Joseph S Zakrzewski

CIK 1331852 · Chief Executive Officer · last filed 2026-03-23

Joseph S Zakrzewski is a Chief Executive Officer who has filed 107 SEC Form 4 insider transactions across 6 companies since 2008. The most recent filing, for ANTX, was dated Mar 23, 2026. Across all open-market trades the lifetime net is −$51.9M, making them a net seller over the disclosed history. Current disclosed insider exposure totals $10.2M across reported positions.

"Disclosed insider exposure" sums this person's most-recently-reported share counts across each company they're an insider in, multiplied by the current underlying price. It is not net worth — it misses retail holdings, private investments, real estate, index funds, and any company where the person isn't an SEC-reporting insider. For informational purposes only.

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Disclosed Exposure

$10.18M

Companies

6

Total Filings

107

Lifetime Open-Market Net

-$51.93M

Holdings By Company

Latest on-record share count from this person's most recent non-derivative Form 4 transaction in each company. Disclosed exposure = shares × current underlying price.
Symbol Role Shares Price Disclosed Exposure Lifetime OM Net Filings Latest Filed
ANTX Director 551,418 $4.74 $2.61M -$1.88M 12 2026-03-23
Cyteir Therapeutics, Inc. (CYT) Delisted Director 376,490 $3.02 $1.14M $176.6K 11 2024-02-08
SANGAMO THERAPEUTICS, INC (SGMO) Delisted Director 60,700 $0.18 $10.8K $147.9K 9 2022-03-01
AMRN Director 196,547 $15.24 $3.00M -$45.96M 38 2021-12-16
ACCELERON PHARMA INC (XLRN) Delisted Director 0 $178.75 $0 -$2.46M 15 2021-11-22
PODD Director 30,558 $149.70 $4.57M -$1.95M 12 2017-05-18

Recent Filings

107 filings
Form 4 transactions across all companies, newest first.
Filed Symbol Action Net Shares Net $ Link
2026-03-23 ANTX Mixed $0 EDGAR
2026-02-23 ANTX Grant (A) $0 EDGAR
2025-05-23 ANTX Grant (A) $0 EDGAR
2025-04-11 ANTX Grant (A) +10,523 $0 EDGAR
2024-12-23 ANTX Grant (A) +9,816 $0 EDGAR
2024-11-27 ANTX Buy (P) +2,000 $2.8K EDGAR
2024-11-20 ANTX Buy (P) +25,000 $25.0K EDGAR
2024-06-21 ANTX Grant (A) $0 EDGAR
2024-02-08 Cyteir Therapeutics, Inc. (CYT) Delisted Exer (M) +14,150 $23.9K EDGAR
2024-01-19 ANTX Sell (S) −100,000 -$1.91M EDGAR
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Codes: P = open-market purchase · S = open-market sale · A = grant/award · M = option exercise · F = tax withholding at vest · G = bona-fide gift · D = disposition to issuer · J = other (see filing footnote). Only P / S codes carry directional signal.