An attorney can help you work through the mechanics of your situation, some additional things to keep in mind (while you're getting materials to talk to them be

An attorney can help you work through the mechanics of your situation, some additional things to keep in mind (while you're getting materials to talk to them because really, do that first): 1. Try talking to someone who you trust & who is totally unconnected (maybe a family member) and get an alternative and more charitable interpretation of the other founders' actions. In the end you may not believe it but it's a useful perspective. 2. Only work with people you like and trust. From the sound of it whatever the legal options you probably don't want to keep working with this team. 3. Founder equity is not worth much if you don't also have a continuing role in the company (leverage) or a strong relationship with the remaining founders (trust). There are many things that can happen in future financing that are highly dilutive and if protecting your interests is not seen as essential your 30% could end up not worth a lot (or readily liquid). Cash in any amount is probably more valuable. 4. Even if you legally can use the IP for a new company doing so could give the current team ammunition to take shots at your reputation. Good luck.