Key facts
- StoneX Financial is now the eighth-largest futures commission merchant (FCM) by futures and options (F&O) customer funds.
- The change occurred after trading and clearing services were transferred from RJ O’Brien Associates.
- The transfer of services was completed on May 31.
- StoneX acquired RJ O’Brien on July 31, 2025.
StoneX Financial has ascended to become the eighth-largest futures commission merchant (FCM) in terms of customer funds, following a significant transfer of futures and options (F&O) trading and clearing services from RJ O’Brien Associates. This strategic move, effective May 31, resulted in a substantial 61% increase in StoneX's customer funds. The acquisition of RJ O’Brien by StoneX was finalized on July 31, 2025, with the F&O activities previously managed by the Chicago-based broker now operating under the StoneX umbrella.