6. Bertrand Serlet

Company: Upthere

At Apple: Brain behind Mac OS

After leaving Apple in 2011, Serlet, one of Apple’s true geniuses, started up a cloud computing company called Upthere with some other former Apple employees. At Upthere, this French researcher is working on to create a cloud OS that will change the way people store their files online.

Serlet was the former Senior Vice President of Software Engineering at Apple Inc. He worked for the release of Mac OS X Tiger, Leopard and Snow Leopard. When Serlet left the company, Apple announced that he is leaving only “to focus less on products and more on science.”