Mark Sullivan

CIK 1331843 · Chief Legal Officer · last filed 2026-06-26

Mark Sullivan is a Chief Legal Officer who has filed 34 SEC Form 4 insider transactions across 4 companies since 2011. The most recent filing shows the insider sold $585.8K of DFTX on Jun 26, 2026. Across all open-market trades the lifetime net is −$1.5M, making them a net seller over the disclosed history. Current disclosed insider exposure totals $14.2M 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

$14.23M

Companies

4

Total Filings

34

Lifetime Open-Market Net

-$1.55M

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 320,571 $44.39 $14.23M -$783.4K 4 2026-06-26
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 19,186 $12.58 $241.3K -$152.1K 6 2023-03-06
MModal Inc. (MEDH) Delisted Gen Counsel, CCO & Secretary 39,268 -$43.7K 5 2012-01-04

Recent Filings

34 filings
Insider activity across all companies, newest first. Form 4 rows are post-trade confirmations (buys, sells, grants, exercises). Notice (144) rows are pre-trade notices of intent to sell restricted or control stock under Rule 144 — they may not all execute. Compare adjacent dates to see which notices became actual sales.
Filed Symbol Action Net Shares Net $ Link
2026-06-26 DFTX Sell (S) −13,008 -$585.8K EDGAR
2026-06-25 DFTX Notice (144) −13,008 -$548.0K EDGAR
2026-06-22 DFTX Grant (A) +62,500 $0 EDGAR
2026-03-26 DFTX Sell (S) −10,702 -$197.7K EDGAR
2026-03-25 DFTX Notice (144) −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
2025-12-29 DFTX Notice (144) −11,276 -$148.2K EDGAR
2025-09-26 Definium Therapeutics, Inc. (MNMD) Delisted Sell (S) −11,278 -$110.2K EDGAR
2025-09-25 DFTX Notice (144) −11,278 -$110.2K EDGAR
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Form 4 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.
Notice (144 / 144/A): Form 144 is a notice of intent to sell restricted/control stock under Rule 144, filed before the sale; 144/A is an amendment. Many notices are pre-scheduled under Rule 10b5-1 plans. A Form 4 with code S typically follows within a few days when the planned sale executes; missing follow-up Form 4s suggest the notice was cancelled or modified.