Is this reasonable or a red flag?
I understand reverse-vesting is useful for multiple founders or a significant Series A. I am a single founder myself, but the term sheet is standardized.
The investor is sophisticated and experienced.
If you have been working on it for sometime, my understanding is that some portion, usually related to total vesting period minus how long you've been working on it, is vested up front. So if you've been working 2 years, then half of you stake Vesta immediately and the other half takes 2 years