Ed Catmull, The Walt Disney Co.‘s top animation executive and co-founder of Pixar, will retire at the end of the year. He will remain as an advisor through July.

Next year will mark 40 years in the industry for Catmull, who started at Lucasfilm before he co-founded Pixar with Steve Jobs.

“I have the mixed emotions that come with stepping away from a group of people I love, but also with the utmost pride and pleasure that we now have at both Pixar and Disney Animation the most dedicated and imaginative leaders I have worked with,” Catmull said.

Disney does not plan to replace Catmull, and instead, the heads of Pixar and Walt Disney Studios will each report to Walt Disney Studios President Alan Bergman.

h/t: Marketwatch