It will be legally hard for them to "reset the entire equity metrics" if they're using similar ideas and codebase to your company. But if they work on a separa

It will be legally hard for them to "reset the entire equity metrics" if they're using similar ideas and codebase to your company. But if they work on a separate idea not related to the old company, this seems much more possible as then it's the same as them quitting, and then deciding to do another startup. Another issue you need to think about is how much actual drag you'll cause by holding onto your shares. You should give up half your equity if this doubles their chance of succeeding. This seems more likely if you own a large vested chunk like 30% and less likely if you have just vested 10%. Morally, you've put in a certain amount of work already, and it's not like everyone forgot about vesting. The vesting schedule is supposed to be designed anticipating that if someone leaves before vesting is over, the vested amount is kept by the leaver. It seems to make vesting pointless if you know for sure beforehand you'll renegotiate a substantially different amount.