IRON
Disc Medicine, Inc. · Healthcare · Biotechnology
Momentum inputs (comparable managers):
holder breadth +21.4% ·
share flow +12.8% ·
net new positions +17.6%
· formula
Broad accumulation: rising shares across more holders
All ownership figures: tracked 13F managers only, common-stock positions, reporting period Q3 2025
| Quarter | Holders | Δ | Shares | Reported value | New | Exits |
|---|---|---|---|---|---|---|
| Q3 2026 | 1 | 0 | 1.12M | $73.28M | n/a | −1 |
| 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) ✦ | 4.94M | +52.0% | $326.12M | 0.0% | ▲ Add | 2 | SEC ↗ ×4 |
| 2 | BlackRock ✦ (passive) | 2.02M | -1.2% | $133.43M | 0.0% | ▼ Trim | 2 | SEC ↗ ×13 |
| 3 | JPMorgan Chase ✦ | 1.51M | n/a | $99.50M | 0.0% | n/c | 1 | SEC ↗ ×8 |
| 4 | The Vanguard Group ✦ (passive) | 1.45M | +3.7% | $95.69M | 0.0% | ▲ Add | 2 | SEC ↗ ×5 |
| 5 | Wellington Management ✦ | 1.41M | -1.5% | $93.18M | 0.0% | ▼ Trim | 6 | SEC ↗ ×8 |
| 6 | T. Rowe Price ✦ | 1.33M | -12.5% | $87.65M | 0.0% | ▼ Trim | 6 | SEC ↗ ×2 |
| 7 | State Street Global Advisors ✦ (passive) | 1.05M | +12.5% | $69.09M | 0.0% | ▲ Add | 4 | SEC ↗ |
| 8 | Geode Capital Management ✦ (passive) | 628.15K | +4.9% | $41.52M | 0.0% | ▲ Add | 6 | SEC ↗ ×2 |
| 9 | Goldman Sachs Group ✦ | 529.08K | n/a | $34.96M | 0.0% | n/c | 1 | SEC ↗ ×2 |
| 10 | Adage Capital Partners ✦ | 450.00K | 0.0% | $29.74M | 0.0% | Held | 6 | SEC ↗ |
| 11 | Millennium Management ✦ | 161.00K | +645.6% | $10.64M | 0.0% | ▲ Add | 4 | SEC ↗ |
| 12 | Morgan Stanley ✦ | 56.08K | n/a | $3.71M | 0.0% | n/c | 1 | SEC ↗ ×7 |
| 13 | Citadel Advisors ✦ | 50.39K | New | $3.33M | 0.0% | New | 1 | SEC ↗ |
| 14 | Marshall Wace ✦ | 14.00K | New | $925,186 | 0.0% | New | 1 | SEC ↗ |
| 15 | AQR Capital Management ✦ | 13.98K | +2.4% | $923,666 | 0.0% | ▲ Add | 2 | SEC ↗ ×4 |
| 16 | Point72 Asset Management ✦ | 9.23K | New | $609,627 | 0.0% | New | 1 | SEC ↗ |
| 17 | Renaissance Technologies ✦ | 6.80K | -93.0% | $449,344 | 0.0% | ▼ Trim | 4 | SEC ↗ |
“Their weight” = the position's share of that manager's reported 13F equity value: the conviction measure. ✦ = curated manager.
New buyers
| Citadel Advisors | $3.33M | 0.0% |
| Marshall Wace | $925,186 | 0.0% |
| Point72 Asset Management | $609,627 | 0.0% |
Exited
| No tracked exits this quarter. |
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 · 266 sh · $21,341
Director · 11.47K sh · $920,238
Director · 13.78K sh · $1.11M
Director · 2.87K sh · $229,377
Director · 55 sh · $4,397
Director · 2.39K sh · $190,921
Director · 5.94K sh · $474,782
Director · 115 sh · $9,197
Director · 4.94K sh · $395,212
Director · 27.14K sh · $1.90M
Awards, exercises and tax withholding are never counted as buys or sales here. Methodology