I have a legally registered business, although they were asking me for a specific kind of document to verify my business that I don't have. They also couldn't verify my EIN last time even though it's the one I've been using for years.
I did manage to verify my Stripe account today, but I did so as an individual. It's not ideal, but maybe I'll re-register my business at some point as I think they expect you to have a corporation based on what they were asking for. I can always get a new EIN as well.
Hey, this also means we might finally have Stripe as a payment option here on OO!