System1, Inc. (SST) Institutional Ownership

Ownership Summary

System1, Inc. (NYSE:SST) has 23 institutional investors that have filed 13F reports for the period ending December 2025.

• Their combined ownership stood at 10.1% of outstanding shares in December 2025, down from 41.6% in September 2025.
• They decreased total shares held in System1 by -75.36% from the prior quarter, while the number of investors in SST decreased 61.67% year over year.
• Of these 23 holders, 5 added to their stakes in System1, 13 trimmed positions, and 5 made no changes.
• Combined, these investors held 815.64K shares in SST for December 2025, down by 2.5Mn shares quarter on quarter, and down 34.7Mn shares year over year.
• Cannae Holdings, Inc. is the top holder of System1 as of December 31, 2025, with 356.8K shares representing 4.43% of outstanding stock.
• The most significant purchases of SST for the quarter ending December 2025 came from VANGUARD CAPITAL MANAGEMENT LLC (37.13K), NINE MASTS CAPITAL Ltd (18.55K), GEODE CAPITAL MANAGEMENT, LLC (9.48K), VANGUARD FIDUCIARY TRUST CO (9.14K), Tower Research Capital LLC (TRC) (6.34K).
• The biggest sellers of System1 for the quarter ending December 2025 included MILLENNIUM MANAGEMENT LLC (2.83K), GROUP ONE TRADING LLC (440), RENAISSANCE TECHNOLOGIES LLC (300), Royal Bank Of Canada (69), Bank Of America Corp /De/ (27).
• Per Business Quant data, the top 10 holders of System1 for the quarter ending December 2025 are Cannae Holdings, Inc. (356.8K), Bank Of America Corp /De/ (161.52K), Cerity Partners LLC (116.84K), VANGUARD CAPITAL MANAGEMENT LLC (37.13K), MILLENNIUM MANAGEMENT LLC (32.62K), BlackRock, Inc. (24.25K), GEODE CAPITAL MANAGEMENT, LLC (23.84K), NINE MASTS CAPITAL Ltd (18.55K), RENAISSANCE TECHNOLOGIES LLC (18.32K), State Street Corp (11.5K).