IRON
Disc Medicine, Inc. · Healthcare · Biotechnology
Momentum inputs (comparable managers):
holder breadth -8.3% ·
share flow -8.0% ·
net new positions -9.1%
· formula
Broad distribution: falling shares and fewer holders
All ownership figures: tracked 13F managers only, common-stock positions, reporting period Q2 2025
| Quarter | Holders | Δ | Shares | Reported value | New | Exits |
|---|---|---|---|---|---|---|
| Q3 2026 | 1 | 0 | 1.12M | $73.28M | n/a | n/a |
| Q2 2026 | 83 | +7 | 22.99M | $1.68B | +9 | −2 |
| Q1 2026 | 79 | +1 | 22.38M | $1.43B | +7 | −6 |
| Q4 2025 | 77 | -1 | 22.10M | $1.75B | +1 | −2 |
| Q3 2025 | 17 | +3 | 15.61M | $1.03B | +3 | n/a |
| Q2 2025 | 11 | -1 | 11.75M | $622.02M | +1 | −2 |
| Q1 2025 | 9 | -1 | 6.07M | $301.51M | n/a | −1 |
| Q4 2024 | 10 | +3 | 5.16M | $327.26M | +3 | n/a |
| Q3 2024 | 6 | -1 | 5.16M | $253.75M | n/a | −1 |
| Q2 2024 | 7 | n/a | 5.00M | $225.18M | n/a | n/a |
| # | Manager | Shares | Δ shares | Value | Their weight | Held | ||
|---|---|---|---|---|---|---|---|---|
| 1 | Fidelity (FMR) ✦ | 3.25M | n/a | $171.89M | 0.0% | n/c | 1 | SEC ↗ ×4 |
| 2 | BlackRock ✦ (passive) | 2.04M | n/a | $108.29M | 0.0% | n/c | 1 | SEC ↗ ×13 |
| 3 | T. Rowe Price ✦ | 1.52M | +11.6% | $80.27M | 0.0% | ▲ Add | 5 | SEC ↗ ×2 |
| 4 | Wellington Management ✦ | 1.43M | -38.9% | $75.84M | 0.0% | ▼ Trim | 5 | SEC ↗ ×7 |
| 5 | The Vanguard Group ✦ (passive) | 1.40M | n/a | $73.97M | 0.0% | n/c | 1 | SEC ↗ ×5 |
| 6 | State Street Global Advisors ✦ (passive) | 929.77K | +1.2% | $49.24M | 0.0% | ▲ Add | 3 | SEC ↗ |
| 7 | Geode Capital Management ✦ (passive) | 598.59K | +4.7% | $31.71M | 0.0% | ▲ Add | 5 | SEC ↗ ×2 |
| 8 | Adage Capital Partners ✦ | 450.00K | +50.0% | $23.83M | 0.0% | ▲ Add | 5 | SEC ↗ |
| 9 | Renaissance Technologies ✦ | 96.42K | -49.6% | $5.11M | 0.0% | ▼ Trim | 3 | SEC ↗ |
| 10 | Millennium Management ✦ | 21.59K | -80.1% | $1.14M | 0.0% | ▼ Trim | 3 | SEC ↗ |
| 11 | AQR Capital Management ✦ | 13.65K | New | $722,851 | 0.0% | New | 1 | SEC ↗ ×4 |
“Their weight” = the position's share of that manager's reported 13F equity value: the conviction measure. ✦ = curated manager.
New buyers
| AQR Capital Management | $722,851 | 0.0% |
Exited
| D. E. Shaw & Co. | $10.90M | was 0.0% |
| Citadel Advisors | $3.09M | was 0.0% |
Full-market context: across ALL 13F filers (SEC structured data, Q1 2026): 203 holders, 40.63M shares, $2.48B reported. This is a different, older period than the tracked-universe figures above and the two are never mixed.
What else this security's tracked holders most often hold: shared-ownership counts, not fundamental relationships.
Open-market purchases (P)
No open-market insider purchases in our coverage window.
Open-market sales (S)
Director · 27.14K sh · $1.90M
Director · 759 sh · $60,690
Director · 18 sh · $1,439
Director · 912 sh · $72,924
Director · 2.34K sh · $187,073
Director · 54 sh · $4,319
Director · 2.81K sh · $224,744
Director · 511 sh · $40,967
Director · 26.54K sh · $2.13M
Director · 22.09K sh · $1.77M
Awards, exercises and tax withholding are never counted as buys or sales here. Methodology