Acadian Ventures is excited to announce our investment in Spine’s $3.0M seed round, alongside a syndicate that includes Y Combinator, Recursive Ventures, Meridian VC, Pioneer Fund, and other seed investors. Spine gives small and mid-size employers free, AI-run payroll, benefits administration, and compliance software — and it’s one of the more interesting business-model inversions, pushing costs away from customers and back to the brokers.
The Problem
Every small business runs into the same choice: pay for an expensive PEO, or hire an in-house HR team to manage payroll, benefits enrollment, and an ever-growing pile of compliance requirements — state registrations, ACA, ERISA, COBRA. Both options are costly, and neither is built for companies ranging from 20 to 200 employees. The result is that the employers who can least afford it end up with the worst benefits infrastructure: manual, expensive, and hard to keep compliant as rules change, often retroactively.
Spine's Approach
Spine's wedge is a monetization model, not just a product one. The software — AI agents that run payroll and people ops, manage benefits enrollment, and maintain compliance on top of an employer's existing HRIS and payroll systems — is free to the employer. Spine gets paid by becoming that employer's broker of record, earning commissions from insurance carriers the same way a traditional broker would, rather than charging a SaaS fee. That structure removes the biggest source of adoption friction for cost-sensitive small businesses, and it produces software-like margins for Spine: roughly 78% contribution margin per client, as modeled by the company.
Layered on top is a healthcare-data flywheel: using first-party usage and claims data to recommend a better-fit, lower-cost health plan at each renewal. If it works as intended, it's the difference between being a broker with an AI front end and being a data business that happens to sell brokerage — and it's the piece of the thesis we're most excited to watch develop.
The Team
Spine was founded in 2025 by Onur Kardesler (CEO) and Ece Cokar (COO), repeat operators building their third company together. That kind of founder-market fit matters here: this is a business that has to operate as a licensed, trusted insurance broker from day one, and that combination of product instinct and operating discipline is hard to fake.
Why We Invested
A team that's shipped before. Second-time founders with a live product and real, if early, revenue traction — commission revenue grew roughly 4.4x over the six months through July 2026 — not just a pitch.
Unit economics that lower adoption friction. Because Spine is paid by carriers rather than employers, the thing that normally slows small-business software adoption — price — simply isn't in the way.
External validation. Spine begins Y Combinator's newest cohort in September 2026 and the company has already landed a number of early customers.
What's Next
Spine is putting the new capital toward its public launch and toward scaling a go-to-market motion built around fractional HR leaders, accountants, and CFOs — the professionals who already sit inside the small businesses Spine is built for. We're proud to back Onur, Ece, and the Spine team. Read more about Spine in their recent YC launch.