Absolutely. Along with the standard, "talk to a lawyer" advice, it's worth noting a few things: 1) Virtually every major technology company includes intellectu

Absolutely. Along with the standard, "talk to a lawyer" advice, it's worth noting a few things: 1) Virtually every major technology company includes intellectual property assignment agreements in the paperwork they require new hires to sign. Most startups probably have the same policy, many perhaps without even knowing it, since its part of plenty of standard paperwork. Y Combinator's standard paperwork includes such a clause. 2) For all of the ones I've seen (and I imagine most respectable companies, and probably every company in California, for reasons to be mentioned), the paperwork claims ownership over anything developed a) during work hours, or b) using company owned equipment, resources, or IP, or c) anything that doesn't fall into the first two categories but that involves an area of business the company is active in, or has plans to be active in. 3) The reason California companies all have roughly the same language, is because those restrictions are what are specified in California state law. Given the nature of California in the tech industry, I would guess that influences what a lot of tech companies use as a general policy. The language is somewhat complicated by the third part of the equation, but generally I believe the company has to be able to show damages in such an instance. 4) There are no such general protections on the federal level, and I believe a majority of states do not offer those protections, meaning that in many states all work, and even in some cases all ideas, that you generate during your employment belong to your employer (if you signed a contract to that effect with the employer).