Siren, L.L.C.
CIK: 0002005245Latest portfolio: $3.4B · Q4 2025
Holdings
113
Total Value
$3.4B
New Positions
26
Closed Positions
28
Top Holdings
View All 113 Holdings →| # | Stock | Shares | Value | % Portfolio | Change | Type |
|---|---|---|---|---|---|---|
| 1 | SRRKScholar Rock Holding Corp | 10,825,013 | $476.8M | 14.22% | +1.6M | |
| 2 | KYMRKymera Therapeutics Inc | 3,286,830 | $255.7M | 7.63% | -141,320 | |
| 3 | ONCBeOne Medicines AG | 500,000 | $151.9M | 4.53% | +7K | |
| 4 | EWTXEdgewise Therapeutics Inc | 4,529,990 | $112.4M | 3.35% | +633K | |
| 5 | RVMDRevolution Medicines Inc | 1,335,075 | $106.3M | 3.17% | +291K | |
| 6 | CNTACentessa Pharmaceuticals PLC | 4,027,517 | $100.7M | 3.00% | +800K | |
| 7 | ARWRArrowhead Pharmaceuticals Inc | 1,500,476 | $99.6M | 2.97% | -1,169,404 | |
| 8 | BCAXBicara Therapeutics Inc | 5,216,969 | $87.8M | 2.62% | — | |
| 9 | OLMAOlema Pharmaceuticals Inc | 3,300,700 | $82.5M | 2.46% | NEW | |
| 10 | IRONDisc Medicine Inc | 988,401 | $78.5M | 2.34% | +75K | |
| 11 | GPCRStructure Therapeutics Inc | 1,078,698 | $75.0M | 2.24% | +52K | |
| 12 | TNGXTango Therapeutics Inc | 8,165,374 | $72.3M | 2.16% | +2.3M | |
| 13 | RCUSArcus Biosciences Inc | 3,007,077 | $71.7M | 2.14% | +95K | |
| 14 | STOKStoke Therapeutics Inc | 2,247,347 | $71.3M | 2.13% | — | |
| 15 | CRNXCrinetics Pharmaceuticals Inc | 1,507,636 | $70.2M | 2.09% | -180,975 | |
| 16 | DYNDyne Therapeutics Inc | 3,502,941 | $68.5M | 2.04% | -1,226,233 | |
| 17 | APLSApellis Pharmaceuticals Inc | 2,578,396 | $64.8M | 1.93% | — | |
| 18 | COGTCogent Biosciences Inc | 1,629,279 | $57.9M | 1.73% | -95,000 | |
| 19 | SEPNSepterna Inc | 2,000,000 | $55.8M | 1.66% | -202,514 | |
| 20 | TSHATaysha Gene Therapies Inc | 10,129,913 | $55.7M | 1.66% | -884,824 | |
| 21 | RYTMRhythm Pharmaceuticals Inc | 499,975 | $53.5M | 1.60% | — | |
| 22 | ASNDAscendis Pharma A/S | 235,862 | $50.3M | 1.50% | — | |
| 23 | RAPTRAPT Therapeutics Inc | 1,375,000 | $46.6M | 1.39% | +795K | |
| 24 | TBLATaboola.com Ltd | 9,969,495 | $46.0M | 1.37% | — | |
| 25 | LXRXLexicon Pharmaceuticals Inc | 38,918,903 | $44.8M | 1.34% | — |
Quarterly Changes
New Positions
Increased Positions
Sector Breakdown
HealthcareNaN% ($InfinityT)
Technology0.0% ($2.233284177734763e+86T)
Communication Services0.0% ($4595917587648.1T)
Unknown0.0% ($1071.3T)
Consumer Cyclical0.0% ($118.9T)
Real Estate0.0% ($2.3M)
Financial Services0.0% ($1.6M)
Consumer Defensive0.0% ($1.2M)
Filing History
Fund Information
Siren, L.L.C. is an institutional investment manager that files 13F reports with the SEC. As of the Q4 2025 filing, the fund reported a portfolio valued at $3.4B across 113 holdings. The largest position is Scholar Rock Holding Corp (SRRK), representing 14.2% of the portfolio. Compared to the previous quarter, the fund opened 26 new positions and closed 28 positions. 13F filings are required quarterly disclosures that provide transparency into the holdings of institutional investment managers with at least $100 million in qualifying assets.