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Palo Alto Investors 13F Holdings (Q2 2026)
According to its SEC 13F filed on Aug 19, 2026, Palo Alto Investors reported 52 long positions worth $724M as of Jun 30, 2026. PTCT is 10.4% of the portfolio and the top 10 holdings are 61%. Against Q1 2026 it opened 3 new positions, added to 5, trimmed 15 and exited 2. 14 holdings have a dated FDA decision or data readout in the next 90 days, and 19 more expect one in a stated window such as "H2 2026".
Catalysts ahead in this portfolio
Dated FDA decisions and data readouts for its holdings in the next 90 days, with our probability of approval
12 more with a subscription
What changed vs Q1 2026
Full lists with a subscription
Portfolio over time
13F value by quarter, Q1 2021 to Q2 2026
By company stage (share of value)
Holdings
Every position in the 13F, with the change since the fund's previous filing, how many of the 45 specialist funds also own it, and its next FDA catalyst. Option positions are labelled CALL or PUT.
| Stock | Company Name | Shares Held | Market Value | % of Portfolio | QoQ Change | Position Change | Also Held By | Stage | Next Catalyst |
|---|---|---|---|---|---|---|---|---|---|
 TRAX | FIRST TRACKS BIOTHERAPEUTICS | 603.49 K | 12.14 M | 1.7 | New | — | Nov 30, 2026 Phase 1b data presentation | ||
 CDNA | CAREDX INC | 531.87 K | 15.16 M | 2.1 | Unchanged | — | None in 90 days | ||
 IOVA | IOVANCE BIOTHERAPEUTICS INC | 5.30 M | 22.03 M | 3 | Trimmed -17% | Commercial | None in 90 days | ||
 ORKA | ORUKA THERAPEUTICS INC - Restricted | 33.55 K | 3.19 M | 0.4 | Trimmed -44% | Clinical | Expected 2026-12 Phase 2a data readout | ||
 URGN | UROGEN PHARMA LTD | 24.50 K | 901.60 K | 0.1 | Unchanged | Commercial | Expected 2H 2026 NDA Submission | ||
 SGMT | SAGIMET BIOSCIENCES INC-A | 250.00 K | 1.93 M | 0.3 | New | Clinical | Expected 2026 Phase 1 data readout |
Top 20 Holdings
Size = share of the portfolio. Option positions show CALL or PUT.
Who else owns these stocks?
All Stock Holdings ranks every biotech stock by how many of the 45 specialist funds own it, and whether that number rose or fell this quarter. Click "of 45 funds" on any row above, or open the full view.
Questions about Palo Alto Investors's 13F
What does Palo Alto Investors own?
52 stocks worth $724M at Jun 30, 2026, as reported in its 13F, led by PTCT (10.4% of the portfolio). The full list is in the Holdings table above.
What did it buy and sell last quarter?
Against Q1 2026: 3 new positions, 5 increases, 15 reductions and 2 full exits, from its 13F filings.
How current is this data?
13F filings are due 45 days after each quarter ends, so they show positions at quarter end, not today. The next filing (Q3 2026) is due Nov 16, 2026.
Why are some positions labelled CALL or PUT?
Those are option positions (calls and puts). The 13F reports them as the shares underlying the option, with no strike or expiry, so they are listed apart from share positions.
Source: SEC EDGAR Form 13F-HR filed by Palo Alto Investors LP, accession 0002073679-26-000102, filed Aug 19, 2026. Values as filed; option positions are shown at the value of the underlying shares and labelled CALL or PUT.