In addition to managing his family office, Grand Teton Group, Inc., Mark Mitchell is Founding Principal at AQR Arbitrage, LLC, an investment management firm specializing in arbitrage and based in Greenwich, CT. AQR Arbitrage has become one of the largest and premier arbitrage firms with institutional clients around the world. Mark is also Adjunct Professor of Finance at the University of Chicago since 2017.

Prior to co-founding AQR Arbitrage, LLC in 2001 (then known as CNH Partners), Mark was a finance professor at the University of Chicago (1990-1999) and Harvard University (1999-2003) where he authored numerous research papers about mergers & acquisitions and investment management.  During Mark’s tenure in academia at Chicago and Harvard, he won four paper-of-the-year awards and five teaching awards. To this day, Mark Mitchell continues to be actively involved in writing academic papers.

During 1996-2020, Mark served on the board of directors at TD-Ameritrade Holding Corporation for the entire public history of the firm and was the only board member to do so. Mark served on numerous committees during his tenure: Audit Committee, HR & Compensation Committee, M&A Committee (Chair), Outside Independent Director’s Committee, Risk Committee (Chair), Special Committee (Chair), and Strategic Development Committee.

In other board experience, Mark served on the board of CNH Finance, a specialty-finance firm during its entire history (2012-2022) until it was acquired by eCapital Corporation. Other board and committee experience included Gainskeeper, Inc. (Board Member, 2000-2002, until acquired by Wolters Kluwer), Frontier Airlines Unsecured Creditor Committee (2008-2009), NASD Economic Advisory Board (1996-1998), and NASDAQ Quality of Markets Committee (2003-2005). In February 2007, Mark served as an emissary of the U.S. State Department to discuss M&A with policymakers, business leaders, and reporters in Japan.

After obtaining a M.A. and Ph.D. in Economics at Clemson University, Mark began his career at the Securities & Exchange Commission in The Office of the Chief Economist during 1987-1990. At the SEC, Mark authored several research papers, worked on merger regulations, and led the development of applying financial economics to assist the SEC’s enforcement efforts in insider trading cases. According to the editors of The Wall Street Journal, Mark’s research at the SEC was “not only excellent, but also pertinent economic history.

Cyndi Cooksey joined Grand Teton Group, Inc. as Managing Director in 2015, heading up administration, finance, and legal. Additionally, she worked as an Adjunct Instructor of Economics from 2009 – 2015, teaching both undergraduate and graduate level courses.

Cyndi received a B.S. in Economics from Clemson University in 1985, graduating Magna Cum Laude. She was awarded the Liberty Life Fellowship for graduate school and chose to remain at Clemson where she received her M.A. in Economics in 1986. She was honored to be the recipient of the Hugh H. Macaulay Award for the Outstanding Graduate Student in Economics.

From 2010 – 2020, she served on the Senior Advisory Board for the Clemson University College of Business. She also served as a mentor and business coach for students in the MBA in Entrepreneurship Program at Clemson. Currently, she serves on various Alumni Panels for undergraduates in the College of Business.

Greg Pepe joined Grand Teton Group, Inc. as Managing Director in 2026. Greg oversees the growth and strategic direction of the firm’s investment portfolio, working closely with leadership teams at companies where the firm holds full or significant ownership positions. He takes a hands-on, relationship-driven approach, partnering with executives to provide added perspective and support where it’s most helpful.

Greg began his career at IBM Credit Corporation before joining American Airlines in marketing and advertising sales. He later became a partner in an advertising sales and marketing agency that was acquired by a large multinational paper, packaging, and marketing services company. This mix of corporate, entrepreneurial, and operating experience shapes his practical, execution-focused approach to working with portfolio companies.

Known for his energy and interest in people and businesses, Greg enjoys engaging directly with leadership teams to understand their goals and help companies perform at the highest level in their markets. Greg earned a BA in Economics from the University at Albany, and an MBA in Marketing from Pace University.