He was soon promoted to agent, with a salary of $38 a week, before eventually moving to the company’s Los Angeles office, where he specialized in packaging mid-1960s TV series like “Gomer Pyle — USMC” and “That Girl” with the actors, writer and directors represented by William Morris.
But Mr. Shapiro disliked being responsible for so many clients, and so in 1973 he started his own management firm to focus on a few preferred ones. Mr. West, with whom he had worked at William Morris, soon joined him, and they ran Shapiro/West & Associates until Mr. West’s death in 2015.
To push for a sitcom for Mr. Seinfeld, Mr. Shapiro sent numerous letters to Brandon Tartikoff, the president of NBC Entertainment. The nudging eventually led to a meeting with Mr. Tartikoff and other network executives at which Mr. Seinfeld laid down a firm rule.
“Jerry made one thing clear,” Mr. Shapiro told the Television Academy. “He said, ‘I’m not going to play a shoe salesman or an accountant or a father with a job.’ And he came up with the premise of the series, that he would play himself.”
In recent years, Mr. Shapiro produced “If You’re Not in the Obit, Eat Breakfast” (2017), a documentary in which Mr. Reiner talked to nonagenarians like Betty White and Dick Van Dyke, and “The Super Bob Einstein Movie” (2021), about the comic actor and writer known for his ongoing television portrayal of Super Dave Osborne, a hapless parody of a daredevil.
Mr. Shapiro is survived by his former wife, Melody (Sherr) Shapiro, from whom he was divorced; his daughters, Carrie Shapiro Fuentes and Stefanie Shapiro; a son, Danny; five grandchildren; and his brother. His marriage to Diane Barnett ended with her death in 2005.
Mr. Reiner’s son Rob Reiner, the actor and director, said Mr. Shapiro had been a nurturer, professionally and personally.
“He loved my dad, he looked up to him — he was like a father to him,” said Mr. Reiner, whose company, Castle Rock Entertainment, produced “Seinfeld.” “George loved being around my dad, and when he started getting older, he’d come over to the house and walk him around the block. That’s the thing you need to know about George: He took care of everybody.”