It's a bit more complicated. A non-compete is enforceable in CA if you own any equity of value that constitutes a loosely defined partnership (http://en.wikipedia.org/wiki/Non-compete_clause#Exceptions_-...). Further you may be blocked from selling the equity for years after leaving, resulting in years of legal non-compete enforcement. It's a messy case, but I've been advised by actual lawyer that when he sees equity structured in certain way it's for no other reason but to make this case.