Longtime Gersh agent Larry Taube has left to become a partner in Principal Entertainment, the management and production firm run by Estelle Lasher, Marsha McManus and Liz Robinson.

Taube spent a decade at Gersh in both its Gotham and L.A. offices.

He will be bringing with him such clients as Michael Cassidy (“The OC”), Brendan Gleeson, Tom Wilkinson, Gale Harold (“Queer as Folk”), “Capote” scribe Dan Futterman and Andy Serkis, who did the acting for Peter Jackson’s Gollum and King Kong characters.

“I’ve been an agent for more than 15 years, and it was time to see how the other half lives,” Taube said of his switch to management.

Principal Entertainment, formed in 1993, has also promoted to partner Meg Mortimer, the founder of Ambrosio/Mortimer and Associates who joined Principal in 2001.

Principal reps a swarm of stage, TV and screen talent on both coasts, including Sandra Oh, Connie Nielsen and Steve Zahn.