Theorem wants to stop AI-written bugs before they ship — and just raised $6M to do it

As artificial intelligence reshapes software development, a small startup is betting that the industry's next big bottleneck won't be writing code — it will be trusting it.Theorem, a San Francisco-based company that emerged from Y Combinator's Spring 2025 batch, announced Tuesday it has raised $6 million in seed funding to build automated tools that verify the correctness of AI-generated software. Khosla Ventures led the round, with participation from Y Combinator, e14, SAIF, Halcyon, and angel investors including Blake Borgesson, co-founder of Recursion Pharmaceuticals, and Arthur Breitman, co-founder of blockchain platform Tezos.The investment arrives at a pivotal moment. AI coding assistants from companies like GitHub, Amazon, and Google now generate billions of lines of code annually.