HolderBook

Siren, L.L.C.

Reported holdings as of Q2 2026, from 8 quarterly filings.

CIK
2005245
Reported value
$4.9B
Positions
116
Top 10 weight
44.6%
Filed
2026-08-13
Days after quarter end
44

Holdings

SecurityTickerValue SharesWeightWeight change Held Change
SCHOLAR ROCK HLDG CORPSRRK$526.6M9,575,01310.66%-4.09pp8q-11.5%-$68.8M
KYMERA THERAPEUTICS INCKYMR$336.7M2,935,8306.81%-0.55pp8q-7.9%-$28.8M
ERASCA INCERAS$208.8M11,397,7814.23%-0.82pp8q+1.4%+$2.8M
VERADERMICS INCMANE$203.5M1,655,3744.12%+1.48pp2q+10.0%+$18.4M
TANGO THERAPEUTICS INCTNGX$193.2M6,179,3643.91%+0.63pp8q+9.2%+$16.3M
REVOLUTION MEDICINES INCRVMD$168.6M900,0003.41%+0.42pp8q-19.0%-$39.5M
BICARA THERAPEUTICS INCBCAX$166.4M5,602,9703.37%+0.17pp8q-3.4%-$5.9M
ARROWHEAD PHARMACEUTICALS INARWR$139.8M1,715,4762.83%+0.02pp8q+6.2%+$8.2M
BEONE MEDICINES LTDONC$132.5M465,0002.68%-1.15pp8qHELD
EDGEWISE THERAPEUTICS INCEWTX$129.4M3,184,6292.62%-1.25pp8q-28.1%-$50.6M
RHYTHM PHARMACEUTICALS INCRYTM$126.2M1,136,2752.55%+0.80pp6q+56.6%+$45.6M
LEXICON PHARMACEUTICALS INCLXRX$106.3M44,303,5182.15%+0.24pp8qHELD
ENLIVEN THERAPEUTICS INCELVN$90.1M1,774,4111.82%+1.01pp2q+137.8%+$52.2M
SPYRE THERAPEUTICS INCSYRE$86.0M968,5981.74%+0.60pp7q+18.3%+$13.3M
PARABILIS MEDICINES INCPBLS$81.9M2,992,2591.66%-newNEW
XENON PHARMACEUTICALS INCXENE$79.6M1,318,5641.61%-0.51pp8qHELD
SOLID BIOSCIENCES INCSLDB$76.8M7,690,4051.55%+0.02pp8qHELD
ABIVAX SAABVX$76.8M576,0001.55%-newNEW
HEMAB THERAPEUTICS HLDGS INC$76.6M2,086,8341.55%-newNEW
ARCUS BIOSCIENCES INCRCUS$74.6M2,420,4301.51%-0.29pp8q-19.5%-$18.1M
COGENT BIOSCIENCES INCCOGT$72.0M1,859,2791.46%-0.37pp5q+8.8%+$5.8M
RELAY THERAPEUTICS INCRLAY$68.3M3,650,0001.38%-newNEW
TAYSHA GENE THERAPIES INCTSHA$67.1M9,846,5791.36%+0.26pp8q+11.5%+$6.9M
DEFINIUM THERAPEUTICS INCDFTX$66.8M1,419,4931.35%+0.87pp2q+54.4%+$23.5M
STOKE THERAPEUTICS INCSTOK$65.3M1,995,3471.32%-0.48pp7qHELD
DISC MEDICINE INCIRON$65.0M888,4011.31%-0.44pp6q-10.1%-$7.3M
CYTOKINETICS INCCYTK$64.7M758,9521.31%+0.19pp2q+23.6%+$12.4M
SEPTERNA INCSEPN$63.6M1,900,0001.29%-0.04pp7q-5.0%-$3.3M
OLEMA PHARMACEUTICALS INCOLMA$60.8M4,856,9491.23%-0.74pp3q+2.1%+$1.3M
CRINETICS PHARMACEUTICALS INCRNX$53.2M1,420,7881.08%-0.84pp8q-25.4%-$18.1M
KAILERA THERAPEUTICS INCKLRA$48.8M2,214,2860.99%-newNEW
DYNE THERAPEUTICS INCDYN$47.3M2,129,1250.96%-0.16pp8q-4.5%-$2.2M
STRUCTURE THERAPEUTICS INCGPCR$46.9M872,9670.95%-0.83pp4q-34.3%-$24.5M
TABOOLA.COM LTDTBLA$42.1M8,423,4100.85%flat8q-15.5%-$7.7M
PALVELLA THERAPEUTICS INC NEPVLA$39.3M257,4850.80%-0.09pp3qHELD
SILENCE THERAPEUTICS PLCSLN$36.4M3,311,4380.74%+0.31pp8q+13.7%+$4.4M
DENALI THERAPEUTICS INCDNLI$35.9M1,396,5130.73%-0.02pp8qHELD
REMITLY GLOBAL INCRELY$34.6M1,543,2710.70%+0.03pp8qHELD
CULLINAN THERAPEUTICS INCCGEM$34.5M1,893,4100.70%+0.23pp8q+58.7%+$12.7M
CAPITAL ONE FINL CORPCOF$34.4M171,6150.70%-newNEW
TREVI THERAPEUTICS INCTRVI$33.3M1,786,8670.67%+0.08pp7qHELD
ORIC PHARMACEUTICALS INCORIC$32.5M2,998,1920.66%-0.40pp8qHELD
ALPHABET INCGOOGL$32.2M90,0000.65%+0.13pp8q+37.0%+$8.7M
DBV TECHNOLOGIES S ADBVT$30.5M1,857,3620.62%-0.46pp3qHELD
ABSCI CORPORATIONABSI$28.7M2,474,7640.58%+0.43pp2q+37.5%+$7.8M
SIONNA THERAPEUTICS INCSION$26.9M610,5150.54%+0.21pp6q+103.5%+$13.7M
RAPPORT THERAPEUTICS INCRAPP$26.7M641,4690.54%-0.02pp8qHELD
AMYLYX PHARMACEUTICALS INCAMLX$26.6M1,480,5860.54%+0.06pp2q+20.4%+$4.5M
ANNEXON INCANNX$25.5M4,458,6460.52%-0.09pp2q+12.6%+$2.9M
MONOPAR THERAPEUTICS INCMNPR$25.0M270,1180.51%+0.10pp3qHELD
ORUKA THERAPEUTICS INCORKA$23.8M250,0000.48%-newNEW
SEAPORT THERAPEUTICS INCSPTX$23.8M1,095,3160.48%-newNEW
DAMORA THERAPEUTICS INCDMRA$23.4M900,0000.47%-0.17pp2qHELD
TYRA BIOSCIENCES INCTYRA$23.2M725,0000.47%-newNEW
MICROSOFT CORP OPTMSFT$22.9M37,5000.46%+0.04pp8q-9.4%-$2.4M
ZURA BIO LTDZURA$22.0M3,734,8660.45%-0.17pp3qHELD
TAIWAN SEMICONDUCTOR MANUFACTSM$21.3M44,7000.43%+0.04pp8q+5.9%+$1.2M
NVIDIA CORPORATIONNVDA$19.0M95,0000.38%-0.05pp8q+6.6%+$1.2M
REZOLUTE INCRZLT$17.3M3,328,2870.35%+0.07pp2qHELD
MAPLIGHT THERAPEUTICS INCMPLT$16.1M450,0000.33%+0.07pp3qHELD
NEUMORA THERAPEUTICS INC.NMRA$14.4M8,497,8220.29%-0.17pp8qHELD
NEBIUS GROUP N.V.NBIS$14.4M52,0000.29%-0.04pp7q-54.2%-$17.0M
CYTOMX THERAPEUTICS INCCTMX$13.0M3,457,7110.26%-0.19pp2qHELD
GENERATE BIOMEDICINES INCGENB$12.4M736,1040.25%flat2qHELD
INHIBIKASE THERAPEUTICS INCIKT$11.9M5,850,0000.24%-0.03pp3qHELD
ADAGENE INCADAG$11.2M2,666,6660.23%-newNEW
Engene Therapeutics IncENGN$10.8M6,256,6620.22%-newNEW
WHITEHAWK THERAPEUTICS INCWHWK$10.7M2,337,1020.22%+0.02pp6q+12.3%+$1.2M
DATADOG INCDDOG$10.4M40,0000.21%+0.03pp8q-26.3%-$3.7M
SERVICENOW INCNOW$9.9M100,0000.20%-0.05pp8q+14.8%+$1.3M
BROADCOM INCAVGO$9.4M25,0000.19%+0.06pp3q+66.7%+$3.8M
IONQ INCIONQ$9.1M170,0000.18%+0.05pp8qHELD
JFROG LTDFROG$8.7M95,5000.18%+0.01pp8q-25.9%-$3.0M
OCULIS HOLDING AGOCS$8.7M625,0000.18%-newNEW
IREN LIMITEDIREN$8.0M175,0000.16%+0.12pp4q+306.0%+$6.0M
AMAZON COM INCAMZN$7.7M32,5000.16%-0.11pp8q-30.3%-$3.4M
CROWDSTRIKE HLDGS INCCRWD$7.6M10,0000.15%-0.10pp8q-56.7%-$10.0M
DESIGN THERAPEUTICS INCDSGN$7.6M523,2120.15%-newNEW
PDD HOLDINGS INCPDD$7.2M95,0000.15%-0.09pp8q+13.9%+$884.8K
SATELLOS BIOSCIENCE INCMSLE$6.9M892,0740.14%flat2qHELD
DYNATRACE INCDT$6.8M155,0000.14%-0.02pp8q+3.3%+$219.5K
APPLE INC OPTAAPL$6.7Moptions only0.13%-newOPTIONS
TENAX THERAPEUTICS INCTENX$6.2M427,1410.13%-0.06pp4qHELD
VTV THERAPEUTICS INCVTVT$6.1M163,0000.12%-0.06pp4qHELD
ELOXX PHARMACEUTICALS INC$5.6M400,0000.11%-newNEW
AGOMAB THERAPEUTICS NVAGMB$5.3M411,2500.11%-0.01pp2qHELD
ALIBABA GROUP HLDG LTDBABA$4.8M50,0000.10%-newNEW
KORRO BIO INCKRRO$4.6M347,7180.09%-0.02pp8qHELD
CELLEBRITE DI LTDCLBT$4.5M311,5440.09%-0.03pp5qHELD
INVIVYD INCIVVD$4.4M5,000,0000.09%-0.06pp3q+25.0%+$872.4K
OUSTER INCOUST$4.2M67,5000.09%-newNEW
PALISADE BIO INCPALI$4.2M2,000,0000.08%-newNEW
AEVA TECHNOLOGIES INCAEVA$4.2M145,4590.08%+0.04pp2q+32.2%+$1.0M
SEER INCSEER$4.1M2,458,6730.08%-0.03pp8qHELD
NOVABRIDGE BIOSCIENCESNBP$3.9M2,004,7390.08%-0.13pp4q-33.2%-$1.9M
GITLAB INCGTLB$3.8M125,0000.08%+0.02pp5q+25.0%+$763.2K
ODYSSEY THERAPEUTICS INCODTX$3.7M200,0000.08%-newNEW
FOGHORN THERAPEUTICS INCFHTX$3.5M720,7200.07%-0.02pp8qHELD
AGENUS INCAGEN$3.3M1,064,2500.07%-0.03pp6qHELD
MONDAY COM LTDMNDY$3.1M42,5000.06%+0.01pp4q+70.0%+$1.3M
ZOETIS INCZTS$2.5M35,0000.05%-newNEW
WORKIVA INCWK$2.2M45,0000.04%-0.11pp7q-51.4%-$2.3M
NETFLIX INCNFLX$1.8M25,0000.04%-newNEW
KALARIS THERAPEUTICS INCKLRS$1.8M435,7980.04%-0.03pp6qHELD
QUANTINUUM INCQNT$1.6M20,0000.03%-newNEW
RANI THERAPEUTICS HLDGS INCRANI$1.5M2,000,0000.03%-0.01pp3qHELD
TESLA INCTSLA$1.5M3,5000.03%-0.19pp6q-83.7%-$7.6M
KE HLDGS INCBEKE$1.5M100,0000.03%-0.01pp8qHELD
ENTERA BIO LTDENTX$1.3M736,4570.03%-newNEW
MEDLINE INCMDLN$986.0K25,0000.02%-0.01pp3qHELD
LUMENTUM HLDGS INCLITE$905.3K1,0550.02%-newNEW
FIGMA INCFIG$904.5K50,0000.02%-0.01pp4qHELD
GOSSAMER BIO INCGOSS$857.4K5,208,9680.02%-0.03pp8qHELD
FOX CORPFOXA$521.6K10,0000.01%-newNEW
AT&T INCT$517.5K25,0000.01%-newNEW
NU HLDGS LTDNU$334.0K25,0000.01%flat2qHELD

By sector

Industry comes from the SIC code on each company's own SEC filings, which is self-reported and sometimes out of date. Derivative exposure is counted with the shares. Securities the SEC assigns no industry - funds, trusts, foreign issues - are shown as not classified rather than dropped.

Biotech & Pharma 88.1%Software & IT Services 3.6%Other sectors 3.4%Not classified 4.9%
 
SectorValueShare
Biotech & Pharma$4.4B88.1%
Software & IT Services$178.6M3.6%
Other sectors$169.6M3.4%
Not classified$242.0M4.9%

Quarter by quarter

QuarterValuePositions NewAddedTrimmed ExitedTop 10 Days to file
Q2 2026$4.9B1162631211044.6%44
Q1 2026$3.6B1001935183249.8%44
Q4 2025$3.4B1132630232846.3%44
Q3 2025$2.6B1152424141947.4%44
Q2 2025$1.9B1101521192148.5%44
Q1 2025$1.8B1162428382550.4%53
Q4 2024$2.3B1172222211548.5%45
Q3 2024$2.0B110000041.3%44

Rows marked UNVERIFIED ID, PLACEHOLDER ID, TICKER AS ID or NON-CUSIP ID carry an identifier that is not a valid CUSIP. They are shown because the filer reported that money, but treat the security named with caution - hover the chip for what is wrong with it, and see the methodology.

Held counts consecutive filings in which this manager reported the position, and can reach further back than the quarters listed above: the tabs begin at Q4 2018 because earlier coverage is too sparse to describe a market, but tenure is counted over every filing we hold, some reaching to 2007. A position sold and later rebought starts again from one.

Weight change is the shift in this position's share of the whole book, in percentage points. It is the more useful column: when money flows into or out of a broad fund, almost every holding is bought or sold at once, so added and trimmed largely track flows. A weight that rose while the book shrank is a decision. Both compare with the previous quarter this filer reported, not the previous calendar quarter.