GROUP ONE TRADING LLC is an institutional investment manager that files quarterly 13F reports with the SEC. As of Q2 2026, the fund manages $71.1B in reported equity holdings across 7824 positions. The largest holdings are MU (3.4%), MU (2.8%), GLD (1.9%), SNDK (1.8%), TSLA (1.7%). The portfolio is concentrated in Other (86.2%), Technology (5.4%), Communication Services (2.3%). Data sourced from SEC EDGAR 13F filings (CIK 932540).