Definium Therapeutics
Develops lysergide and R(-)-MDMA drug candidates for anxiety, depression and autism.
$41.00
After-hours close+0.02 (+0.05%)
At close$40.98(−6.48%)
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Breakdown13F · Form 4
Institutions 91.76%121.80M sharesInsiders 2.43%3.23M sharesOther 5.81%7.72M shares
Shares outstanding 132.74M · Float 128.87M · 97.1% free float
Institutions13F, as of Jun 30, 2026
387 holders · 121.80M shares · 153 new positions · 270 increased · 66 reduced · 35 closed
| Holder | Shares | % outstanding | Chg q/q | Filed |
|---|---|---|---|---|
| BlackRock, Inc. | 11.23M | 8.46% | +2.75M | Aug 7, 2026 |
| Avoro Capital Advisors LLC | 7.19M | 5.42% | +2.19M | Aug 14, 2026 |
| Driehaus Capital Management LLC | 6.85M | 5.16% | +933.4K | Aug 14, 2026 |
| Jupiter Topco LLC | 5.62M | 4.23% | +5.62Mnew | Aug 14, 2026 |
| Capital World Investors | 5.37M | 4.04% | +5.37Mnew | Aug 12, 2026 |
| FMR LLC | 4.75M | 3.58% | +2.94M | Aug 13, 2026 |
| Price T Rowe Associates Inc /MD/ | 4.65M | 3.50% | +4.58M | Aug 14, 2026 |
| Geode Capital Management, LLC | 3.64M | 2.75% | +1.15M | Aug 12, 2026 |
Beneficial owners13D/G · 5% or more, as filed
| Holder | % of class | Shares | Form | Filed |
|---|---|---|---|---|
| BlackRock, Inc. | 8.30% | 6.07M | 13G | Feb 5, 2025 ↗ |
| Commodore Capital LP | 7.20% | 7.43M | 13G | Feb 17, 2026 ↗ |
| Deep Track Capital, LP | 6.87% | 5.50M | 13G | Nov 14, 2025 ↗ |
| Driehaus Capital Management LLC | 6.64% | 6.54M | 13G | Feb 17, 2026 ↗ |
| Avoro Capital Advisors LLC | 5.08% | 5.00M | 13G | Feb 17, 2026 ↗ |
InsidersForm 4
| Insider | Role | Shares | % outstanding | Filed |
|---|---|---|---|---|
| Robert Barrow | director, officer: Chief Executive Officer | 1.47M | 1.11% | Aug 12, 2026 |
| Daniel Karlin | officer: Chief Medical Officer | 603.3K | 0.45% | Aug 12, 2026 |
| Mark Sullivan | officer: Chief Legal Officer | 383.1K | 0.29% | Aug 12, 2026 |
| Brandi Roberts | officer: Chief Financial Officer | 272.0K | 0.20% | Aug 12, 2026 |
| Matthew T. Wiley | officer: Chief Commercial Officer | 237.1K | 0.18% | Aug 12, 2026 |
| Carrie Liao | officer: Chief Accounting Officer | 144.9K | 0.11% | Mar 26, 2025 |
| Suzanne Louise Bruhn | director | 24.3K | 0.02% | Jun 15, 2026 |
| Roger Crystal | director | 24.3K | 0.02% | Jun 15, 2026 |
| Carol A. Vallone | director | 21.2K | 0.02% | Jun 15, 2026 |
| David W. Gryska | director | 19.9K | 0.01% | Jun 15, 2026 |
2 people have not refiled in the last 18 months (413.5K shares), so they are not in the figure above
Latest trades
| Date | Insider | Type | Shares | Avg price | Owned after |
|---|---|---|---|---|---|
| Jun 25, 2026 | Matthew T. Wileyofficer: Chief Commercial Officer | Sale | 2,867 | $45.03 | 174,633 |
| Jun 25, 2026 | Daniel Karlinofficer: Chief Medical Officer | Sale | 10,035 | $45.03 | 503,282 |
| Jun 25, 2026 | Robert Barrowdirector, officer: Chief Executive Officer | Sale | 29,208 | $45.03 | 1,098,246 |
| Jun 25, 2026 | Brandi Robertsofficer: Chief Financial Officer | Sale | 3,013 | $45.03 | 209,487 |
| Jun 25, 2026 | Mark Sullivanofficer: Chief Legal Officer | Sale | 13,008 | $45.03 | 320,571 |
| Mar 25, 2026 | Robert Barrowdirector, officer: Chief Executive Officer | Sale | 24,431 | $18.47 | 752,454 |
| Mar 25, 2026 | Mark Sullivanofficer: Chief Legal Officer | Sale | 10,702 | $18.47 | 271,079 |
| Mar 25, 2026 | Daniel Karlinofficer: Chief Medical Officer | Sale | 8,018 | $18.47 | 413,317 |
| Dec 26, 2025 | Mark Sullivanofficer: Chief Legal Officer | Sale | 11,276 | $13.15 | 282,576 |
| Dec 26, 2025 | Robert Barrowdirector, officer: Chief Executive Officer | Sale | 25,791 | $13.15 | 778,477 |
CongressHouse and Senate disclosures
Not reported.