Ya, renegotiate now. I was in the exact a similar situation 4 years ago, same exact split. Co-founders we're both neurosurgeons from an ivy league. The company was medical related, but not really. Them being neurosurgeons brought nothing to the table except connections to other doctors.
Long story short, I worked 6 months, they sat around being neurosurgeons all day. They found a buddy to invest seed round at a poor valuation, basically sold the company.
My mistakes were: working on it too long without an agreement, not asking for enough when we did get an agreement, poor negotiation when seed was being done, and not knowing their motives for doing a company. They wanted a check box for their resume, not to run a business (despite what they told.me and themselves)
If you're the engineer in a startup that's at all "technical", rather than a thin business layer over a CRUD db, then you're where the business is and the other two are remote!
> It is 20%-40%-40%. 20% for me for now because I work remotely.
I have trouble following the logic there. If your remote status means you're significantly less valuable / productive than someone local (to the other founders), they should replace you with a local hire.
But if you're a right person for the job, then I can't think of any principled reason for you to accept less than 1/3, protected ownership of the company.
That being said, because this is a business relationship, IMO you're best served by viewing this dispassionately as a negotiation. It's hard to justify a particular level of ownership for you as being "fair", similarly to how it's hard to justify a particular price for a commodity as being "fair". So you might consider the following goal instead: try to maximize your equity + salary, within the constraints of (a) dealing honestly, and (b) keeping it a win-win-win proposition for you and the other two owners.
And, as others have said, prior to renegotiating, give some serious thought to the ways your 20% can become 0%. Even if your still in the honeymoon period with the other founders, there's a decent chance they, or other investors, will try to strip that away from you in the future. It sucks, but it's one of the painful lessons of startup life. Monetary stress or greed can turn many persons into unbelievable jerks.
I second this. It sounds like you're getting ripped off, especially if you're the only developer. You'll basically be the one to deliver the product or initiate it.
Bail. You've done all the 'actually succeeding at stuff' by producing the MVP, they've done none of the actually succeeding at stuff by raising finance. Sorry :(
To clarify, in other responses, he has specified he won't be hiring anybody except with equity offers because there is not enough financing until they get revenue.
Bail. They haven't raised enough money or presold enough product.
What exactly does that mean? Do you expect your stake to go up or down in the future? Do you have it in writing that has been reviewed by your own lawyer? Because the reality may be 0%-50%-50% and you just don’t realise yet.