Factors That Should Drive the Split
Equity should reflect expected future contribution, not just who had the idea first. Evaluate each co-founder across five dimensions:
- Idea origination: Who identified the problem and developed the initial solution? This matters, but is usually worth 5–10% premium — not a 2x multiplier.
- Capital contribution: Is any founder putting in personal capital as seed funding? This should be treated as a convertible note or SAFE, not pure equity, to avoid complex tax events.
- Full-time commitment: A founder going full-time from Day 1 vs one who joins after 6 months should receive meaningfully different equity — time-based vesting handles this automatically.
- Domain expertise: Unique, hard-to-replace technical or market expertise (e.g., a regulatory expert in a compliance startup) commands a premium.
- Network value: Direct access to your first 10 enterprise customers or key investors is a real, quantifiable contribution — factor it in.
Common Equity Split Models
Equal split (50/50): Works when both founders have genuinely equal contribution across all five dimensions and have a strong trust relationship. Requires a clear tie-breaking mechanism (usually the CEO has a casting vote on operational decisions). Most common among technical + business co-founder pairs at idea stage.
Majority / minority (60/40): The most common VC-preferred structure. The 60% founder is typically the CEO with the primary vision and external-facing role. Reduces deadlock risk while keeping the minority founder engaged with meaningful equity.
Lead founder model (70/30): Appropriate when one founder is clearly the originator, has prior relevant startup experience, or is taking a materially higher personal risk (e.g., leaving a senior corporate role). The 30% stake is still highly valuable at exit and keeps the co-founder incentivised.