R.J. O'Brien & Associates

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R.J. O'Brien & Associates, LLC (a StoneX Group company)
Founded	1914
Headquarters	222 South Riverside Plaza, Suite 1200,Chicago, IL, 60606
Key People	Gerald F. Corcoran, Senior Managing Director, StoneX Group Inc.;
Employees	590
Twitter	@rjobrien
LinkedIn	Profile
Facebook	Page
Website	rjobrien.com

R.J. O'Brien & Associates, LLC (RJO) is a Chicago-based futures brokerage and clearing firm that operates as a subsidiary of StoneX Group Inc. following its acquisition by StoneX in 2025. Founded in 1914, RJO is the oldest independent futures commission merchant in the United States and was a founding member of the Chicago Mercantile Exchange (CME). The firm provides electronic trading execution, clearing services, and risk management to a global clientele that includes institutional, commercial, and individual investors.

As a part of StoneX Group Inc. (NASDAQ: SNEX), R.J. O'Brien contributes to the company’s global multi-asset execution, clearing, and risk management network. The acquisition positioned StoneX as the largest non-bank futures commission merchant (FCM) in the United States, expanding its reach across derivatives, foreign exchange, and fixed income markets. RJO continues to operate under its long-standing name within StoneX’s derivatives and clearing division.

History

R.J. O’Brien & Associates traces its history to 1914, when Irish immigrant John V. McCarthy founded John V. McCarthy & Co., a butter and egg trading firm in Chicago. The business joined the Chicago Butter and Egg Board that later evolved into the Chicago Mercantile Exchange, where it remains the only surviving original member firm. To support agricultural clients, McCarthy and his associates developed pioneering hedging strategies that aligned physical commodity trading with emerging futures markets.

The firm has been through four generations of family. In 1947, Robert O’Brien Sr. married Geraldine McCarthy, John’s daughter, and soon after joined the family business. John McCarthy died in 1963.

The firm took its modern name in 1969 after Robert J. O’Brien Sr. had joined the company in the 1940s and shifted its focus from spot trading to standardized futures. Under O’Brien’s leadership and that of his successors, the company gained prominence as a leading clearing member of several U.S. futures exchanges. As chairman of the CME in 1967, O’Brien Sr. played a critical role in developing contract specifications for livestock futures, helping institutionalize price discovery mechanisms in agricultural trading.

The firm has managed a variety of challenges over the years, including a drought, wars, market crashes, and even an outbreak of mad cow disease shortly before Christmas. RJO’s industry milestones have included taking delivery of the industry’s first futures contract based on a live animal and championing the rule change at CME to allow women on the trading floor (22-year-old Sandra Stephens, an RJO employee, became the first woman to work on the CME floor in 1966).

Leadership passed to Robert J. O’Brien Jr. and John W. O’Brien in the 1970s and 1980s, who oversaw the company’s adoption of electronic trading technology and global expansion into European markets, including operations at the London International Financial Futures Exchange (LIFFE). The firm diversified further under Gerald F. Corcoran, who became chief executive officer in 2000 and led modernization initiatives integrating advanced real-time risk management systems.

The Gerry Corcoran Years

Over the years, RJO diversified from being an introducing broker’s FCM into a full service firm offering a broad suite of services to retail and institutional customers. Much of its technology was built and developed in-house. RJO built its own electronic trading, brokerage and risk management technology and was one of the first firms to develop order routing. Even during a harsh environment in the industry, RJO grew dramatically into the largest independent futures brokerage, with 550 employees and more than 75,000 client accounts.

In 2007, the firm sold a majority stake to the investment firms Spectrum Equity Investors and Technology Crossover Ventures for an undisclosed sum, while the O’Brien family retained a minority ownership. In December 2010, RJO was back in the hands of the O’Brien family after the two private equity firms opted to sell back the control acquired in 2007. It remains majority-owned by the O’Brien family.

When MF Global declared bankruptcy in October 2011, RJO inherited a large number of its customers as regulators scrambled to move those customer accounts. RJO's segregated customer funds, which is the amount of customer funds held by the FCM, jumped almost $800 million to $3.3 billion, after MF Global fell, an increase of 31 percent.

RJO has been aggressive in building its business since, even as many firms were trimming down amid the crush of low to negative interest rates and increased regulatory burdens following the introduction of rules from the Dodd-Frank Act. In 2015, the company expanded its operations in the UK and Europe when it purchased London-based The Kyte Group, one of the largest clearing firms in Europe. It renamed the affiliate R.J. O'Brien Limited, which in 2024 had 100 employees and serves as the hub for the Europe, Middle East and Africa (EMEA region). RJO also continued to grow its Asian operations, and expanded in the FX space.

100th Anniversary

In 2014 at the Futures Industry Association's International Conference in Boca Raton, FL, RJO was honored an award for “100 years of excellence” in the futures industry.

The full-length version of the 100th anniversary video, which debuted October 17, 2014, can be seen on RJO's web site here. The video plus a brief write-up can be found on the JLN web site here.

StoneX Acquisition

RJO’s long-standing independence came to a close in 2025 after StoneX Group Inc. announced in April a definitive agreement to acquire the company in a $900 million cash-and-stock transaction. The deal, completed on July 31, 2025, created the largest non-bank futures commission merchant in the U.S. by client accounts and cleared volume, combining RJO’s 75,000 clients and 300 introducing brokers with StoneX’s global infrastructure and capital markets network.

Following the acquisition, R.J. O’Brien continues to operate from its Chicago headquarters as a StoneX subsidiary. Gerald F. Corcoran serves as senior managing director within StoneX Group, representing the company’s derivatives clearing and execution businesses.

Products and Services

RJO’s product portfolio encompasses futures and options execution, clearing services, and risk support for institutional investors, commercial hedgers, and introducing brokers. It retains its operational identity under the StoneX platform, providing clients with access to all major global exchanges, including the CME Group, Intercontinental Exchange (ICE), Euronext, and CBOE Global Markets.

Under StoneX, RJO’s clients now have expanded access to over-the-counter (OTC) hedging, liquidity services in fixed income markets, and cross-asset clearing across currencies, energy, and agricultural products. Its proprietary platforms—RJO WebOE and RJO MobileTrader—are being integrated into StoneX’s technology suite for electronic trading and risk management oversight. These systems also support VWAP execution and advanced order routing functionality.

RJO continues to maintain segregated client funds policies compliant with CFTC and NFA regulations. The firm does not engage in proprietary trading, a practice aligned with its long-standing conflict-avoidance and client-first operating principle.

The firm is an exchange member of:

• Bitnomial, Inc.
• Cboe Futures LLC
• Chicago Board of Trade
• Chicago Mercantile Exchange Inc.
• Commodity Exchange Inc.
• Dubai Mercantile Exchange Limited
• ICE Abu Dhabi (IFAD)
• ICE Endex (NDEX)
• ICE Futures US
• ICE Futures Europe
• New York Mercantile Exchange

The firm's Canadian affiliate, RJO Canada, is an exchange member of the Montreal Exchange.

The company's London-based affiliate, R.J. O'Brien Limited (RJO Limited) was approved as a Category 2 clearing member of the London Metal Exchange (LME) on July 23 and went live on August 19, 2015.

Key People

Executive Management

• Gerald F. Corcoran – Senior Managing Director, StoneX Group Inc. (former CEO, R.J. O'Brien)
• Heather Rucci – Chief Strategy Officer
• James Gabriele – Chief Financial Officer
• Brad Giemza – Chief Risk Officer
• Melissa Zierk – General Counsel
• John Robbins - Global Chief Compliance Officer

Risk Management

As part of StoneX Group Inc., R.J. O’Brien operates within a broad regulatory and operational risk framework that integrates credit risk, market risk, and compliance controls across asset classes. The company continues to oversee margin surveillance, client fund segregation, and prudent capital utilization standards under Commodity Futures Trading Commission (CFTC) supervision.

Through StoneX’s multi-asset platform, RJO benefits from enhanced liquidity management and global collateral optimization processes, fortified by daily stress testing and diversified portfolio hedging capabilities. The integration has also brought unified cross-margin systems for futures, options, and OTC derivatives.

Controversies

Prior to its acquisition, R.J. O’Brien faced regulatory matters concerning supervisory lapses. In 2013, the CFTC fined the firm $300,000 for failing to properly supervise a broker’s trade allocations. The agency cited violations of internal oversight procedures covering trading between 2003 and 2007. The firm subsequently overhauled its supervision frameworks.

In 2018, the CFTC issued a second order finding deficiencies in order allocation practices. R.J. O’Brien cooperated with regulators and enhanced its internal compliance systems in response. These incidents occurred amid a period of heightened regulatory scrutiny following collapses of MF Global and Refco, prompting industry-wide reforms in risk management for futures commission merchants.

Office Locations

North America
222 South Riverside Plaza, Suite 1200, Chicago, IL, 60606

1700-110 Yonge St., Toronto, ON. M5C 1T4, Canada

Europe
100 Cheapside, London, EC2V 6DT

Registration

• RJ OBRIEN ASSOCIATES LLC - NFA ID: 0000187