Gallin was born in 1940 in New York, the son of middle class Jewish parents. He started in the mailroom of General Artists Corporation, eventually becoming a senior vice president and board member. During this time he played a role in booking The Beatles on The Ed Sullivan Show.
In 1969 he left GAC to pursue personal management and production. Since then he has managed the careers of Cher, Dolly Parton, Michael Jackson, Neil Diamond, Barbra Streisand, Mariah Carey, and Whoopi Goldberg.
He's produced over 20 movies as well as Broadway plays, and has been the CEO of Mirage Entertainment and Sports. He is a close associate of Steve Wynn, Barry Diller, David Geffen, Diane Von Furstenberg, and Calvin Klein.
His 70th birthday party was thrown at Donna Karan's West Village studio, attended by Patti LaBelle, Barbra Streisand, Joan Rivers, Bette Midler, Vera Wang, Renée Zellweger, Richard Gere, Sandra Bernhard, Les Moonves, and Ron Perelman.
In 1988 Gallin battled cancer.
In 1997, Gallin was sued by two former employees alleging sexual harassment. The lawsuit alleged Gallin asked them to coordinate sexual visits with young men, as well as to offer their sexual services to potential clients to secure relationships.
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