DFTX · Insider Trading
Definium Therapeutics, Inc. Common Shares
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.
| Filed | Insider | Role | Type | Shares | Value |
|---|---|---|---|---|---|
| 2026-09-29 | Brandi Roberts | Chief Financial Officer | Sell | −3,377 | −$123.50K |
| 2026-09-29 | Robert Barrow | Chief Executive Officer | Sell | −31,550 | −$1.15M |
| 2026-09-29 | Daniel Karlin | Chief Medical Officer | Sell | −10,853 | −$396.89K |
| 2026-09-29 | Mark Sullivan | Chief Legal Officer | Sell | −14,051 | −$513.85K |
| 2026-09-29 | Matthew T. Wiley | Chief Commercial Officer | Sell | −3,097 | −$113.26K |
| 2026-09-18 | Andreas Krebs | Director | M | +1,629 | +$57.86K |
| 2026-09-18 | Carol A Vallone | Director | M | +1,086 | +$38.57K |
| 2026-09-14 | Matthew T. Wiley | Chief Commercial Officer | A | +125,000 | — |
| 2026-09-14 | Brandi Roberts | Chief Financial Officer | A | +125,000 | — |
| 2026-09-14 | Mark Sullivan | Chief Legal Officer | A | +125,000 | — |
| 2026-09-14 | Robert Barrow | Chief Executive Officer | A | +750,000 | — |
| 2026-09-14 | Daniel Karlin | Chief Medical Officer | A | +200,000 | — |
| 2026-09-04 | Robert Barrow | Chief Executive Officer | MIXED | +20,977 | −$721.73K |
| 2026-08-12 | Matthew T. Wiley | Chief Commercial Officer | A | +62,500 | — |
| 2026-08-12 | Brandi Roberts | Chief Financial Officer | A | +62,500 | — |
| 2026-08-12 | Mark Sullivan | Chief Legal Officer | A | +62,500 | — |
| 2026-08-12 | Robert Barrow | Chief Executive Officer | A | +375,000 | — |
| 2026-08-12 | Daniel Karlin | Chief Medical Officer | A | +100,000 | — |
| 2026-06-26 | Daniel Karlin | Chief Medical Officer | Sell | −10,035 | −$451.88K |
| 2026-06-26 | Mark Sullivan | Chief Legal Officer | Sell | −13,008 | −$585.75K |
| 2026-06-26 | Matthew T. Wiley | Chief Commercial Officer | Sell | −2,867 | −$129.10K |
| 2026-06-26 | Robert Barrow | Chief Executive Officer | Sell | −29,208 | −$1.32M |
| 2026-06-26 | Brandi Roberts | Chief Financial Officer | Sell | −3,013 | −$135.68K |
| 2026-06-22 | Daniel Karlin | Chief Medical Officer | A | +100,000 | — |
| 2026-06-22 | Mark Sullivan | Chief Legal Officer | A | +62,500 | — |
| 2026-06-22 | Matthew T. Wiley | Chief Commercial Officer | A | +62,500 | — |
| 2026-06-22 | Brandi Roberts | Chief Financial Officer | A | +62,500 | — |
| 2026-06-22 | Robert Barrow | Chief Executive Officer | A | +375,000 | — |
| 2026-06-15 | Andreas Krebs | Director | A | +4,666 | — |
| 2026-06-15 | Roger Crystal | Director | A | +4,666 | — |
| 2026-06-15 | Carol A Vallone | Director | A | +4,666 | — |
| 2026-06-15 | Roger Adsett | Director | A | +3,555 | — |
| 2026-06-15 | Suzanne Louise Bruhn | Director | A | +4,666 | — |
| 2026-06-15 | David W Gryska | Director | A | +4,666 | — |
| 2026-03-26 | Daniel Karlin | Chief Medical Officer | Sell | −8,018 | −$148.09K |
| 2026-03-26 | Robert Barrow | Chief Executive Officer | Sell | −24,431 | −$451.24K |
| 2026-03-26 | Mark Sullivan | Chief Legal Officer | Sell | −10,702 | −$197.67K |
| 2026-02-05 | Brandi Roberts | Chief Financial Officer | A | +150,000 | — |
| 2026-02-05 | Robert Barrow | Chief Executive Officer | A | +320,000 | — |
| 2026-02-05 | Mark Sullivan | Chief Legal Officer | A | +125,000 | — |
| 2026-02-05 | Daniel Karlin | Chief Medical Officer | A | +150,000 | — |
| 2026-02-05 | Matthew T. Wiley | Chief Commercial Officer | A | +115,000 | — |
| 2026-01-29 | Roger Adsett | Director | A | +50,000 deriv. | — |
| Insider | Role | Shares Held | Value |
|---|---|---|---|
| Robert Barrow | Chief Executive Officer | 2,213,090 | $72.97M |
| Daniel Karlin | Chief Medical Officer | 792,846 | $26.14M |
| Mark Sullivan | Chief Legal Officer | 494,228 | $16.29M |
| Brandi Roberts | Chief Financial Officer | 394,528 | $13.01M |
| Matthew T. Wiley | Chief Commercial Officer | 359,036 | $11.84M |
| Suzanne Louise Bruhn | Director | 24,289 | $800.81K |
| Roger Crystal | Director | 24,289 | $800.81K |
| Carol A Vallone | Director | 22,296 | $735.10K |
| Andreas Krebs | Director | 21,402 | $705.62K |
| David W Gryska | Director | 19,900 | $656.10K |
| Roger Adsett | Director | 3,555 | $117.21K |
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.
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.