Fairmount Funds Management LLC — 13F Holdings & Portfolio

CIK 1802528 · latest 13F-HR filed 2026-08-14

Fairmount Funds Management LLC manages $1.51B in 13F-reported U.S. long-equity assets across 12 reported positions as of its 2026-06-30 13F-HR filing. Its largest disclosed positions are ORKA (23.31%), DNTH (16.35%), DMRA (14.98%). Quarter over quarter (versus its 2026-03-31 filing) the fund opened 1 new position, exited 1, added to 8, and trimmed 0.

AUM is the long-equity portion reported on Form 13F-HR. Excludes short positions, cash, foreign holdings, and non-13F assets. For informational purposes only — not investment advice.

Filer Information
Address
200 BARR HARBOR DRIVE
SUITE 400
WEST CONSHOHOCKEN, PA 19428
Phone
(267) 262-5300
Filing Manager
Fairmount Funds Management LLC
WEST CONSHOHOCKEN, PA
Signatory
Erin O'Connor
Chief Compliance Officer
Loading holdings…
AUM

$1.51B

Long-equity book

Holdings

12

Distinct positions

Period

2026-06-30

Filed 2026-08-14

Q/Q Activity

+1 / −1 / ↑8 / ↓0

vs 2026-03-31

Firm Profile & Key People
Name Title / Status Ownership Type

Top Adds (vs prior quarter)

  • ORUKA THERAPEUTICS INC$170.9M +94.0%
  • JADE BIOSCIENCES INC$37.2M +58.1%
  • DIANTHUS THERAPEUTICS INC$34.4M +16.2%
  • ENLIVEN THERAPEUTICS INC$21.4M +29.5%
  • VIRIDIAN THERAPEUTICS INC$17.0M +22.1%
Show all 8

Top Trims

  • No decreased positions.
Show all 0

New Positions

  • FAETH THERAPEUTICS INC$18.1M
Show all 1

Exited Positions

  • SPYRE THERAPEUTICS INC$202.7M
Show all 1
All Holdings

Rows tagged Call or Put are options positions, not stock. Per SEC Form 13F-HR, Value shows the notional value of the underlying (shares covered × underlying price), not the option premium. Shares is the number of underlying shares covered (divide by 100 for contract count).

# Issuer Symbol CUSIP Value Weight Shares Type
1 ORUKA THERAPEUTICS INC ORKA 687604108 $352.6M 23.31% 3,705,262 SH
2 DIANTHUS THERAPEUTICS INC DNTH 252828108 $247.3M 16.35% 2,537,191 SH
3 DAMORA THERAPEUTICS INC DMRA 36322Q206 $226.6M 14.98% 8,713,000 SH
4 COGENT BIOSCIENCES INC COGT 19240Q201 $213.0M 14.08% 5,503,418 SH
5 JADE BIOSCIENCES INC JBIO 008064206 $101.2M 6.69% 4,553,494 SH
6 ENLIVEN THERAPEUTICS INC ELVN 29337E102 $94.2M 6.22% 1,855,644 SH
7 VIRIDIAN THERAPEUTICS INC VRDN 92790C104 $93.5M 6.18% 5,090,928 SH
8 ZENAS BIOPHARMA INC ZBIO 98937L105 $59.9M 3.96% 2,359,025 SH
9 CRESCENT BIOPHARMA INC. CBIO G2545C104 $49.5M 3.27% 2,747,866 SH
10 APOGEE THERAPEUTICS INC APGE 03770N101 $39.6M 2.62% 298,647 SH
11 FAETH THERAPEUTICS INC FTH 81728A207 $18.1M 1.19% 722,020 SH
12 INHIBIKASE THERAPEUTICS INC IKT 45719W205 $17.5M 1.16% 8,625,000 SH
Filing History
Period Filed AUM Holdings Accession
2026-06-30 2026-08-14 $1.51B 12 0001104659-26-096405
2026-03-31 2026-05-15 $1.38B 12 0001104659-26-062419
2025-12-31 2026-02-17 $1.31B 13 0001104659-26-016303
2025-09-30 2025-11-14 $1.11B 17 0001104659-25-112427