BOOTHBAY FUND MANAGEMENT, LLC
Position in RARE — Ultragenyx Pharmaceutical Inc.
CIK 1549230
NEW YORK, NY
Position in RARE
as of Mar 31, 2026
· filed May 15, 2026
Position Value
$2,974,439
+$2,974,439 QoQ
Shares Held
141,978
Ownership
0.144%
of shares outstanding
% of Portfolio
0.07%
of 13F equity value
Holder Rank
—
not a current holder
Holding Since
Jun 2023
9 quarters on record
Voting authority
Sole 0.ToString("F0")%
Shared 100.ToString("F0")%
None 0.ToString("F0")%
Common Shares in RARE Over Time
Shares Held
Position Value (USD)
Derivatives in RARE
reported options exposure · as of Dec 31, 2025CallValue
$2,500,100
CallShares
108,700
PutValue
$1,552,500
PutShares
67,500
Notional value of option positions as reported on Form 13F. Calls and puts are disclosed separately and do not net against the common-share stake above.
Position in Biotechnology
Healthcare · as of Mar 31, 2026BOOTHBAY FUND MANAGEMENT, LLC holds $541,089,850 across 142 Biotechnology names. RARE ranks #42 (0.5% of the industry book) .
| # | Ticker | Company | Shares | Value (USD) | Open |
|---|---|---|---|---|---|
| 1 | ABVX |
Abivax S.A.
|
472,961 | $52,664,207 | |
| 2 | RVMD |
Revolution Medicines, Inc.
|
438,595 | $42,653,363 | |
| 3 | EXEL |
Exelixis, Inc.
|
803,866 | $34,477,812 | |
| 4 | PCVX |
Vaxcyte, Inc.
|
522,019 | $30,334,524 | |
| 5 | MLYS |
Mineralys Therapeutics, Inc.
|
1,001,728 | $27,136,811 | |
| 6 | TERN |
Terns Pharmaceuticals, Inc.
|
486,170 | $25,630,882 | |
| 7 | CGEM |
Cullinan Therapeutics, Inc.
|
1,112,803 | $15,812,930 | |
| 8 | XENE |
Xenon Pharmaceuticals Inc.
|
270,412 | $15,724,457 |
All Filings in RARE
Export CSV
15 filing rows on record
| Report Date | Value (USD) | Shares | Type | Discretion | Filed | |
|---|---|---|---|---|---|---|
| 2026-03-31 | $2,974,439 | 141,978 | Shares | Other | 2026-05-15 | |
| 2025-12-31 | $1,552,500 | 67,500 | Put | Other | 2026-02-17 | |
| 2025-12-31 | $2,500,100 | 108,700 | Call | Other | 2026-02-17 | |
| 2025-09-30 | $1,391,771 | 46,269 | Shares | Other | 2025-11-14 | |
| 2025-09-30 | $992,640 | 33,000 | Put | Other | 2025-11-14 | |
| 2025-06-30 | $3,926,880 | 108,000 | Put | Other | 2025-08-14 | |
| 2025-06-30 | $417,921 | 11,494 | Shares | Other | 2025-08-14 | |
| 2025-06-30 | $7,402,896 | 203,600 | Call | Other | 2025-08-14 | |
| 2025-03-31 | $2,377,367 | 65,655 | Shares | Other | 2025-05-15 | |
| 2025-03-31 | $1,097,163 | 30,300 | Put | Other | 2025-05-15 | |
| 2025-03-31 | $1,234,761 | 34,100 | Call | Other | 2025-05-15 | |
| 2024-12-31 | $2,290,921 | 54,455 | Shares | Other | 2025-02-14 | |
| 2024-09-30 | $3,025,586 | 54,466 | Shares | Other | 2024-11-14 | |
| 2023-09-30 | $1,340,119 | 37,591 | Shares | Other | 2023-11-14 | |
| 2023-06-30 | $1,143,747 | 24,794 | Shares | Other | 2023-08-14 | |
| No filing history on record for this holder in this stock. | ||||||