Palo Alto Investors LP is an institutional investment manager that files quarterly 13F reports with the SEC. As of Q1 2026, the fund manages $654M in reported equity holdings across 51 positions. The largest holdings are INSM (10.4%), ACAD (9.8%), PTCT (9.6%), BMRN (5.9%), UTHR (5.7%). The portfolio is concentrated in Other (100.0%). Data sourced from SEC EDGAR 13F filings (CIK 1306923).