Marex Group plc (MRX) Institutional Ownership

Ownership Summary

A total of 190 institutions have reported a stake in Marex Group plc (NASDAQ:MRX) as of September 2025, according to recent 13F filings with the SEC.

• The percentage of Marex Group owned by institutions changed from 68.8% in June 2025 to 71.2% in September 2025, marking a slight up trend.
• Quarterly data indicates a 13.09% shift in institutional share volume, and the annual owner count reflects an increase of 171.43%.
• A review of institutional activity for Marex Group shows 122 of 190 filers increasing their positions, while 58 reduced their stake, and 10 remained unchanged.
• The total number of shares held by institutions in Marex Group increased to 51.43Mn as of September 2025, a net change of up by 5.95Mn shares quarter on quarter, and up 34.81Mn shares year over year.
• The top institutional stake in Marex Group as of September 30, 2025 belongs to BlackRock, Inc., which owns 3.72Mn shares, or 5.14% of the company.
• Among the most significant buyers of Marex Group during September 2025 were PRICE T ROWE ASSOCIATES INC /MD/ (1.20Mn), BlackRock, Inc. (1.19Mn), BALYASNY ASSET MANAGEMENT L.P. (677.70K), FMR LLC (602.28K), Man Group plc (559.70K).
• Leading sellers of Marex Group stock in September 2025 included Granahan Investment Management, LLC (1.02Mn), MILLENNIUM MANAGEMENT LLC (623.87K), MARSHALL WACE, LLP (603.73K), MORGAN STANLEY (485.14K), WILLIAM BLAIR INVESTMENT MANAGEMENT, LLC (442.34K).
• The top 10 institutional holders of Marex Group for the quarter ending September 2025 included BlackRock, Inc. (3.72Mn), Capital International Investors (3.49Mn), LOOMIS SAYLES & CO L P (1.79Mn), Grandeur Peak Global Advisors, LLC (1.75Mn), ALLIANCEBERNSTEIN L.P. (1.56Mn), JENNISON ASSOCIATES LLC (1.45Mn), ROYCE & ASSOCIATES LP (1.42Mn), ADAGE CAPITAL PARTNERS GP, L.L.C. (1.33Mn), Invesco Ltd. (1.21Mn), PRICE T ROWE ASSOCIATES INC /MD/ (1.21Mn).