RYTM
Rhythm Pharmaceuticals, Inc. · Healthcare · Biotechnology
Momentum inputs (comparable managers): holder breadth 0.0% · share flow -1.3% · net new positions 0.0% — formula
All ownership figures: tracked 13F managers only, common-stock positions, reporting period Q4 2024
| 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 ✦ | 6.57M | -8.9% | $367.86M | 0.3% | ▼ Trim | 3 | SEC ↗ |
| 2 | State Street Global Advisors ✦ (passive) | 1.84M | — | $103.05M | 0.0% | n/c | 1 | SEC ↗ |
| 3 | Geode Capital Management ✦ (passive) | 1.26M | 0.0% | $70.32M | 0.0% | ▼ Trim | 3 | SEC ↗ |
| 4 | Geode Capital Management ✦ (passive) | 1.26M | 0.0% | $70.32M | 0.0% | ▼ Trim | 3 | SEC ↗ |
| 5 | Marshall Wace ✦ | 692.80K | +70.4% | $38.78M | 0.0% | ▲ Add | 3 | SEC ↗ |
| 6 | Marshall Wace ✦ | 692.80K | +70.4% | $38.78M | 0.0% | ▲ Add | 3 | SEC ↗ |
| 7 | Marshall Wace ✦ | 692.80K | +70.4% | $38.78M | 0.0% | ▲ Add | 3 | SEC ↗ |
| 8 | T. Rowe Price ✦ | 685.15K | +24.4% | $38.35M | 0.0% | ▲ Add | 3 | SEC ↗ |
| 9 | T. Rowe Price ✦ | 685.15K | +24.4% | $38.35M | 0.0% | ▲ Add | 3 | SEC ↗ |
| 10 | Norges Bank ✦ (passive) | 205.65K | +210.3% | $11.51M | 0.0% | ▲ Add | 3 | SEC ↗ |
| 11 | D. E. Shaw & Co. ✦ | 48.20K | +1022.5% | $2.70M | 0.0% | ▲ Add | 2 | SEC ↗ |
| 12 | Citadel Advisors ✦ | 40.42K | -60.7% | $2.26M | 0.0% | ▼ Trim | 2 | SEC ↗ |
| 13 | Wellington Management ✦ | 25.55K | -7.8% | $1.43M | 0.0% | ▼ Trim | 3 | SEC ↗ |
| 14 | Wellington Management ✦ | 25.55K | -7.8% | $1.43M | 0.0% | ▼ Trim | 3 | SEC ↗ |
| 15 | Wellington Management ✦ | 25.55K | -7.8% | $1.43M | 0.0% | ▼ Trim | 3 | SEC ↗ |
| 16 | Wellington Management ✦ | 25.55K | -7.8% | $1.43M | 0.0% | ▼ Trim | 3 | SEC ↗ |
| 17 | AQR Capital Management ✦ | 15.86K | -51.7% | $887,675 | 0.0% | ▼ Trim | 3 | SEC ↗ |
| 18 | AQR Capital Management ✦ | 15.86K | -51.7% | $887,675 | 0.0% | ▼ Trim | 3 | SEC ↗ |
| 19 | AQR Capital Management ✦ | 15.86K | -51.7% | $887,675 | 0.0% | ▼ Trim | 3 | SEC ↗ |
| 20 | Millennium Management ✦ | 15.26K | -58.7% | $854,199 | 0.0% | ▼ Trim | 2 | SEC ↗ |
| 21 | Gotham Asset Management ✦ | 6.79K | -28.4% | $379,880 | 0.0% | ▼ Trim | 3 | SEC ↗ |
“Their weight” = the position's share of that manager's reported 13F equity value — the conviction measure. ✦ = curated manager.
New buyers
| No new tracked buyers this quarter. |
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