Sam Altman highlights co‑founder vesting as the key safeguard: pre‑agree that equity is earned over time, typically a four‑year schedule with a one‑year cliff, so a 50/50 split accrues 25% after year one, 50% after year two, and so on. This simple structure clarifies outcomes if a founder later transitions, keeps the cap table streamlined, and makes fundraising far smoother because investors strongly prefer companies with vested equity. His top advice: set vesting from day one and nurture the pa