Rhythm Pharmaceuticals
RYTM
279 hedge funds and large institutions have $7.8B invested in Rhythm Pharmaceuticals in 2025 Q4 according to their latest regulatory filings, with 57 funds opening new positions, 106 increasing their positions, 89 reducing their positions, and 40 closing their positions.
43% more first-time investments, than exits
New positions opened: 57 | Existing positions closed: 40
41% more call options, than puts
Call options by funds: $45.9M | Put options by funds: $32.5M
19% more repeat investments, than reductions
Existing positions increased: 106 | Existing positions reduced: 89
8% more capital invested
Capital invested by funds: $7.2B → $7.8B (+$598M)
6% more funds holding
Funds holding: 264 → 279 (+15)
2.45% more ownership
Funds ownership: 106.73% → 109.17% (+2.4%)
0% more funds holding in top 10
Funds holding in top 10: 10 → 10 (0)
Top Buyers
Top Sellers
| 1 |
Alkeon Capital Management
New York
|
-$103M |
| 2 |
Primecap Management
Pasadena,
California
|
-$83.2M |
| 3 |
Fidelity Investments
Boston,
Massachusetts
|
-$46.6M |
| 4 |
Voloridge Investment Management
Jupiter,
Florida
|
-$32.6M |
| 5 |
Balyasny Asset Management
Chicago,
Illinois
|
-$29.5M |
RYTM Hedge Fund Activity: Q4 2025 in Review
279 of the 8,223 institutional investors tracked by Wall St. Rank reported a position in Rhythm Pharmaceuticals (RYTM) for Q4 2025, worth a combined $7.8B — up 8.3% from $7.2B a quarter earlier.
Buyers outnumbered sellers: 57 funds opened new RYTM positions and 40 closed out — a net gain of 17 holders — while 106 added to existing stakes and 89 trimmed.
The largest buyer was Vanguard Group, adding an estimated $129M. The largest seller was Alkeon Capital Management, exiting entirely with an estimated $103M sold.
- 279 institutional investors held Rhythm Pharmaceuticals (RYTM) as of Q4 2025, up from 264 in Q3 2025.
- Funds reported $7.8B of Rhythm Pharmaceuticals stock for Q4 2025, up 8.3% quarter-over-quarter.
- 57 funds opened new Rhythm Pharmaceuticals positions in Q4 2025 and 40 closed out, a net change of +17 holders.
- The largest Rhythm Pharmaceuticals buyer in Q4 2025 was Vanguard Group, an estimated $129M added.
- The largest Rhythm Pharmaceuticals seller in Q4 2025 was Alkeon Capital Management, an estimated $103M sold.
Based on aggregated 13F filings for Q4 2025.