How to Split Equity Among Co-Founders
by Michael Seibel · Y Combinator
Michael Seibel argues for equal or near-equal founder equity, working through the standard justifications for uneven splits — idea origination, prior work, timing — and treating four-year vesting with a one-year cliff as the real protective mechanism.
More resources on Finding Co-Founders
The First Deal: The Division of Founder Equity in New Ventures
Hellmann and Wasserman model founder equity division as costly bargaining and test it on 1,476 founders across 511 ventures. About one third split equally, and quick equal splits predict lower valuations at first financing. The only rigorous empirical treatment of the equity-split question rather than opinion.
The Founder's Dilemmas: Anticipating and Avoiding the Pitfalls That Can Sink a Startup
Wasserman analyzes roughly 10,000 founders and 3,600 startups to map early decisions about co-founders, roles, rewards, and control. Documents why friend-based teams show higher turnover and why fast equal equity splits track with worse financing outcomes.
The Founder Dating Playbook
Gloria Lin documents the five-stage process she ran across six candidate partners over a year: sourcing, exploratory chats, a two-week joint prototype, a fifty-question alignment questionnaire discussed over several sessions, and an explicit commit-or-part decision.
10 Questions to Discuss with a Potential Co-Founder
Y Combinator's discussion template: ten questions partners should resolve before committing — equity, roles, decision rights, commitment level, exit expectations — plus supplementary questions and a checklist of steps to complete when formalizing the partnership.
How To Find A Co-Founder
Y Combinator group partner Harj Taggar covers why solo founding is harder, when to bring a partner on, where to look beyond your existing network, and how to sustain the relationship once the team forms. Covers the full arc (why, when, where, maintain) rather than a single tactic.