# Palo Alto Investors LP: Form 13F holdings

An institutional investment manager in PALO ALTO, CA. SEC CIK 1306923.

- Quarter ended: 2026-06-30
- Filed: 2026-08-19
- Reported value: $723.7m
- Positions: 52 (52 lines in the filing's table; lines for the same security and option type are added together here)
- Compared with: the 13F for the quarter ended 2026-03-31
- Filing: https://www.sec.gov/Archives/edgar/data/1306923/000207367926000102/

## Holdings

As filed, largest first. Reported value is what the manager stated at the quarter end (Jun 30, 2026), in US dollars; it is filing data, not a price. Weight is the share of the total reported value.

| Issuer | Class | Reported value | Weight | Shares | Put or call | Change on the quarter before |
| --- | --- | ---: | ---: | ---: | --- | --- |
| [PTC THERAPEUTICS INC (PTCT)](/companies/ptct.md) | COM | $75.0m | 10.4% | 918,846 |  | Reduced −2,761 |
| [ACADIA PHARMACEUTICALS INC (ACAD)](/companies/acad.md) | COM | $72.5m | 10.0% | 2,864,096 |  | Reduced −8,599 |
| [INSMED INC (INSM)](/companies/insm.md) | COM PAR $.01 | $44.1m | 6.1% | 413,980 |  | Reduced −1,289 |
| [MIRUM PHARMACEUTICALS INC (MIRM)](/companies/mirm.md) | COM | $40.8m | 5.6% | 348,808 |  | Added +23,633 |
| [ANAPTYSBIO INC (ANAB)](/companies/anab.md) | COM | $40.7m | 5.6% | 603,489 |  | Reduced −34,672 |
| [BIOMARIN PHARMACEUTICAL INC (BMRN)](/companies/bmrn.md) | COM | $39.1m | 5.4% | 682,777 |  | Reduced −2,405 |
| [DYNE THERAPEUTICS INC (DYN)](/companies/dyn.md) | COM | $36.6m | 5.1% | 1,647,521 |  | Reduced −5,451 |
| [UNITED THERAPEUTICS CORP (UTHR)](/companies/uthr.md) | COM | $33.9m | 4.7% | 62,587 |  | Reduced −222 |
| [DISC MEDICINE INC (IRON)](/companies/iron.md) | COM | $30.5m | 4.2% | 416,646 |  | Added +14,927 |
| [BIOGEN INC (BIIB)](/companies/biib.md) | COM | $30.3m | 4.2% | 140,279 |  | Reduced −440 |
| [IOVANCE BIOTHERAPEUTICS INC (IOVA)](/companies/iova.md) | COM | $22.0m | 3.0% | 5,296,209 |  | Reduced −1,053,354 |
| [ULTRAGENYX PHARMACEUTICAL IN (RARE)](/companies/rare.md) | COM | $19.9m | 2.8% | 596,495 |  | Unchanged |
| NOVOCURE LTD | ORD SHS | $19.4m | 2.7% | 1,280,439 |  | Unchanged |
| [SYNDAX PHARMACEUTICALS INC (SNDX)](/companies/sndx.md) | COM | $18.9m | 2.6% | 864,986 |  | Unchanged |
| [ANNEXON INC (ANNX)](/companies/annx.md) | COM | $16.8m | 2.3% | 2,948,090 |  | Unchanged |
| [BICARA THERAPEUTICS INC (BCAX)](/companies/bcax.md) | COM | $16.3m | 2.3% | 550,408 |  | Unchanged |
| [CAREDX INC (CDNA)](/companies/cdna.md) | COM | $15.2m | 2.1% | 531,870 |  | Unchanged |
| [CELLDEX THERAPEUTICS INC (CLDX)](/companies/cldx.md) | COM NEW | $14.9m | 2.1% | 399,856 |  | Added +103,448 |
| [COMPASS THERAPEUTICS INC (CMPX)](/companies/cmpx.md) | COM | $12.8m | 1.8% | 5,831,813 |  | Added +4,317,309 |
| ALKERMES PLC | SHS | $12.7m | 1.8% | 242,560 |  | Unchanged |
| [FIRST TRACKS BIOTHERAPEUTICS (TRAX)](/companies/trax.md) | ORD SHS | $12.1m | 1.7% | 603,489 |  | New +603,489 |
| PROTHENA CORP PLC | SHS | $11.2m | 1.5% | 1,143,155 |  | Reduced −65,413 |
| [TRAVERE THERAPEUTICS INC (TVTX)](/companies/tvtx.md) | COM | $9.5m | 1.3% | 167,525 |  | Reduced −62,928 |
| [TAYSHA GENE THERAPIES INC (TSHA)](/companies/tsha.md) | COM SHS | $9.5m | 1.3% | 1,391,382 |  | Unchanged |
| [ACLARIS THERAPEUTICS INC (ACRS)](/companies/acrs.md) | COM | $8.5m | 1.2% | 1,613,430 |  | Unchanged |
| [AGIOS PHARMACEUTICALS INC (AGIO)](/companies/agio.md) | COM | $7.9m | 1.1% | 213,601 |  | Unchanged |
| [CAPRICOR THERAPEUTICS INC (CAPR)](/companies/capr.md) | COM NEW | $5.5m | 0.8% | 229,763 |  | Unchanged |
| [ALIGN TECHNOLOGY INC (ALGN)](/companies/algn.md) | COM | $5.3m | 0.7% | 31,389 |  | Reduced −10,131 |
| [ORUKA THERAPEUTICS INC - Restricted (ORKA)](/companies/orka.md) | COM | $3.2m | 0.4% | 33,546 |  | Reduced −26,439 |
| [XENON PHARMACEUTICALS INC (XENE)](/companies/xene.md) | COM | $3.1m | 0.4% | 51,345 |  | Unchanged |
| [NEUROCRINE BIOSCIENCES INC (NBIX)](/companies/nbix.md) | COM | $3.1m | 0.4% | 18,117 |  | Unchanged |
| [EDWARDS LIFESCIENCES CORP (EW)](/companies/ew.md) | COM | $3.0m | 0.4% | 33,640 |  | Unchanged |
| [STOKE THERAPEUTICS INC (STOK)](/companies/stok.md) | COM | $2.8m | 0.4% | 84,631 |  | Unchanged |
| [CYTOKINETICS INC (CYTK)](/companies/cytk.md) | COM NEW | $2.7m | 0.4% | 32,195 |  | Unchanged |
| [PYXIS ONCOLOGY INC (PYXS)](/companies/pyxs.md) | COMMON STOCK | $2.6m | 0.4% | 864,277 |  | Reduced −146,233 |
| [EHEALTH INC (EHTH)](/companies/ehth.md) | COM | $2.2m | 0.3% | 1,482,797 |  | Unchanged |
| CRISPR THERAPEUTICS AG | NAMEN AKT | $2.2m | 0.3% | 39,605 |  | Unchanged |
| [SAGIMET BIOSCIENCES INC-A (SGMT)](/companies/sgmt.md) | COM SER A | $1.9m | 0.3% | 250,000 |  | New +250,000 |
| [NUVATION BIO INC (NUVB)](/companies/nuvb.md) | COM CL A | $1.9m | 0.3% | 326,609 |  | Reduced −182,237 |
| [BIONTECH SE-ADR (BNTX)](/companies/bntx.md) | SPONSORED ADS | $1.8m | 0.3% | 19,614 |  | Unchanged |
| [COMPASS PATHWAYS PLC ADR (CMPS)](/companies/cmps.md) | SPONSORED ADS | $1.6m | 0.2% | 115,616 |  | Unchanged |
| [HUMANA INC (HUM)](/companies/hum.md) | COM | $1.6m | 0.2% | 3,985 |  | Unchanged |
| NEWAMSTERDAM PHARMA CO NV | ORDINARY SHARES | $1.5m | 0.2% | 44,359 |  | New +44,359 |
| [VERASTEM INC (VSTM)](/companies/vstm.md) | COM NEW | $1.2m | 0.2% | 309,685 |  | Added +63,592 |
| [MADRIGAL PHARMACEUTICALS INC (MDGL)](/companies/mdgl.md) | COM | $959.5k | 0.1% | 1,787 |  | Unchanged |
| UROGEN PHARMA LTD | COM | $901.6k | 0.1% | 24,500 |  | Unchanged |
| [BICYCLE THERAPEUTICS PLC-ADR (BCYC)](/companies/bcyc.md) | SPONSORED ADS | $856.0k | 0.1% | 201,890 |  | Unchanged |
| [XERIS BIOPHARMA HOLDINGS INC (XERS)](/companies/xers.md) | COM | $826.9k | 0.1% | 104,410 |  | Unchanged |
| [ABEONA THERAPEUTICS INC (ABEO)](/companies/abeo.md) | COM NEW | $672.8k | <0.1% | 108,865 |  | Unchanged |
| [INSPIRE MEDICAL SYSTEMS INC (INSP)](/companies/insp.md) | COM | $391.3k | <0.1% | 8,772 |  | Unchanged |
| PROQR THERAPEUTICS NV | SHS EURO | $351.2k | <0.1% | 188,807 |  | Unchanged |
| [ALDEYRA THERAPEUTICS INC (ALDX)](/companies/aldx.md) | COM | $331.7k | <0.1% | 155,709 |  | Unchanged |

## Sold out

Held at the end of the quarter before and not reported this quarter.

| Issuer | Class | Reported value | Weight | Shares | Put or call | Change on the quarter before |
| --- | --- | ---: | ---: | ---: | --- | --- |
| AMICUS THERAPEUTICS INC | COM | $0 | 0.0% | 0 |  | Sold out −1,113,045 |
| [DENALI THERAPEUTICS INC (DNLI)](/companies/dnli.md) | COM | $0 | 0.0% | 0 |  | Sold out −234,582 |

Source: SEC EDGAR, Form 13F-HR, accession 0002073679-26-000102. Last ingested by Listed: Oct 22, 2026, 05:26 ET. No prices; not investment advice.