Siren, L.L.C.
- SEC CIK
- 0002005245
- Latest filing
- Aug 13, 2026
Holdings in Q2 2026
Holdings as of Jun 30, 2026, filed Aug 13, 2026. Long positions only; changes compare share counts with Q1 2026.
- Positions
- 115
- +15 vs. Q1 2026
- Portfolio value
- $4.93B
- +$1.32B (+36.5%) vs. Q1 2026
| Security | Class | Shares | Value | % of portfolio | Share change | Action | History |
|---|---|---|---|---|---|---|---|
| SRRKScholar Rock Holding Corp | COM | 9,575,013 | $526.6M | 10.7% | −1,250,000−11.5% | Reduced | History |
| KYMRKymera Therapeutics, Inc. | COM | 2,935,830 | $336.7M | 6.8% | −251,000−7.9% | Reduced | History |
| ERASErasca, Inc. | COM | 11,397,781 | $208.8M | 4.2% | +153,535+1.4% | Added | History |
| MANEVeradermics, Inc | COMMON STOCK | 1,655,374 | $203.5M | 4.1% | +150,000+10.0% | Added | History |
| TNGXTango Therapeutics, Inc. | COM | 6,179,364 | $193.2M | 3.9% | +522,259+9.2% | Added | History |
| RVMDRevolution Medicines, Inc. | COM | 900,000 | $168.6M | 3.4% | −210,980−19.0% | Reduced | History |
| BCAXBicara Therapeutics Inc. | COM | 5,602,970 | $166.4M | 3.4% | −200,000−3.4% | Reduced | History |
| ARWRArrowhead Pharmaceuticals, Inc. | COM | 1,715,476 | $139.8M | 2.8% | +100,000+6.2% | Added | History |
| ONCBeOne Medicines Ltd. | ADR | 465,000 | $132.5M | 2.7% | 00.0% | Unchanged | History |
| EWTXEdgewise Therapeutics, Inc. | COM | 3,184,629 | $129.4M | 2.6% | −1,245,634−28.1% | Reduced | History |
| RYTMRhythm Pharmaceuticals, Inc. | COM | 1,136,275 | $126.2M | 2.6% | +410,764+56.6% | Added | History |
| LXRXLexicon Pharmaceuticals, Inc. | COM NEW | 44,303,518 | $106.3M | 2.2% | 00.0% | Unchanged | History |
| ELVNEnliven Therapeutics, Inc. | COM | 1,774,411 | $90.1M | 1.8% | +1,028,185+137.8% | Added | History |
| SYRESpyre Therapeutics, Inc. | COM NEW | 968,598 | $86.0M | 1.7% | +150,000+18.3% | Added | History |
| PBLSParabilis Medicines, Inc. | Stock | 2,992,259 | $81.9M | 1.7% | +2,992,259 | New | History |
| XENEXenon Pharmaceuticals Inc. | COM | 1,318,564 | $79.6M | 1.6% | 00.0% | Unchanged | History |
| SLDBSolid Biosciences Inc. | COM NEW | 7,690,405 | $76.8M | 1.6% | 00.0% | Unchanged | History |
| ABVXAbivax S.A. | SPONSORED ADS | 576,000 | $76.8M | 1.6% | +576,000 | New | History |
| COAGHemab Therapeutics Holdings, Inc. | COM SHS | 2,086,834 | $76.6M | 1.6% | +2,086,834 | New | History |
| RCUSArcus Biosciences, Inc. | COM | 2,420,430 | $74.6M | 1.5% | −586,647−19.5% | Reduced | History |
| COGTCogent Biosciences, Inc. | COM | 1,859,279 | $72.0M | 1.5% | +150,000+8.8% | Added | History |
| RLAYRelay Therapeutics, Inc. | COM | 3,650,000 | $68.3M | 1.4% | +3,650,000 | New | History |
| TSHATaysha Gene Therapies, Inc. | COM SHS | 9,846,579 | $67.1M | 1.4% | +1,016,666+11.5% | Added | History |
| DFTXDefinium Therapeutics, Inc. | COM SHS | 1,419,493 | $66.8M | 1.4% | +500,000+54.4% | Added | History |
| STOKStoke Therapeutics, Inc. | COM | 1,995,347 | $65.3M | 1.3% | 00.0% | Unchanged | History |
| IRONDisc Medicine, Inc. | COM | 888,401 | $65.0M | 1.3% | −100,000−10.1% | Reduced | History |
| CYTKCytokinetics Inc | COM NEW | 758,952 | $64.7M | 1.3% | +145,000+23.6% | Added | History |
| SEPNSepterna, Inc. | COM | 1,900,000 | $63.6M | 1.3% | −100,000−5.0% | Reduced | History |
| OLMAOlema Pharmaceuticals, Inc. | COM | 4,856,949 | $60.8M | 1.2% | +100,000+2.1% | Added | History |
| CRNXCrinetics Pharmaceuticals, Inc. | COM | 1,420,788 | $53.2M | 1.1% | −482,848−25.4% | Reduced | History |
| KLRAKailera Therapeutics, Inc. | COMMON STOCK | 2,214,286 | $48.8M | 1.0% | +2,214,286 | New | History |
| DYNDyne Therapeutics, Inc. | COM | 2,129,125 | $47.3M | 1.0% | −100,000−4.5% | Reduced | History |
| GPCRStructure Therapeutics Inc. | SPONSORED ADS | 872,967 | $46.9M | 1.0% | −455,731−34.3% | Reduced | History |
| TBLATaboola.com Ltd. | ORD SHS | 8,423,410 | $42.1M | 0.9% | −1,546,085−15.5% | Reduced | History |
| PVLAPalvella Therapeutics, Inc. | COM | 257,485 | $39.3M | 0.8% | 00.0% | Unchanged | History |
| SLNSilence Therapeutics plc | ADS | 3,311,438 | $36.4M | 0.7% | +400,000+13.7% | Added | History |
| DNLIDenali Therapeutics Inc. | COM | 1,396,513 | $35.9M | 0.7% | 00.0% | Unchanged | History |
| RELYRemitly Global, Inc. | COM | 1,543,271 | $34.6M | 0.7% | 00.0% | Unchanged | History |
| CGEMCullinan Therapeutics, Inc. | COM | 1,893,410 | $34.5M | 0.7% | +700,000+58.7% | Added | History |
| COFCapital One Financial Corp | Stock | 171,615 | $34.4M | 0.7% | +171,615 | New | History |
| TRVITrevi Therapeutics, Inc. | COM | 1,786,867 | $33.3M | 0.7% | 00.0% | Unchanged | History |
| ORICOric Pharmaceuticals, Inc. | COM | 2,998,192 | $32.5M | 0.7% | 00.0% | Unchanged | History |
| GOOGLAlphabet Inc. | Stock | 90,000 | $32.2M | 0.7% | +24,297+37.0% | Added | History |
| DBVTDBV Technologies S.A. | SPONSORED ADS | 1,857,362 | $30.5M | 0.6% | 00.0% | Unchanged | History |
| ABSIAbsci Corp | COM | 2,474,764 | $28.7M | 0.6% | +674,764+37.5% | Added | History |
| SIONSionna Therapeutics, Inc. | COM | 610,515 | $26.9M | 0.5% | +310,515+103.5% | Added | History |
| RAPPRapport Therapeutics, Inc. | COM | 641,469 | $26.7M | 0.5% | 00.0% | Unchanged | History |
| AMLXAmylyx Pharmaceuticals, Inc. | COM | 1,480,586 | $26.6M | 0.5% | +250,586+20.4% | Added | History |
| ANNXAnnexon, Inc. | COM | 4,458,646 | $25.5M | 0.5% | +500,000+12.6% | Added | History |
| MNPRMonopar Therapeutics | COM NEW | 270,118 | $25.0M | 0.5% | 00.0% | Unchanged | History |
| ORKAOruka Therapeutics, Inc. | COM | 250,000 | $23.8M | 0.5% | +250,000 | New | History |
| SPTXSeaport Therapeutics, Inc. | COMMON STOCK | 1,095,316 | $23.8M | 0.5% | +1,095,316 | New | History |
| DMRADamora Therapeutics, Inc. | COM NEW | 900,000 | $23.4M | 0.5% | 00.0% | Unchanged | History |
| TYRATyra Biosciences, Inc. | COM | 725,000 | $23.2M | 0.5% | +725,000 | New | History |
| ZURAZura Bio Ltd | CLASS A ORD SHS | 3,734,866 | $22.0M | 0.4% | 00.0% | Unchanged | History |
| TSMTaiwan Semiconductor Manufacturing Co Ltd | ADR | 44,700 | $21.3M | 0.4% | +2,500+5.9% | Added | History |
| NVDANVIDIA Corp | Stock | 95,000 | $19.0M | 0.4% | +5,915+6.6% | Added | History |
| RZLTRezolute, Inc. | COM NEW | 3,328,287 | $17.3M | 0.4% | 00.0% | Unchanged | History |
| MPLTMapLight Therapeutics, Inc. | COM | 450,000 | $16.1M | 0.3% | 00.0% | Unchanged | History |
| NMRANeumora Therapeutics, Inc. | COM | 8,497,822 | $14.4M | 0.3% | 00.0% | Unchanged | History |
| NBISNebius Group N.V. | Stock | 52,000 | $14.4M | 0.3% | −61,614−54.2% | Reduced | History |
| MSFTMicrosoft Corp | Stock | 37,500 | $14.0M | 0.3% | −3,880−9.4% | Reduced | History |
| CTMXCytomX Therapeutics, Inc. | COM | 3,457,711 | $13.0M | 0.3% | 00.0% | Unchanged | History |
| GENBGenerate Biomedicines, Inc. | COM SHS | 736,104 | $12.4M | 0.3% | 00.0% | Unchanged | History |
| IKTInhibikase Therapeutics, Inc. | COM NEW | 5,850,000 | $11.9M | 0.2% | 00.0% | Unchanged | History |
| ADAGAdagene Inc. | ADS | 2,666,666 | $11.2M | 0.2% | +2,666,666 | New | History |
| ENGNenGene Therapeutics Inc. | COM | 6,256,662 | $10.8M | 0.2% | +1,003,503+19.1% | Added | History |
| WHWKWhitehawk Therapeutics, Inc. | COM | 2,337,102 | $10.7M | 0.2% | +255,102+12.3% | Added | History |
| DDOGDatadog, Inc. | CL A COM | 40,000 | $10.4M | 0.2% | −14,300−26.3% | Reduced | History |
| NOWServiceNow, Inc. | Stock | 100,000 | $9.93M | 0.2% | +12,910+14.8% | Added | History |
| AVGOBroadcom Inc. | Stock | 25,000 | $9.44M | 0.2% | +10,000+66.7% | Added | History |
| IONQIonQ, Inc. | COM | 170,000 | $9.05M | 0.2% | 00.0% | Unchanged | History |
| FROGJFrog Ltd | Stock | 95,500 | $8.68M | 0.2% | −33,316−25.9% | Reduced | History |
| OCSOculis Holding AG | ORDINARY SHARES | 625,000 | $8.67M | 0.2% | +625,000 | New | History |
| IRENIREN Ltd | ORDINARY SHARES | 175,000 | $8.00M | 0.2% | +131,900+306.0% | Added | History |
| AMZNAmazon Com Inc | Stock | 32,500 | $7.75M | 0.2% | −14,141−30.3% | Reduced | History |
| CRWDCrowdStrike Holdings, Inc. | Stock | 10,000 | $7.63M | 0.2% | −13,070−56.7% | Reduced | History |
| DSGNDesign Therapeutics, Inc. | COM | 523,212 | $7.57M | 0.2% | +523,212 | New | History |
| PDDPDD Holdings Inc. | SPONSORED ADS | 95,000 | $7.25M | 0.1% | +11,599+13.9% | Added | History |
| MSLESatellos Bioscience Inc. | COM | 892,074 | $6.94M | 0.1% | 00.0% | Unchanged | History |
| DTDynatrace, Inc. | Stock | 155,000 | $6.81M | 0.1% | +5,000+3.3% | Added | History |
| TENXTenax Therapeutics, Inc. | COM NEW | 427,141 | $6.21M | 0.1% | 00.0% | Unchanged | History |
| VTVTvTv Therapeutics Inc. | CL A NEW | 163,000 | $6.14M | 0.1% | 00.0% | Unchanged | History |
| ELOXEloxx Pharmaceuticals, Inc. | COM NEW | 400,000 | $5.55M | 0.1% | +400,000 | New | History |
| AGMBAgomAb Therapeutics NV | SPONSORED ADS | 411,250 | $5.34M | 0.1% | 00.0% | Unchanged | History |
| BABAAlibaba Group Holding Ltd | ADR | 50,000 | $4.80M | 0.1% | +50,000 | New | History |
| KRROKorro Bio, Inc. | COM | 347,718 | $4.58M | 0.1% | 00.0% | Unchanged | History |
| CLBTCellebrite DI Ltd. | ORDINARY SHARES | 311,544 | $4.55M | 0.1% | 00.0% | Unchanged | History |
| IVVDInvivyd, Inc. | COM | 5,000,000 | $4.36M | 0.1% | +1,000,000+25.0% | Added | History |
| OUSTOuster, Inc. | COM NEW | 67,500 | $4.22M | 0.1% | +67,500 | New | History |
| PALIPalisade Bio, Inc. | COM | 2,000,000 | $4.18M | 0.1% | +2,000,000 | New | History |
| AEVAAeva Technologies, Inc. | COM NEW | 145,459 | $4.18M | 0.1% | +35,459+32.2% | Added | History |
| SEERSeer, Inc. | COM CL A | 2,458,673 | $4.08M | 0.1% | 00.0% | Unchanged | History |
| NBPNovaBridge Biosciences | SPONSORED ADS | 2,004,739 | $3.91M | 0.1% | −995,261−33.2% | Reduced | History |
| GTLBGitlab Inc. | CLASS A COM | 125,000 | $3.82M | 0.1% | +25,000+25.0% | Added | History |
| ODTXOdyssey Therapeutics, Inc. | COMMON STOCK | 200,000 | $3.74M | 0.1% | +200,000 | New | History |
| FHTXFoghorn Therapeutics Inc. | COM | 720,720 | $3.52M | 0.1% | 00.0% | Unchanged | History |
| AGENAgenus Inc | COM NEW | 1,064,250 | $3.26M | 0.1% | 00.0% | Unchanged | History |
| MNDYmonday.com Ltd. | SHS | 42,500 | $3.08M | 0.1% | +17,500+70.0% | Added | History |
| ZTSZoetis Inc. | Stock | 35,000 | $2.52M | 0.1% | +35,000 | New | History |
Options (2)
Puts and calls in the same filing. Amounts are the market value of the underlying shares, which is what 13F reports.
Sold out since Q1 2026 (9)
Positions held at the end of Q1 2026 that are gone from this filing.
| Security | Class | Shares in Q1 2026 | Value in Q1 2026 | % of portfolio in Q1 2026 | History |
|---|---|---|---|---|---|
| CNTACentessa Pharmaceuticals plc | SPONSORED ADS | 1,053,464 | $41.8M | 1.2% | History |
| FULCFulcrum Therapeutics, Inc. | COM | 2,350,000 | $18.0M | 0.5% | History |
| WVEWave Life Sciences, Inc. | SHS | 2,450,000 | $17.8M | 0.5% | History |
| QUREuniQure N.V. | SHS | 1,000,000 | $16.4M | 0.5% | History |
| BCYCBicycle Therapeutics PLC | SPONSORED ADS | 1,560,882 | $7.24M | 0.2% | History |
| FPSForgent Power Solutions, Inc. | COM SHS CL A | 100,000 | $2.93M | 0.1% | History |
| MUMicron Technology Inc | Stock | 6,000 | $2.03M | 0.1% | History |
| ASAmer Sports, Inc. | COM SHS | 50,000 | $1.65M | <0.1% | History |
| PRMBPrimo Brands Corp | CLASS A COM SHS | 50,000 | $941.5K | <0.1% | History |