Rambus Inc (RMBS) Institutional Ownership

Ownership Summary

According to SEC filings for the period ending September 2025, Rambus Inc (NASDAQ:RMBS) is held by 505 institutional firms.

• Institutional ownership in Rambus edged up to 92.6% in September 2025, compared to 90.5% in June 2025.
• Quarterly data indicates a 1.75% shift in institutional share volume, and the annual owner count reflects an increase of 35.03%.
• A review of institutional activity for Rambus shows 255 of 505 filers increasing their positions, while 196 reduced their stake, and 54 remained unchanged.
• Collectively, institutional investors increased their stake in Rambus to 99.65Mn shares as of September 2025, a change that is up by 1.71Mn shares quarter on quarter and up 7.06Mn shares year over year.
• BlackRock, Inc.'s holding of 15.81Mn shares as of September 30, 2025 makes it the primary institutional investor in Rambus, owning 14.69% of the stock.
• Among the most significant buyers of Rambus during September 2025 were ALLIANCEBERNSTEIN L.P. (1.55Mn), FMR LLC (1.04Mn), BANK OF AMERICA CORP /DE/ (1.03Mn), BlackRock, Inc. (808.61K), BARCLAYS PLC (578.84K).
• Leading sellers of Rambus stock in September 2025 included OAK RIDGE INVESTMENTS LLC (1.79Mn), WESTWOOD HOLDINGS GROUP INC (1.50Mn), Assenagon Asset Management S.A. (786.91K), JPMORGAN CHASE & CO (623.54K), WESTFIELD CAPITAL MANAGEMENT CO LP (477.95K).
• The top 10 institutional holders of Rambus for the quarter ending September 2025 included BlackRock, Inc. (15.81Mn), VANGUARD GROUP INC (12.70Mn), PRICE T ROWE ASSOCIATES INC /MD/ (5.25Mn), STATE STREET CORP (4.39Mn), GEODE CAPITAL MANAGEMENT, LLC (2.75Mn), EdgePoint Investment Group Inc. (2.68Mn), JPMORGAN CHASE & CO (2.56Mn), Invesco Ltd. (2.43Mn), DIMENSIONAL FUND ADVISORS LP (1.93Mn), ALLIANCEBERNSTEIN L.P. (1.82Mn).