Palo Alto Investors LP
Palo Alto Investors Palo Alto, CA 20 13Fs · since 2021 Q3
- AUM $654M
- positions 51
- period 2026 Q1
- QoQ −8.9%
- top 5 41.4%
- qoq N 5 E 3 A 15 R 14
- INSMED INC - INSM 10.4%
- ACADIA PHARMACEUTICALS INC - ACAD 9.8%
- PTC THERAPEUTICS INC - PTC 9.6%
- BIOMARIN PHARMACEUTICAL INC - BMRN 5.9%
- UNITED THERAPEUTICS CORP - UTHR 5.7%
- ANAPTYSBIO INC - ANAB 5.4%
- MIRUM PHARMACEUTICALS INC 4.6%
- DYNE THERAPEUTICS INC - DYN 4.6%
- BIOGEN INC - BIIB 3.9%
- DISC MEDICINE INC - IRON 3.9%
- IOVANCE BIOTHERAPEUTICS INC 3.4%
- SYNDAX PHARMACEUTICALS INC 3.1%
- Other 29.7%
AUM over time
Holdings value
2026 Q1
$654M
−8.9% QoQ
Latest book
| INSMED INC - INSM | 10.39% | Reduce −15.2% | 415,269 | $163.52 | $68M | −74,213 | −$17M |
| ACADIA PHARMACEUTICALS INC - ACAD | 9.78% | Add +15.6% | 2,872,695 | $22.26 | $64M | +388,664 | −$2M |
| PTC THERAPEUTICS INC - PTC | 9.60% | Add +2.0% | 921,607 | $68.13 | $63M | +17,691 | −$6M |
| BIOMARIN PHARMACEUTICAL INC - BMRN | 5.92% | Reduce −8.2% | 685,182 | $56.49 | $39M | −61,074 | −$6M |
| UNITED THERAPEUTICS CORP - UTHR | 5.70% | Add +7.9% | 62,809 | $592.98 | $37M | +4,623 | +$9M |
| ANAPTYSBIO INC - ANAB | 5.41% | Reduce −7.5% | 638,161 | $55.46 | $35M | −51,871 | +$2M |
| MIRUM PHARMACEUTICALS INC | 4.59% | Add +107.9% | 325,175 | $92.38 | $30M | +168,754 | +$18M |
| DYNE THERAPEUTICS INC - DYN | 4.58% | Add +12.3% | 1,652,972 | $18.13 | $30M | +180,775 | +$1M |
| BIOGEN INC - BIIB | 3.95% | Reduce −23.3% | 140,719 | $183.33 | $26M | −42,852 | −$7M |
| DISC MEDICINE INC - IRON | 3.93% | Add +26.5% | 401,719 | $63.94 | $26M | +84,263 | +$477 |
| IOVANCE BIOTHERAPEUTICS INC | 3.41% | Reduce −10.8% | 6,349,563 | $3.51 | $22M | −767,113 | +$3M |
| SYNDAX PHARMACEUTICALS INC | 3.09% | Add +8.9% | 864,986 | $23.36 | $20M | +70,479 | +$4M |
| ANNEXON INC - ANNX | 2.50% | Add +23.7% | 2,948,090 | $5.54 | $16M | +563,898 | +$4M |
| AMICUS THERAPEUTICS INC - AM6 | 2.46% | Reduce −78.6% | 1,113,045 | $14.46 | $16M | −4,092,722 | −$58M |
| NOVOCURE LTD | 2.13% | Reduce −1.4% | 1,280,439 | $10.90 | $14M | −18,525 | −$3M |
| ULTRAGENYX PHARMACEUTICAL IN | 1.91% | Add +29.3% | 596,495 | $20.95 | $12M | +135,201 | +$2M |
| PROTHENA CORP PLC | 1.80% | Reduce −8.5% | 1,208,568 | $9.72 | $12M | −111,942 | −$864 |
| BICARA THERAPEUTICS INC - BCAX | 1.67% | Add +84.3% | 550,408 | $19.89 | $11M | +251,833 | +$6M |
| CELLDEX THERAPEUTICS INC - CLDX | 1.44% | New | 296,408 | $31.72 | $9M | +296,408 | +$9M |
| CAREDX INC - CDNA | 1.41% | Add +11.2% | 531,870 | $17.36 | $9M | +53,650 | +$224 |
| ALKERMES PLC | 1.31% | 242,560 | $35.36 | $9M | — | — | |
| COMPASS THERAPEUTICS INC - CMPX | 1.23% | Reduce −40.2% | 1,514,504 | $5.29 | $8M | −1,017,915 | −$6M |
| AGIOS PHARMACEUTICALS INC - AGIO | 1.11% | Add +0.5% | 213,601 | $33.83 | $7M | +1,102 | +$1M |
| ALIGN TECHNOLOGY INC - ALGN | 1.09% | 41,520 | $171.43 | $7M | — | — | |
| CAPRICOR THERAPEUTICS INC - CAPR | 1.07% | Add +1.5% | 229,763 | $30.40 | $7M | +3,459 | +$454 |
| TRAVERE THERAPEUTICS INC | 1.05% | Add +108.1% | 230,453 | $29.71 | $7M | +119,734 | +$3M |
| TAYSHA GENE THERAPIES INC | 0.95% | Add +17.6% | 1,391,382 | $4.47 | $6M | +208,187 | −$288 |
| ACLARIS THERAPEUTICS INC - ACRS | 0.93% | Add +3.0% | 1,613,430 | $3.75 | $6M | +46,590 | +$1M |
| DENALI THERAPEUTICS INC - DNLI | 0.69% | Reduce −63.4% | 234,582 | $19.20 | $5M | −406,657 | −$6M |
| XENON PHARMACEUTICALS INC | 0.46% | Reduce −46.8% | 51,345 | $58.15 | $3M | −45,174 | −$1M |
| ORUKA THERAPEUTICS INC | 0.45% | 59,985 | $49.05 | $3M | — | — | |
| STOKE THERAPEUTICS INC | 0.42% | Add +17.5% | 84,631 | $32.56 | $3M | +12,609 | +$470 |
| EDWARDS LIFESCIENCES CORP - EW | 0.41% | 33,640 | $80.08 | $3M | — | — | |
| NEUROCRINE BIOSCIENCES INC - NBIX | 0.37% | 18,117 | $131.74 | $2M | — | — | |
| NUVATION BIO INC | 0.33% | Reduce −5.4% | 508,846 | $4.29 | $2M | −29,233 | −$3M |
| CYTOKINETICS INC - CYTK | 0.32% | New | 32,195 | $65.91 | $2M | +32,195 | +$2M |
| EHEALTH INC | 0.29% | Reduce −3.2% | 1,482,797 | $1.29 | $2M | −48,632 | −$5M |
| CRISPR THERAPEUTICS AG | 0.29% | Reduce −3.9% | 39,605 | $47.57 | $2M | −1,621 | −$278 |
| BIONTECH SE-ADR - BNTX | 0.27% | 19,614 | $88.88 | $2M | — | — | |
| PYXIS ONCOLOGY INC | 0.23% | Reduce −2.6% | 1,010,510 | $1.46 | $1M | −26,911 | +$282 |
| VERASTEM INC | 0.20% | New | 246,093 | $5.30 | $1M | +246,093 | +$1M |
| BICYCLE THERAPEUTICS PLC-ADR - BCYC | 0.14% | Reduce −8.7% | 201,890 | $4.64 | $937 | −19,181 | −$628 |
| MADRIGAL PHARMACEUTICALS INC | 0.14% | New | 1,787 | $523.47 | $935 | +1,787 | +$935 |
| HUMANA INC - HUM | 0.11% | 3,985 | $173.39 | $691 | — | — | |
| COMPASS PATHWAYS PLC ADR - CMPS | 0.10% | 115,616 | $5.53 | $639 | — | — | |
| XERIS BIOPHARMA HOLDINGS INC | 0.09% | New | 104,410 | $5.80 | $606 | +104,410 | +$606 |
| ABEONA THERAPEUTICS INC - ABEO | 0.07% | 108,865 | $4.48 | $488 | — | — | |
| INSPIRE MEDICAL SYSTEMS INC | 0.07% | 8,772 | $51.58 | $452 | — | — | |
| UROGEN PHARMA LTD | 0.07% | 24,500 | $17.98 | $441 | — | — | |
| PROQR THERAPEUTICS NV | 0.05% | 188,807 | $1.62 | $306 | — | — | |
| GOSSAMER BIO INC | — | Exit | 0 | $3.10 | — | −4,471,592 | −$14M |
| GENERATION BIO CO | — | Exit | 0 | $5.65 | — | −15,047 | −$85 |
| AKARI THERAPEUTICS PLC-ADR | — | Exit | 0 | $0.2876 | — | −146,024 | −$42 |
Showing top 50 of 51 by value · full holdings → · all activity →
* Reported price is value ÷ shares from the 13F as of period end — not a live market quote. Weight % is each long-equity position ÷ full 13F AUM, so rows may not sum to 100% when the filing includes options or other non-equity (excluded from this table). Share change and $ change are vs 2025 Q4. Click column headers to sort · click New / Exit / Add / Reduce to promote that move type to the top. Among managers we track.
filings history
20 periods · normalized AUM · click period for holdings
| Period | Holdings | AUM | QoQ | Form | Filed | Filing ID |
|---|---|---|---|---|---|---|
| 2026 Q1 | 51 | $654M | −8.9% | 13F-HR | 5/15/2026 | 000130692326000004 |
| 2025 Q4 | 49 | $718M | +33.0% | 13F-HR | 2/17/2026 | 000130692326000002 |
| 2025 Q3 | 44 | $540M | +14.9% | 13F-HR | 11/14/2025 | 000130692325000019 |
| 2025 Q2 | 45 | $470M | −10.5% | 13F-HR | 8/14/2025 | 000130692325000016 |
| 2025 Q1 | 44 | $525M | −18.6% | 13F-HR | 5/15/2025 | 000130692325000014 |
| 2024 Q4 | 43 | $645M | −16.2% | 13F-HR | 2/14/2025 | 000130692325000010 |
| 2024 Q3 | 45 | $770M | −10.8% | 13F-HR | 11/14/2024 | 000130692324000012 |
| 2024 Q2 | 39 | $863M | −2.7% | 13F-HR | 8/14/2024 | 000130692324000010 |
| 2024 Q1 | 38 | $887M | −19.9% | 13F-HR | 5/15/2024 | 000130692324000008 |
| 2023 Q4 | 34 | $1.1B | — | RESTATEMENT | 2/15/2024 | 000130692324000007 |
| 2023 Q4 | 34 | $1.1B | +4.7% | 13F-HR | 2/14/2024 | 000130692324000002 |
| 2023 Q3 | 29 | $1.1B | −14.6% | 13F-HR | 11/14/2023 | 000130692323000014 |
| 2023 Q2 | 30 | $1.2B | +2.6% | 13F-HR | 8/14/2023 | 000130692323000012 |
| 2023 Q1 | 30 | $1.2B | +2.9% | 13F-HR | 5/15/2023 | 000130692323000011 |
| 2022 Q4 | 29 | $1.2B | −7.3% | 13F-HR | 2/14/2023 | 000130692323000009 |
| 2022 Q3 | 32 | $1.3B | +10.3% | 13F-HR | 11/14/2022 | 000130692322000016 |
| 2022 Q2 | 33 | $1.1B | −11.3% | 13F-HR | 8/15/2022 | 000130692322000015 |
| 2022 Q1 | 35 | $1.3B | −17.4% | 13F-HR | 5/16/2022 | 000130692322000014 |
| 2021 Q4 | 37 | $1.6B | −5.6% | 13F-HR | 2/14/2022 | 000130692322000004 |
| 2021 Q3 | 42 | $1.7B | — | 13F-HR | 11/15/2021 | 000130692321000026 |
About
Palo Alto Investors LP
20 processed 13Fs · since 2021 Q3