Donald Drapkin, one of Ronald Perelman's closest associates until a bitter falling-out led to a lawsuit between the two men, died on Monday of injuries he suffered while skiing in Aspen, Co. Drapkin was 67.

Drapkin first worked for Perelman as a young partner at Skadden, Arps, Slate, Meagher & Flom, where Drapkin was an M&A lawyer. He represented Perelman and his investment vehicle MacAndrews & Forbes Holdings in 1985 on the hostile takeover of Revlon (REV) - Get Report , one of the signal deals of the 1980s. Drapkin left Skadden to work for Perelman in 1987 and stayed for the next two decades, in that time helping Perelman on numerous transactions. Drapkin served as a director at several of Perelman's companies, including Revlon.

In 2007, Drapkin left Perelman's employ to become a vice chairman at Lazard (LAZ) - Get Report . The close relationship between the two men had been degenerating for several years, and though friends and business associates tried to broker a truce, Drapkin sued Perelman in 2009 for $18 million in unpaid compensation that Drapkin claimed he was owed.

After a four-day trial in federal court in Manhattan in January 2012, a jury awarded Drapkin $16 million. He and Perelman soon settled the case on undisclosed terms. After leaving Lazard, Drapkin formed Casablanca Capital with former investment banker Douglas Taylor in 2010. Casablanca has been an activist investor in Mentor Graphics Corp. and Cliffs Natural Resources Inc.

"I was best friends with my partners at MacAndrews for 25 years," Drapkin told CNBC after the trial. "I mourn the loss of that friendship."

Drapkin was born on March 1, 1948, and grew up in Queens, N.Y. His father ran a cab company in Manhattan. He graduated from Brandeis University in 1968 and Columbia Law School three years later, then became an associate at Cravath, Swaine & Moore.

Drapkin moved to Skadden in 1977 and quickly became a protege of Joseph Flom, who built the firm into an M&A power. Drapkin kept the office next to Flom even after he made partner and became such a prominent takeover lawyer himself that New York magazine did a profile on him in 1986, the year before he went to work for Perelman. Drapkin remained very close to Flom and spoke at his memorial service in 2011.

Drapkin lived in Englewood, N.J., and had homes in Aspen and Miami. He is survived by his partner Sue Hostetler, with whom he lived in Aspen; his wife Bernice, from whom he had been separated; and five children, Amanda, Nicole, Matthew, David and Dana. Another son, Dustin, died in 2010.