Industry veteran Leonard S. Gruenberg died of natural causes Jan. 28 at home in Rancho Mirage, Calif. He was 83.

He began a 60-year career as a salesman for RKO in Minneapolis and was soon made a metropolitan division manager in New York.

He founded Gamma III, which released such films as “Dear John” and “Closely Watched Trains,” as well as two of Robert De Niro’s earliest films, “Greetings” (1968) and “Hi Mom” (1970). When Gamma III merged with Filmways, Gruenberg was chairman of the board.

On Broadway, he produced “Compulsion” (1957) and started his own production company, Sigma III, which made “Sounder II,” “Birch Interval” and Roger Vadim’s “Lady With Red Boots.”

He also served as president of Great Owl Prods, and during his tenure put together financing for Cinema Group and Paramount’s “Flashdance” and “Star Trek III: The Search for Spock.”

He served in the Navy in World War II.

He is survived by his wife, Babette; his brother, Jerry; son, Bud; daughter, Anne Brodie; eight grandchildren; one greatgrandchild; and four nephews, including Andy Gruenberg, executive VP of distribution for MGM/UA, producer Tom Gruenberg and John Gruenberg, Eastern division manager for Savoy Pictures.

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