The normal way for start founders to receive equity, is only from one or more of these 3 things:
- For hours worked, based on the vesting and usually the hours must be beyond the cliff or you get nothing.
- If you built a crucial part of the IP that the company needs to buy from you with equity.
- Cash invested up front - less common.
He fulfilled none of those. Not even close to being a cofounder. Ideas aren't included among those.