CITADEL ADVISORS LLC is an institutional investment manager that files quarterly 13F reports with the SEC. As of Q4 2025, the fund manages $665.9B in reported equity holdings across 6510 positions. The largest holdings are SPY (5.9%), IWM (5.4%), TSLA (5.2%), NVDA (4.3%), AAPL (2.5%). The portfolio is concentrated in Other (85.5%), Communication Services (5.0%), Technology (2.9%). Data sourced from SEC EDGAR 13F filings (CIK 1423053).