JANA Partners Management, LP is an institutional investment manager that files quarterly 13F reports with the SEC. As of Q1 2026, the fund manages $1.6B in reported equity holdings across 10 positions. The largest holdings are MRCY (18.6%), COO (15.9%), FISV (15.4%), SPY (13.9%), LW (13.2%). The portfolio is concentrated in Other (84.1%), Healthcare (15.9%). Data sourced from SEC EDGAR 13F filings (CIK 1998597).