One of the founders of Quinn Emanuel Urquhart & Sullivan's patent practice, Steven Anderson, has died after a yearslong struggle with lung cancer, the firm said. He was 55.

A statement posted Monday to Quinn Emanuel's website said Anderson had died on Dec. 27. A Los Angeles-based partner who represented clients such as DirecTV Inc., Anderson joined the firm in 1994 after graduating from Harvard Law School in 1989. He also held an undergraduate degree in information and computer science from the University of California, Irvine.

When he started at Quinn Emanuel, now a global litigation powerhouse, the firm had only about 30 lawyers, and Anderson was one of the founding members of its patent practice. That group has since become a leading national practice, with the firm handling a string of significant matters such as representing Samsung Electronics Co. Ltd. in the so-called smartphone patent wars with Apple Inc.

Anderson also played a role in the firm's mobile device litigation, representing Motorola Mobility in a now-settled patent dispute with Apple.

“Steve was smart, pragmatic, athletic, adventurous, and a fierce competitor. He loved boating, flying helicopters and being surrounded by family and friends,” Quinn Emanuel said on its website. “For the past 15 years he displayed indomitable courage and determination fighting illness, while continuing to contribute to the firm's success and enjoying life.”

The firm's statement noted that Anderson leaves behind a wife, Michelle, and a daughter, Sydney.

One of his colleagues, Los Angeles partner Michael Williams, said Monday that Anderson had a knack as a lawyer for distilling down complex, technical information. He knew how to fiercely litigate while maintaining a respectful and professional relationship with lawyers on the other side of a dispute, Williams said.

“He was one of these people who has the technical chops, but who can break it down and simplify it,” said Williams, who was a summer associate in 1994 when Anderson joined the firm and who worked alongside Anderson for the more than two decades since.

Williams also said Anderson was a talented athlete and was once the epitome of good health. About 15 years ago, when Anderson turned 40, his wife paid for him to have a full body medical scan, with an expectation that the results would show how fit Anderson was. Instead, said Williams, “They discovered a tumor on his lung. … It shocked everyone.”

The cancer diagnosis prompted a surgery, and for several years Anderson went into remission. During that period, Williams said his own mother was diagnosed with lung cancer, and Anderson, a “very caring, mentoring type of individual,” served as a resource for Williams and his family.

Later, Anderson's cancer returned and eventually spread. Williams said Anderson maintained a fighting spirit and an active law practice, even while battling the illness.

“He was the kind of guy where he wasn't going to let this thing interfere with his life,” Williams said. “No matter how painful it was, he wanted to continue an active life, traveling with his daughter and wife and coming in to practice law.”