Palo Alto Investors Lp
Institutional manager — quarterly 13F holdings, Q ending 2026-03-31
Reported value
$653.9M
Q ending 2026-03-31
Prior quarter
$718.4M
Q ending 2025-12-31
Change
-9.0% QoQ · +24.5% YoY
Positions
51
reported holdings
Largest positions
All 51 reported positions, Q ending 2026-03-31. A manager can hold shares, calls and puts on the same security at once — such positions are listed as separate rows. Type: Shares = common stock, Put/Call = option positions (valued at the underlying), Principal = debt. Tickers link to stock pages where covered.
| Holding | Ticker | Type | Value ▼ | Shares |
|---|---|---|---|---|
| Insmed Inc | INSM | Shares | $67.9M | 415K |
| Acadia Pharmaceuticals Inc | ACAD | Shares | $63.9M | 2.9M |
| Ptc Therapeutics Inc | PTCT | Shares | $62.8M | 922K |
| Biomarin Pharmaceutical Inc | BMRN | Shares | $38.7M | 685K |
| United Therapeutics Corp | UTHR | Shares | $37.2M | 63K |
| Anaptysbio Inc | ANAB | Shares | $35.4M | 638K |
| Mirum Pharmaceuticals Inc | MIRM | Shares | $30.0M | 325K |
| Dyne Therapeutics Inc | DYN | Shares | $30.0M | 1.7M |
| Biogen Inc | BIIB | Shares | $25.8M | 141K |
| Disc Medicine Inc | IRON | Shares | $25.7M | 402K |
| Iovance Biotherapeutics Inc | IOVA | Shares | $22.3M | 6.3M |
| Syndax Pharmaceuticals Inc | SNDX | Shares | $20.2M | 865K |
| Annexon Inc | ANNX | Shares | $16.3M | 2.9M |
| Amicus Therapeutics Inc | AM6 | Shares | $16.1M | 1.1M |
| Novocure Ltd | Shares | $14.0M | 1.3M | |
| Ultragenyx Pharmaceutical In | RARE | Shares | $12.5M | 596K |
| Prothena Corp Plc | Shares | $11.7M | 1.2M | |
| Bicara Therapeutics Inc | BCAX | Shares | $10.9M | 550K |
| Celldex Therapeutics Inc | CLDX | Shares | $9.4M | 296K |
| Caredx Inc | CDNA | Shares | $9.2M | 532K |
| Alkermes Plc | Shares | $8.6M | 243K | |
| Compass Therapeutics Inc | CMPX | Shares | $8.0M | 1.5M |
| Agios Pharmaceuticals Inc | AGIO | Shares | $7.2M | 214K |
| Align Technology Inc | ALGN | Shares | $7.1M | 42K |
| Capricor Therapeutics Inc | CAPR | Shares | $7.0M | 230K |
| Travere Therapeutics Inc | TVTX | Shares | $6.8M | 230K |
| Taysha Gene Therapies Inc | TSHA | Shares | $6.2M | 1.4M |
| Aclaris Therapeutics Inc | ACRS | Shares | $6.1M | 1.6M |
| Denali Therapeutics Inc | DNLI | Shares | $4.5M | 235K |
| Xenon Pharmaceuticals Inc | XENE | Shares | $3.0M | 51K |
| Oruka Therapeutics Inc | ORKA | Shares | $2.9M | 60K |
| Stoke Therapeutics Inc | STOK | Shares | $2.8M | 85K |
| Edwards Lifesciences Corp | EW | Shares | $2.7M | 34K |
| Neurocrine Biosciences Inc | NBIX | Shares | $2.4M | 18K |
| Nuvation Bio Inc | NUVB | Shares | $2.2M | 509K |
| Cytokinetics Inc | CYTK | Shares | $2.1M | 32K |
| Ehealth Inc | EHTH | Shares | $1.9M | 1.5M |
| Crispr Therapeutics Ag | Shares | $1.9M | 40K | |
| Biontech Se-Adr | BNTX | Shares | $1.7M | 20K |
| Pyxis Oncology Inc | PYXS | Shares | $1.5M | 1.0M |
| Verastem Inc | VSTM | Shares | $1.3M | 246K |
| Bicycle Therapeutics Plc-Adr | BCYC | Shares | $937K | 202K |
| Madrigal Pharmaceuticals Inc | MDGL | Shares | $935K | 2K |
| Humana Inc | HUM | Shares | $691K | 4K |
| Compass Pathways Plc Adr | CMPS | Shares | $639K | 116K |
| Xeris Biopharma Holdings Inc | XERS | Shares | $606K | 104K |
| Abeona Therapeutics Inc | ABEO | Shares | $488K | 109K |
| Inspire Medical Systems Inc | INSP | Shares | $452K | 9K |
| Urogen Pharma Ltd | Shares | $441K | 25K | |
| Proqr Therapeutics Nv | Shares | $306K | 189K | |
| Aldeyra Therapeutics Inc | ALDX | Shares | $263K | 156K |
Values as reported in public regulatory filings (USD); holdings are reported quarterly, up to 45 days after quarter end, and may contain reporting errors. Nothing here is investment advice.