I'm not sure how good this advice is, but I think if I was in your situation, I'd find a Silicon Valley lawyer. They'd have the experience with this kind of is

I'm not sure how good this advice is, but I think if I was in your situation, I'd find a Silicon Valley lawyer. They'd have the experience with this kind of issue, and would understand the various legal, tax, etc, implications. I've used Wilson Sonsini (wsgr.com). I can't say if they're better or worse than others. There are bound to be other suitable firms in NYC, and major entrepreneurial cities worldwide. Of course, this wouldn't be a cheap solution, but perhaps that's ok given the importance of getting this kind of thing right? Good luck!