Mohindru Director Acquired A 59,000 $0.00 $0 59,000 Direct
15 Jun, 2026 Christopher Ogden Chief Financial Officer Disposed S 1,624 $3.05 $4.95K 295,324 Direct
17 Mar, 2026 Yu-Waye Chu Chief Medical Officer Disposed S 21,279 $6.42 $136.68K 189,446 Direct
17 Mar, 2026 Sean A. Mccarthy Ceo Disposed S 118,969 $6.42 $764.14K 1,078,922 Direct
17 Mar, 2026 Marcia Belvin Svp, Chief Scientific Officer Disposed S 31,492 $6.42 $202.27K 300,760 Direct
17 Mar, 2026 Christopher Ogden Chief Financial Officer Disposed S 19,323 $6.42 $124.11K 296,948 Direct
02 Feb, 2026 Christopher Ogden Chief Financial Officer Acquired A 90,000 $0.00 $0 316,271 Direct
02 Feb, 2026 Sean A. Mccarthy Ceo Acquired A 210,000 $0.00 $0 1,197,891 Direct
02 Feb, 2026 Rachael Lester Chief Business Officer Acquired A 20,000 $0.00 $0 20,000 Direct
02 Feb, 2026 Yu-Waye Chu Chief Medical Officer Acquired A 75,000 $0.00 $0 210,725 Direct
02 Feb, 2026 Marcia Belvin Svp, Chief Scientific Officer Acquired A 60,000 $0.00 $0 332,252 Direct