DFTX (Definium Therapeutics, Inc. Common Shares)

Insider Trading Activity

Every open-market purchase and sale reported by DFTX officers, directors and 10%+ beneficial owners on SEC Form 4, which must be filed within two business days of the transaction. Sales often reflect scheduled 10b5-1 plans or tax withholding rather than a directional view, so read counts alongside the size and the filer.

Market data may be delayed, incomplete, or inaccurate. Not a recommendation to buy, sell, or hold any security. Verify quotes with your broker before trading. See Terms §17.

Form 4 Filings
30
most recent
Open-Market Buys
0
code P
Sales
8
code S
Reporting Insiders
11
current holders
DFTX — Recent Form 4 Transactions (latest 2026-08-12)
FiledInsiderRole TypeSharesValue
2026-08-12 Matthew T. Wiley Chief Commercial Officer A
2026-08-12 Brandi Roberts Chief Financial Officer A
2026-08-12 Mark Sullivan Chief Legal Officer A
2026-08-12 Robert Barrow Chief Executive Officer A
2026-08-12 Daniel Karlin Chief Medical Officer A
2026-06-26 Daniel Karlin Chief Medical Officer Sell
2026-06-26 Mark Sullivan Chief Legal Officer Sell
2026-06-26 Matthew T. Wiley Chief Commercial Officer Sell
2026-06-26 Robert Barrow Chief Executive Officer Sell
2026-06-26 Brandi Roberts Chief Financial Officer Sell
2026-06-22 Daniel Karlin Chief Medical Officer A
2026-06-22 Mark Sullivan Chief Legal Officer A
2026-06-22 Matthew T. Wiley Chief Commercial Officer A
2026-06-22 Brandi Roberts Chief Financial Officer A
2026-06-22 Robert Barrow Chief Executive Officer A
2026-06-15 Andreas Krebs Director A
2026-06-15 ROGER CRYSTAL Director A
2026-06-15 Carol A Vallone Director A
2026-06-15 Roger Adsett Director A
2026-06-15 Suzanne Louise Bruhn Director A
2026-06-15 DAVID W GRYSKA Director A
2026-03-26 Daniel Karlin Chief Medical Officer Sell
2026-03-26 Robert Barrow Chief Executive Officer Sell
2026-03-26 Mark Sullivan Chief Legal Officer Sell
2026-02-05 Brandi Roberts Chief Financial Officer A
2026-02-05 Robert Barrow Chief Executive Officer A
2026-02-05 Mark Sullivan Chief Legal Officer A
2026-02-05 Daniel Karlin Chief Medical Officer A
2026-02-05 Matthew T. Wiley Chief Commercial Officer A
2026-01-29 Roger Adsett Director A
DFTX — Current Insider Holders
InsiderRole Shares HeldValue
Chief Executive Officer 1,473,246
Chief Medical Officer 603,282
Chief Legal Officer 383,071
Chief Financial Officer 271,987
Chief Commercial Officer 237,133
Director 24,289
Director 24,289
Director 21,210
Director 19,900
Director 19,773
Director 3,555
How to read Form 4 activity

Form 4 reports a change in beneficial ownership by an officer, director or 10%+ holder, and must be filed within two business days of the transaction — so this is close to real time, unlike the 45-day-lagged 13F institutional data.

Transaction codes matter more than the raw buy/sell count. Code P is an open-market purchase — an insider choosing to buy with their own money, which is the signal most research treats as informative. Code S is a sale, but sales are frequently pre-scheduled under a 10b5-1 plan or cover tax withholding on vesting equity, so a run of sales often says nothing directional. Codes A and M are grants and option exercises rather than open-market decisions.

Full filing history and per-insider positions are on the DFTX quote page; the site-wide leaderboard is on the insider transactions hub.