Palo Alto Investors LP is an institutional investment manager that files quarterly 13F reports with the SEC. As of Q2 2026, the fund manages $724M in reported equity holdings across 52 positions. The largest holdings are PTCT (10.4%), ACHC (10.0%), INSM (6.1%), MIRM (5.6%), ANAB (5.6%). The portfolio is concentrated in Other (100.0%). Data sourced from SEC EDGAR 13F filings (CIK 1306923).