Palo Alto Investors LP is an institutional investment manager that files quarterly 13F reports with the SEC. As of Q4 2025, the fund manages $718M in reported equity holdings across 49 positions. The largest holdings are INSM (11.9%), FOLD (10.3%), PTCT (9.6%), ACAD (9.2%), BMRN (6.2%). The portfolio is concentrated in Other (100.0%). Data sourced from SEC EDGAR 13F filings (CIK 1306923).