RYTM
Rhythm Pharmaceuticals, Inc. · Healthcare · Biotechnology
Momentum inputs (comparable managers):
holder breadth +16.7% ·
share flow +1.0% ·
net new positions +14.3%
— formula
Broad accumulation — rising shares across more holders
All ownership figures: tracked 13F managers only, common-stock positions, reporting period Q1 2025
| Quarter | Holders | Δ | Shares | Reported value | New | Exits |
|---|---|---|---|---|---|---|
| Q2 2026 | 113 | +6 | 44.38M | $4.90B | +14 | −7 |
| Q1 2026 | 109 | +6 | 41.83M | $3.64B | +11 | −6 |
| Q4 2025 | 102 | 0 | 43.14M | $4.62B | +3 | −2 |
| Q3 2025 | 20 | +1 | 28.88M | $2.92B | +2 | −2 |
| Q2 2025 | 17 | 0 | 22.96M | $1.45B | +1 | −1 |
| Q1 2025 | 14 | +2 | 11.52M | $610.22M | +2 | — |
| Q4 2024 | 12 | 0 | 11.40M | $638.39M | — | — |
| Q3 2024 | 11 | +3 | 9.71M | $508.75M | +3 | — |
| Q2 2024 | 8 | — | 9.56M | $392.54M | — | — |
| # | Manager | Shares | Δ shares | Value | Their weight | Held | ||
|---|---|---|---|---|---|---|---|---|
| 1 | PRIMECAP Management ✦ | 5.79M | -11.9% | $306.55M | 0.3% | ▼ Trim | 4 | SEC ↗ |
| 2 | State Street Global Advisors ✦ (passive) | 1.97M | +7.0% | $104.39M | 0.0% | ▲ Add | 2 | SEC ↗ |
| 3 | Geode Capital Management ✦ (passive) | 1.29M | +2.5% | $68.20M | 0.0% | ▲ Add | 4 | SEC ↗ |
| 4 | Geode Capital Management ✦ (passive) | 1.29M | +2.5% | $68.20M | 0.0% | ▲ Add | 4 | SEC ↗ |
| 5 | T. Rowe Price ✦ | 1.20M | +75.0% | $63.52M | 0.0% | ▲ Add | 4 | SEC ↗ |
| 6 | T. Rowe Price ✦ | 1.20M | +75.0% | $63.52M | 0.0% | ▲ Add | 4 | SEC ↗ |
| 7 | Marshall Wace ✦ | 535.10K | -22.8% | $28.34M | 0.0% | ▼ Trim | 4 | SEC ↗ |
| 8 | Marshall Wace ✦ | 535.10K | -22.8% | $28.34M | 0.0% | ▼ Trim | 4 | SEC ↗ |
| 9 | Norges Bank ✦ (passive) | 223.48K | +8.7% | $11.84M | 0.0% | ▲ Add | 4 | SEC ↗ |
| 10 | Millennium Management ✦ | 217.38K | +1324.6% | $11.51M | 0.0% | ▲ Add | 3 | SEC ↗ |
| 11 | D. E. Shaw & Co. ✦ | 83.87K | +74.0% | $4.44M | 0.0% | ▲ Add | 3 | SEC ↗ |
| 12 | D. E. Shaw & Co. ✦ | 83.87K | +74.0% | $4.44M | 0.0% | ▲ Add | 3 | SEC ↗ |
| 13 | Citadel Advisors ✦ | 70.07K | +73.3% | $3.71M | 0.0% | ▲ Add | 3 | SEC ↗ |
| 14 | Citadel Advisors ✦ | 70.07K | +73.3% | $3.71M | 0.0% | ▲ Add | 3 | SEC ↗ |
| 15 | Point72 Asset Management ✦ | 63.84K | New | $3.38M | 0.0% | New | 1 | SEC ↗ |
| 16 | AQR Capital Management ✦ | 39.36K | +148.2% | $2.09M | 0.0% | ▲ Add | 4 | SEC ↗ |
| 17 | AQR Capital Management ✦ | 39.36K | +148.2% | $2.09M | 0.0% | ▲ Add | 4 | SEC ↗ |
| 18 | AQR Capital Management ✦ | 39.36K | +148.2% | $2.09M | 0.0% | ▲ Add | 4 | SEC ↗ |
| 19 | AQR Capital Management ✦ | 39.36K | +148.2% | $2.09M | 0.0% | ▲ Add | 4 | SEC ↗ |
| 20 | AQR Capital Management ✦ | 39.36K | +148.2% | $2.09M | 0.0% | ▲ Add | 4 | SEC ↗ |
| 21 | Wellington Management ✦ | 23.56K | -7.8% | $1.25M | 0.0% | ▼ Trim | 4 | SEC ↗ |
| 22 | Wellington Management ✦ | 23.56K | -7.8% | $1.25M | 0.0% | ▼ Trim | 4 | SEC ↗ |
| 23 | Wellington Management ✦ | 23.56K | -7.8% | $1.25M | 0.0% | ▼ Trim | 4 | SEC ↗ |
| 24 | Wellington Management ✦ | 23.56K | -7.8% | $1.25M | 0.0% | ▼ Trim | 4 | SEC ↗ |
| 25 | Renaissance Technologies ✦ | 14.11K | New | $747,513 | 0.0% | New | 1 | SEC ↗ |
| 26 | Gotham Asset Management ✦ | 4.75K | -30.0% | $251,608 | 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
| Point72 Asset Management | $3.38M | 0.0% |
| Renaissance Technologies | $747,513 | 0.0% |
Exited
| No tracked exits this quarter. |
Full-market context: across ALL 13F filers (SEC structured data, Q1 2026): 284 holders, 72.02M shares, $6.12B 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)
Officer · 2.01K sh · $233,031
Officer · 1.56K sh · $182,170
Officer · 3.40K sh · $402,167
Officer · 800 sh · $95,335
Officer · 75.83K sh · $8.90M
Officer · 2.30K sh · $257,138
Officer · 1.00K sh · $112,856
Officer · 3.60K sh · $413,477
Officer · 14.57K sh · $1.68M
Officer · 18.21K sh · $2.12M
Awards, exercises and tax withholding are never counted as buys or sales here. Methodology