The parent may be non-profit, but OpenAI LP accepts investments and delivers returns to investors like any other regular company. The only difference is that they 'cap' the returns. However, the cap is negotiated with individuals investor and I haven't seen anything disclosing the cap except for the fact that in the opening round the cap was 100x the initial investment.

100x seems like a pretty generous cap to me.

I'm not a business investor so I can't really tell if x100 is "a lot" or not — Apple and Amazon share prices went up by x500 in the last 20 years, Tesla x200 in the last 10. But how rare is that?

They call them unicorns for a reason.

Are they non-profit? Does receiving $1b investment from a for-profit company still mean you can be non-profit?

Yes to both questions. It's a (set of) specific thing(s) in company law.

https://projects.propublica.org/nonprofits/organizations/810...