Skip to content
Disclosery

Fairmount Funds Management LLC

Follow

13F filer, CIK 1802528, WEST CONSHOHOCKEN, PA

Fairmount Funds Management LLC reported $1,384,339,432 across 12 holdings for the quarter ended 2026-03-31, in a 13F-HR filed 2026-05-15. Its ten largest share positions make up 97.14% of the portfolio.

Filed (acceptance time not in the bulk data set), ingested 13F-HR 0001104659-26-062419

Period
2026-03-31
Reported value
$1.38B
Holdings
12
Top 10 weight
97.14%
New
1
Sold out
2

Part of the filer group Fairmount Funds Management LLC

  • Fairmount Healthcare Fund II L.P.
  • Harwin Peter Evan
  • Kiselak Tomas
How groups are built

Largest buys vs the previous quarter

SecurityShares changeApprox. value
DMRAnew+8,713,000$226M
DNTHadded+400,000$33.6M
ZBIOadded+150,000$2.93M

Ranked by the share change valued at this quarter's implied price (value over shares in the 13F). A position sold out is valued at the previous quarter's price, its last report.

Largest sells vs the previous quarter

SecurityShares changeApprox. value
APGEreduced-1,750,000-$147M
COGTreduced-3,500,000-$135M
NUVLexited-727,563-$73.2M
ELVNreduced-1,855,800-$72.7M
KNSAexited-1,319,688-$54.4M

Ranked by the share change valued at this quarter's implied price (value over shares in the 13F). A position sold out is valued at the previous quarter's price, its last report.

Holdings, Q1 2026

Share positions as resolved from 13F-HR 0001104659-26-062419, largest first. % of portfolio is the value over $1,384,339,432, the sum of the share positions whose value is usable for ratios (method).

SecurityHistorySharesValue% of portfolioChangeLatest eventTimeline
DMRADAMORA THERAPEUTICS INCQuarterly shares; oldest to newest; scale is this security's eight-quarter maximum; 2024Q2: restricted; 2024Q3: not reported; 2024Q4: not reported; 2025Q1: not reported; 2025Q2: not reported; 2025Q3: not reported; 2025Q4: not reported; 2026Q1: 8,713,000 shares 8,713,000$226M16.3%newTimeline
DNTHDIANTHUS THERAPEUTICS INCQuarterly shares; oldest to newest; scale is this security's eight-quarter maximum; 2024Q2: restricted; 2024Q3: 2,700,691 shares; 2024Q4: 2,700,691 shares; 2025Q1: 2,700,691 shares; 2025Q2: 2,707,191 shares; 2025Q3: 3,307,191 shares; 2025Q4: 2,137,191 shares; 2026Q1: 2,537,191 shares 2,537,191$213M15.38%+400,000Timeline
COGTCOGENT BIOSCIENCES INCQuarterly shares; oldest to newest; scale is this security's eight-quarter maximum; 2024Q2: restricted; 2024Q3: 6,225,641 shares; 2024Q4: 6,225,641 shares; 2025Q1: 6,225,641 shares; 2025Q2: 6,225,641 shares; 2025Q3: 9,003,418 shares; 2025Q4: 9,003,418 shares; 2026Q1: 5,503,418 shares 5,503,418$212M15.3%-3,500,000Timeline
SYRESPYRE THERAPEUTICS INCQuarterly shares; oldest to newest; scale is this security's eight-quarter maximum; 2024Q2: restricted; 2024Q3: 4,018,101 shares; 2024Q4: 4,018,101 shares; 2025Q1: 4,018,101 shares; 2025Q2: 4,018,101 shares; 2025Q3: 4,018,101 shares; 2025Q4: 4,018,101 shares; 2026Q1: 4,018,101 shares 4,018,101$203M14.64%02026-10-07, 13D/A: 10,185,961 shares, 9.99% of the class, 13D/A filed 2026-10-09 Timeline
ORKAORUKA THERAPEUTICS INCQuarterly shares; oldest to newest; scale is this security's eight-quarter maximum; 2024Q2: restricted; 2024Q3: 3,211,922 shares; 2024Q4: 3,371,922 shares; 2025Q1: 3,371,922 shares; 2025Q2: 3,371,922 shares; 2025Q3: 3,705,262 shares; 2025Q4: 3,705,262 shares; 2026Q1: 3,705,262 shares 3,705,262$182M13.13%0Timeline
VRDNVIRIDIAN THERAPEUTICS INCQuarterly shares; oldest to newest; scale is this security's eight-quarter maximum; 2024Q2: restricted; 2024Q3: 3,445,813 shares; 2024Q4: 3,445,813 shares; 2025Q1: 3,445,813 shares; 2025Q2: 3,459,913 shares; 2025Q3: 3,459,913 shares; 2025Q4: 3,914,458 shares; 2026Q1: 3,914,458 shares 3,914,458$76.6M5.53%0Timeline
ELVNENLIVEN THERAPEUTICS INCQuarterly shares; oldest to newest; scale is this security's eight-quarter maximum; 2024Q2: restricted; 2024Q3: 3,202,798 shares; 2024Q4: 3,202,798 shares; 2025Q1: 3,202,798 shares; 2025Q2: 3,711,444 shares; 2025Q3: 3,711,444 shares; 2025Q4: 3,711,444 shares; 2026Q1: 1,855,644 shares 1,855,644$72.7M5.25%-1,855,800Timeline
JBIOJADE BIOSCIENCES INCQuarterly shares; oldest to newest; scale is this security's eight-quarter maximum; 2024Q2: restricted; 2024Q3: not reported; 2024Q4: not reported; 2025Q1: not reported; 2025Q2: 3,220,368 shares; 2025Q3: 3,220,368 shares; 2025Q4: 4,553,494 shares; 2026Q1: 4,553,494 shares 4,553,494$64M4.62%0Timeline
CBIOCRESCENT BIOPHARMA INC.Quarterly shares; oldest to newest; scale is this security's eight-quarter maximum; 2024Q2: restricted; 2024Q3: not reported; 2024Q4: not reported; 2025Q1: not reported; 2025Q2: 1,387,866 shares; 2025Q3: 1,387,866 shares; 2025Q4: 2,747,866 shares; 2026Q1: 2,747,866 shares 2,747,866$50.5M3.65%0Timeline
ZBIOZENAS BIOPHARMA INCQuarterly shares; oldest to newest; scale is this security's eight-quarter maximum; 2024Q2: restricted; 2024Q3: 1,892,806 shares; 2024Q4: 1,892,806 shares; 2025Q1: 1,892,806 shares; 2025Q2: 1,892,806 shares; 2025Q3: 1,892,806 shares; 2025Q4: 2,209,025 shares; 2026Q1: 2,359,025 shares 2,359,025$46.1M3.33%+150,000Timeline
APGEAPOGEE THERAPEUTICS INCQuarterly shares; oldest to newest; scale is this security's eight-quarter maximum; 2024Q2: restricted; 2024Q3: 2,048,647 shares; 2024Q4: 2,048,647 shares; 2025Q1: 2,048,647 shares; 2025Q2: 2,048,647 shares; 2025Q3: 2,048,647 shares; 2025Q4: 2,048,647 shares; 2026Q1: 298,647 shares 298,647$25.1M1.82%-1,750,000Timeline
IKTINHIBIKASE THERAPEUTICS INCQuarterly shares; oldest to newest; scale is this security's eight-quarter maximum; 2024Q2: restricted; 2024Q3: not reported; 2024Q4: 6,125,000 shares; 2025Q1: 6,125,000 shares; 2025Q2: 6,125,000 shares; 2025Q3: 6,125,000 shares; 2025Q4: 8,625,000 shares; 2026Q1: 8,625,000 shares 8,625,000$14.5M1.05%0Timeline

Sold out in Q1 2026

Positions in the previous quarter's report that this quarter's report no longer lists.

SecurityShares beforeValue beforeType
NUVLNUVALENT INC727,563$73.2Mshares
KNSAKINIKSA PHARMACEUTICALS INTL1,319,688$54.4Mshares

How Q1 2026 was built

Available 13F filings of this filer for the quarter and their roles: the base report is the latest original or restatement, NEW HOLDINGS amendments filed after it are added (method).

FilingRoleAmendmentFiledAcceptedIngested
13F-HR 0001104659-26-062419 base2026-05-15acceptance time not in the bulk data set