Your (and other) replies seem to assume that the startup is something you're already doing on the side, while employed full time doing something else. Is this really that common?? Most, if not all places I've worked assert IP ownership over anything you do while employed, even on your own time. That's 100% what keeps me from moonlighting and/or starting my own thing on nights and weekends, and keeps me from contributing/consulting for friends who want help with their idea. How do you have any confidence that your startup is really yours when you could get sued by a former employer the day you quit to grow it full-time?