# Siren, L.L.C.

> Institutional holdings reported to the SEC as of Q2 2026 on Form 13F. CIK 2005245. Source: https://holderbook.com/funds/2005245-siren-l-l-c/

- Reported value: $4.9B
- Positions: 116
- Weight of the ten largest: 44.6%
- Filed: 2026-08-13

A 13F reports long US equity positions only. Short positions, bonds, foreign listings, private holdings and cash are not visible, so this is not the manager's whole book.

## Holdings

| Security | Ticker | Value | Shares | Weight | Quarters held |
|---|---|---|---|---|---|
| SCHOLAR ROCK HLDG CORP | [SRRK](https://holderbook.com/stocks/SRRK/) | $526.6M | 9,575,013 | 10.7% | 8 |
| KYMERA THERAPEUTICS INC | [KYMR](https://holderbook.com/stocks/KYMR/) | $336.7M | 2,935,830 | 6.8% | 8 |
| ERASCA INC | [ERAS](https://holderbook.com/stocks/ERAS/) | $208.8M | 11,397,781 | 4.2% | 8 |
| VERADERMICS INC | [MANE](https://holderbook.com/stocks/MANE/) | $203.5M | 1,655,374 | 4.1% | 2 |
| TANGO THERAPEUTICS INC | [TNGX](https://holderbook.com/stocks/TNGX/) | $193.2M | 6,179,364 | 3.9% | 8 |
| REVOLUTION MEDICINES INC | [RVMD](https://holderbook.com/stocks/RVMD/) | $168.6M | 900,000 | 3.4% | 8 |
| BICARA THERAPEUTICS INC | [BCAX](https://holderbook.com/stocks/BCAX/) | $166.4M | 5,602,970 | 3.4% | 8 |
| ARROWHEAD PHARMACEUTICALS IN | [ARWR](https://holderbook.com/stocks/ARWR/) | $139.8M | 1,715,476 | 2.8% | 8 |
| BEONE MEDICINES LTD | [ONC](https://holderbook.com/stocks/ONC/) | $132.5M | 465,000 | 2.7% | 8 |
| EDGEWISE THERAPEUTICS INC | [EWTX](https://holderbook.com/stocks/EWTX/) | $129.4M | 3,184,629 | 2.6% | 8 |
| RHYTHM PHARMACEUTICALS INC | [RYTM](https://holderbook.com/stocks/RYTM/) | $126.2M | 1,136,275 | 2.6% | 6 |
| LEXICON PHARMACEUTICALS INC | [LXRX](https://holderbook.com/stocks/LXRX/) | $106.3M | 44,303,518 | 2.2% | 8 |
| ENLIVEN THERAPEUTICS INC | [ELVN](https://holderbook.com/stocks/ELVN/) | $90.1M | 1,774,411 | 1.8% | 2 |
| SPYRE THERAPEUTICS INC | [SYRE](https://holderbook.com/stocks/SYRE/) | $86.0M | 968,598 | 1.7% | 7 |
| PARABILIS MEDICINES INC | [PBLS](https://holderbook.com/stocks/PBLS/) | $81.9M | 2,992,259 | 1.7% | 1 |
| XENON PHARMACEUTICALS INC | [XENE](https://holderbook.com/stocks/XENE/) | $79.6M | 1,318,564 | 1.6% | 8 |
| SOLID BIOSCIENCES INC | [SLDB](https://holderbook.com/stocks/SLDB/) | $76.8M | 7,690,405 | 1.6% | 8 |
| ABIVAX SA | [ABVX](https://holderbook.com/stocks/ABVX/) | $76.8M | 576,000 | 1.6% | 1 |
| HEMAB THERAPEUTICS HLDGS INC | - | $76.6M | 2,086,834 | 1.6% | 1 |
| ARCUS BIOSCIENCES INC | [RCUS](https://holderbook.com/stocks/RCUS/) | $74.6M | 2,420,430 | 1.5% | 8 |
| COGENT BIOSCIENCES INC | [COGT](https://holderbook.com/stocks/COGT/) | $72.0M | 1,859,279 | 1.5% | 5 |
| RELAY THERAPEUTICS INC | [RLAY](https://holderbook.com/stocks/RLAY/) | $68.3M | 3,650,000 | 1.4% | 1 |
| TAYSHA GENE THERAPIES INC | [TSHA](https://holderbook.com/stocks/TSHA/) | $67.1M | 9,846,579 | 1.4% | 8 |
| DEFINIUM THERAPEUTICS INC | [DFTX](https://holderbook.com/stocks/DFTX/) | $66.8M | 1,419,493 | 1.4% | 2 |
| STOKE THERAPEUTICS INC | [STOK](https://holderbook.com/stocks/STOK/) | $65.3M | 1,995,347 | 1.3% | 7 |
| DISC MEDICINE INC | [IRON](https://holderbook.com/stocks/IRON/) | $65.0M | 888,401 | 1.3% | 6 |
| CYTOKINETICS INC | [CYTK](https://holderbook.com/stocks/CYTK/) | $64.7M | 758,952 | 1.3% | 2 |
| SEPTERNA INC | [SEPN](https://holderbook.com/stocks/SEPN/) | $63.6M | 1,900,000 | 1.3% | 7 |
| OLEMA PHARMACEUTICALS INC | [OLMA](https://holderbook.com/stocks/OLMA/) | $60.8M | 4,856,949 | 1.2% | 3 |
| CRINETICS PHARMACEUTICALS IN | [CRNX](https://holderbook.com/stocks/CRNX/) | $53.2M | 1,420,788 | 1.1% | 8 |
| KAILERA THERAPEUTICS INC | [KLRA](https://holderbook.com/stocks/KLRA/) | $48.8M | 2,214,286 | 1.0% | 1 |
| DYNE THERAPEUTICS INC | [DYN](https://holderbook.com/stocks/DYN/) | $47.3M | 2,129,125 | 1.0% | 8 |
| STRUCTURE THERAPEUTICS INC | [GPCR](https://holderbook.com/stocks/GPCR/) | $46.9M | 872,967 | 0.9% | 4 |
| TABOOLA.COM LTD | [TBLA](https://holderbook.com/stocks/TBLA/) | $42.1M | 8,423,410 | 0.9% | 8 |
| PALVELLA THERAPEUTICS INC NE | [PVLA](https://holderbook.com/stocks/PVLA/) | $39.3M | 257,485 | 0.8% | 3 |
| SILENCE THERAPEUTICS PLC | [SLN](https://holderbook.com/stocks/SLN/) | $36.4M | 3,311,438 | 0.7% | 8 |
| DENALI THERAPEUTICS INC | [DNLI](https://holderbook.com/stocks/DNLI/) | $35.9M | 1,396,513 | 0.7% | 8 |
| REMITLY GLOBAL INC | [RELY](https://holderbook.com/stocks/RELY/) | $34.6M | 1,543,271 | 0.7% | 8 |
| CULLINAN THERAPEUTICS INC | [CGEM](https://holderbook.com/stocks/CGEM/) | $34.5M | 1,893,410 | 0.7% | 8 |
| CAPITAL ONE FINL CORP | [COF](https://holderbook.com/stocks/COF/) | $34.4M | 171,615 | 0.7% | 1 |
| TREVI THERAPEUTICS INC | [TRVI](https://holderbook.com/stocks/TRVI/) | $33.3M | 1,786,867 | 0.7% | 7 |
| ORIC PHARMACEUTICALS INC | [ORIC](https://holderbook.com/stocks/ORIC/) | $32.5M | 2,998,192 | 0.7% | 8 |
| ALPHABET INC | [GOOGL](https://holderbook.com/stocks/GOOGL/) | $32.2M | 90,000 | 0.7% | 8 |
| DBV TECHNOLOGIES S A | [DBVT](https://holderbook.com/stocks/DBVT/) | $30.5M | 1,857,362 | 0.6% | 3 |
| ABSCI CORPORATION | [ABSI](https://holderbook.com/stocks/ABSI/) | $28.7M | 2,474,764 | 0.6% | 2 |
| SIONNA THERAPEUTICS INC | [SION](https://holderbook.com/stocks/SION/) | $26.9M | 610,515 | 0.5% | 6 |
| RAPPORT THERAPEUTICS INC | [RAPP](https://holderbook.com/stocks/RAPP/) | $26.7M | 641,469 | 0.5% | 8 |
| AMYLYX PHARMACEUTICALS INC | [AMLX](https://holderbook.com/stocks/AMLX/) | $26.6M | 1,480,586 | 0.5% | 2 |
| ANNEXON INC | [ANNX](https://holderbook.com/stocks/ANNX/) | $25.5M | 4,458,646 | 0.5% | 2 |
| MONOPAR THERAPEUTICS INC | [MNPR](https://holderbook.com/stocks/MNPR/) | $25.0M | 270,118 | 0.5% | 3 |
| ORUKA THERAPEUTICS INC | [ORKA](https://holderbook.com/stocks/ORKA/) | $23.8M | 250,000 | 0.5% | 1 |
| SEAPORT THERAPEUTICS INC | [SPTX](https://holderbook.com/stocks/SPTX/) | $23.8M | 1,095,316 | 0.5% | 1 |
| DAMORA THERAPEUTICS INC | [DMRA](https://holderbook.com/stocks/DMRA/) | $23.4M | 900,000 | 0.5% | 2 |
| TYRA BIOSCIENCES INC | [TYRA](https://holderbook.com/stocks/TYRA/) | $23.2M | 725,000 | 0.5% | 1 |
| MICROSOFT CORP | [MSFT](https://holderbook.com/stocks/MSFT/) | $22.9M | 37,500 | 0.5% | 8 |
| ZURA BIO LTD | [ZURA](https://holderbook.com/stocks/ZURA/) | $22.0M | 3,734,866 | 0.4% | 3 |
| TAIWAN SEMICONDUCTOR MANUFAC | [TSM](https://holderbook.com/stocks/TSM/) | $21.3M | 44,700 | 0.4% | 8 |
| NVIDIA CORPORATION | [NVDA](https://holderbook.com/stocks/NVDA/) | $19.0M | 95,000 | 0.4% | 8 |
| REZOLUTE INC | [RZLT](https://holderbook.com/stocks/RZLT/) | $17.3M | 3,328,287 | 0.4% | 2 |
| MAPLIGHT THERAPEUTICS INC | [MPLT](https://holderbook.com/stocks/MPLT/) | $16.1M | 450,000 | 0.3% | 3 |
| NEUMORA THERAPEUTICS INC. | [NMRA](https://holderbook.com/stocks/NMRA/) | $14.4M | 8,497,822 | 0.3% | 8 |
| NEBIUS GROUP N.V. | [NBIS](https://holderbook.com/stocks/NBIS/) | $14.4M | 52,000 | 0.3% | 7 |
| CYTOMX THERAPEUTICS INC | [CTMX](https://holderbook.com/stocks/CTMX/) | $13.0M | 3,457,711 | 0.3% | 2 |
| GENERATE BIOMEDICINES INC | [GENB](https://holderbook.com/stocks/GENB/) | $12.4M | 736,104 | 0.3% | 2 |
| INHIBIKASE THERAPEUTICS INC | [IKT](https://holderbook.com/stocks/IKT/) | $11.9M | 5,850,000 | 0.2% | 3 |
| ADAGENE INC | [ADAG](https://holderbook.com/stocks/ADAG/) | $11.2M | 2,666,666 | 0.2% | 1 |
| Engene Therapeutics Inc | [ENGN](https://holderbook.com/stocks/ENGN/) | $10.8M | 6,256,662 | 0.2% | 1 |
| WHITEHAWK THERAPEUTICS INC | [WHWK](https://holderbook.com/stocks/WHWK/) | $10.7M | 2,337,102 | 0.2% | 6 |
| DATADOG INC | [DDOG](https://holderbook.com/stocks/DDOG/) | $10.4M | 40,000 | 0.2% | 8 |
| SERVICENOW INC | [NOW](https://holderbook.com/stocks/NOW/) | $9.9M | 100,000 | 0.2% | 8 |
| BROADCOM INC | [AVGO](https://holderbook.com/stocks/AVGO/) | $9.4M | 25,000 | 0.2% | 3 |
| IONQ INC | [IONQ](https://holderbook.com/stocks/IONQ/) | $9.1M | 170,000 | 0.2% | 8 |
| JFROG LTD | [FROG](https://holderbook.com/stocks/FROG/) | $8.7M | 95,500 | 0.2% | 8 |
| OCULIS HOLDING AG | [OCS](https://holderbook.com/stocks/OCS/) | $8.7M | 625,000 | 0.2% | 1 |
| IREN LIMITED | [IREN](https://holderbook.com/stocks/IREN/) | $8.0M | 175,000 | 0.2% | 4 |
| AMAZON COM INC | [AMZN](https://holderbook.com/stocks/AMZN/) | $7.7M | 32,500 | 0.2% | 8 |
| CROWDSTRIKE HLDGS INC | [CRWD](https://holderbook.com/stocks/CRWD/) | $7.6M | 10,000 | 0.2% | 8 |
| DESIGN THERAPEUTICS INC | [DSGN](https://holderbook.com/stocks/DSGN/) | $7.6M | 523,212 | 0.2% | 1 |
| PDD HOLDINGS INC | [PDD](https://holderbook.com/stocks/PDD/) | $7.2M | 95,000 | 0.1% | 8 |
| SATELLOS BIOSCIENCE INC | [MSLE](https://holderbook.com/stocks/MSLE/) | $6.9M | 892,074 | 0.1% | 2 |
| DYNATRACE INC | [DT](https://holderbook.com/stocks/DT/) | $6.8M | 155,000 | 0.1% | 8 |
| APPLE INC | [AAPL](https://holderbook.com/stocks/AAPL/) | $6.7M | 0 | 0.1% | 1 |
| TENAX THERAPEUTICS INC | [TENX](https://holderbook.com/stocks/TENX/) | $6.2M | 427,141 | 0.1% | 4 |
| VTV THERAPEUTICS INC | [VTVT](https://holderbook.com/stocks/VTVT/) | $6.1M | 163,000 | 0.1% | 4 |
| ELOXX PHARMACEUTICALS INC | - | $5.6M | 400,000 | 0.1% | 1 |
| AGOMAB THERAPEUTICS NV | [AGMB](https://holderbook.com/stocks/AGMB/) | $5.3M | 411,250 | 0.1% | 2 |
| ALIBABA GROUP HLDG LTD | [BABA](https://holderbook.com/stocks/BABA/) | $4.8M | 50,000 | 0.1% | 1 |
| KORRO BIO INC | [KRRO](https://holderbook.com/stocks/KRRO/) | $4.6M | 347,718 | 0.1% | 8 |
| CELLEBRITE DI LTD | [CLBT](https://holderbook.com/stocks/CLBT/) | $4.5M | 311,544 | 0.1% | 5 |
| INVIVYD INC | [IVVD](https://holderbook.com/stocks/IVVD/) | $4.4M | 5,000,000 | 0.1% | 3 |
| OUSTER INC | [OUST](https://holderbook.com/stocks/OUST/) | $4.2M | 67,500 | 0.1% | 1 |
| PALISADE BIO INC | [PALI](https://holderbook.com/stocks/PALI/) | $4.2M | 2,000,000 | 0.1% | 1 |
| AEVA TECHNOLOGIES INC | [AEVA](https://holderbook.com/stocks/AEVA/) | $4.2M | 145,459 | 0.1% | 2 |
| SEER INC | [SEER](https://holderbook.com/stocks/SEER/) | $4.1M | 2,458,673 | 0.1% | 8 |
| NOVABRIDGE BIOSCIENCES | [NBP](https://holderbook.com/stocks/NBP/) | $3.9M | 2,004,739 | 0.1% | 4 |
| GITLAB INC | [GTLB](https://holderbook.com/stocks/GTLB/) | $3.8M | 125,000 | 0.1% | 5 |
| ODYSSEY THERAPEUTICS INC | [ODTX](https://holderbook.com/stocks/ODTX/) | $3.7M | 200,000 | 0.1% | 1 |
| FOGHORN THERAPEUTICS INC | [FHTX](https://holderbook.com/stocks/FHTX/) | $3.5M | 720,720 | 0.1% | 8 |
| AGENUS INC | [AGEN](https://holderbook.com/stocks/AGEN/) | $3.3M | 1,064,250 | 0.1% | 6 |
| MONDAY COM LTD | [MNDY](https://holderbook.com/stocks/MNDY/) | $3.1M | 42,500 | 0.1% | 4 |

## What the disclosed book did

Not the fund's return. This is the change in value of the positions disclosed on Form 13F, had they been left untouched, against SPY over the same quarter ends.

| Quarter | Book | Market | Difference | Priced |
|---|---|---|---|---|
| Q2 2026 | +27.4% | +14.8% | +12.6% | 99% |
| Q1 2026 | +8.1% | -4.6% | +12.7% | 98% |
| Q4 2025 | +22.5% | +2.4% | +20.2% | 100% |
| Q3 2025 | +30.0% | +7.8% | +22.1% | 100% |
| Q2 2025 | +11.2% | +10.5% | +0.7% | 100% |
| Q1 2025 | -21.9% | -4.6% | -17.3% | 100% |
| Q4 2024 | +5.9% | +2.1% | +3.7% | 98% |

## Quarter by quarter

| Quarter | Value | Positions |
|---|---|---|
| Q2 2026 | $4.9B | 116 |
| Q1 2026 | $3.6B | 100 |
| Q4 2025 | $3.4B | 113 |
| Q3 2025 | $2.6B | 115 |
| Q2 2025 | $1.9B | 110 |
| Q1 2025 | $1.8B | 116 |
| Q4 2024 | $2.3B | 117 |
| Q3 2024 | $2.0B | 110 |