Mark Sullivan

CIK 1331843 · Chief Legal Officer · last filed 2026-03-26

Mark Sullivan is a Chief Legal Officer who has filed 23 SEC Form 4 insider transactions across 4 companies since 2011. The most recent filing shows the insider sold $197.7K of DFTX on Mar 26, 2026. Across all open-market trades the lifetime net is −$963.3K, making them a net seller over the disclosed history. Current disclosed insider exposure totals $6.7M 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

$6.71M

Companies

4

Total Filings

23

Lifetime Open-Market Net

-$963.3K

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
DFTX Chief Legal Officer 271,079 $24.75 $6.71M -$197.7K 2 2026-03-26
Definium Therapeutics, Inc. (MNMD) Delisted Chief Legal Officer 282,576 $15.00 $4.24M -$569.9K 10 2025-12-29
Carisma Therapeutics Inc. (SESN) Delisted General Counsel & Secretary 383,716 $12.58 $4.83M -$152.1K 6 2023-03-06
MModal Inc. (MEDH) Delisted Gen Counsel, CCO & Secretary 39,268 -$43.7K 5 2012-01-04

Recent Filings

23 filings
Form 4 transactions across all companies, newest first.
Filed Symbol Action Net Shares Net $ Link
2026-03-26 DFTX Sell (S) −10,702 -$197.7K EDGAR
2026-02-05 DFTX Grant (A) +125,000 $0 EDGAR
2025-12-29 Definium Therapeutics, Inc. (MNMD) Delisted Sell (S) −11,276 -$148.2K EDGAR
2025-09-26 Definium Therapeutics, Inc. (MNMD) Delisted Sell (S) −11,278 -$110.2K EDGAR
2025-06-26 Definium Therapeutics, Inc. (MNMD) Delisted Sell (S) −11,491 -$78.1K EDGAR
2025-03-26 Definium Therapeutics, Inc. (MNMD) Delisted Sell (S) −6,576 -$44.3K EDGAR
2025-03-13 Definium Therapeutics, Inc. (MNMD) Delisted Grant (A) +150,000 $0 EDGAR
2024-12-27 Definium Therapeutics, Inc. (MNMD) Delisted Sell (S) −4,519 -$33.6K EDGAR
2024-09-25 Definium Therapeutics, Inc. (MNMD) Delisted Sell (S) −4,430 -$26.5K EDGAR
2024-06-25 Definium Therapeutics, Inc. (MNMD) Delisted Sell (S) −17,854 -$128.9K 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.