Boies Schiller Flexner (BSF) is mourning the loss of founding partner and antitrust titan Donald Flexner, who passed away last Sunday aged 81.

Flexner died after a long illness in the presence of family, the firm said. One of the most successful antitrust lawyers in America, Flexner’s decades-long career spanned leadership positions at the Department of Justice and Crowell & Moring before founding BSF in 1999 alongside David Boies and Jonathan Schiller. 

“Don was a great lawyer, a giant of the Antitrust Bar. He was also a great friend and partner, a leader and builder on whom we all could, and did, rely,” Boies said in a statement on Sunday. 

Flexner joined the antitrust division of the Department of Justice after graduating from NYU Law School and eventually rose to become section chief and acting assistant attorney general. 

From there he joined Crowell & Moring, where he spent 19 years in charge of the firm’s antitrust group and served as its presiding partner. His time at the firm included overseeing the landmark US. v. AT&T antitrust litigation that led to the breakup of the telecoms monopoly known as the Bell System in 1983. 

At BSF Flexner played a central role in growing the firm from a small boutique into an Am Law 200 litigation powerhouse. He stepped down from the co-managing partner role in 2017 but remained at the firm as a partner. 

Joanna Wright, BSF partner and member of the firm’s executive committee, said: “I was lucky to be mentored by Don; working on cases with him remains a highlight of my career. He was the type of person who, when he called to check in, really checked in with you, looking past pleasantries to how you were actually doing.  

“He leaves the profession with generations of lawyers mentored by him who will carry forward his formidable advocacy but also his unfailing civility. We are all better for having known him.”

During his more than 20 years at BSF, Flexner worked for clients including Chevron Corporation, DuPont de Nemours & Co and Honeywell, and acted as a lead lawyer in American Express’ landmark antitrust case against Visa and Mastercard, recovering more than $4bn – the largest antitrust recovery to date for a single plaintiff. 

He also helped to create what was then the world’s largest airline through his work on Delta’s acquisition of Northwest Airlines in 2008. 

Eric Brenner, New York administrative partner and BSF general counsel, commented: “Don was a force of nature. He would call first thing every morning to ensure the case team was organised. And no lawyer worked harder, thought more deeply, or cared more passionately about his clients--all while being an exemplary gentleman. He was an incredible role model and mentor to me and so many other BSF lawyers.”

Boies added: “He was the only highly successful lawyer I know whom everyone liked. He was both a rock for his firm, friends and family, and a hard place for those that wished them ill. But he always fought with integrity, and with respect for the rules. Even his opponents respected him, and with few exceptions, like Donald Trump and Alan Dershowitz, he always respected those he opposed. He leaves this firm, the justice system and the world better than he found them. We are all grateful.”

BSF's fellow co-founders, Boies (chairman) and Schiller (managing partner), remain at the helm of the firm.

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