Pro Rata Side Letter (US) by Y Combinator

Updated 17 October 2025

This Pro Rata Agreement grants an investor the right to purchase a pro rata share of Standard Preferred Stock in a future equity financing round. This right is granted in connection with the investor's initial purchase of a Simple Agreement for Future Equity (SAFE) with a Post-Money Valuation Cap. The agreement outlines the calculation of the pro rata share and conditions for termination of this right.

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About this template

What is this template?

Pro Rata Side Letter (US) by Y Combinator is a free, ready-to-use Pre-Seed & Seed Funding template you can open, customize, and download on GitLaw. It gives you a professionally structured starting point, so you never have to draft from a blank page. The wording is plain and modern, organized into clear sections that are easy to read, edit, and adapt to your own situation before you share or sign it.

When should you use it?

Reach for this Pre-Seed & Seed Funding template whenever you need a reliable agreement quickly and want to be sure the essentials are covered. It suits individuals, freelancers, startups, and established businesses alike. Instead of paying for a document drafted from scratch, you can start here, tailor the details to your arrangement, and have a polished draft ready in minutes. Always review the final wording against the laws that apply where you live or do business.

What's typically included?

A well-drafted Pre-Seed & Seed Funding usually sets out the parties involved, the scope of the agreement, and each side's rights and responsibilities. Expect sections covering key terms and definitions, how long the agreement lasts, how it can be ended, and what happens if something goes wrong. This template brings those building blocks together in a sensible order, so you can focus on the specifics rather than worrying about what to include. Open it to read the full document, then sign up to edit, negotiate, and e-sign it directly in GitLaw.

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