Stilta Raises $10.5M Seed: AI for Patent Litigation

A five-month-old Swedish startup called Stilta has raised $10.5 million in seed funding. The round was led by Andreessen Horowitz. Stilta, founded in December 2025 by four former McKinsey engineers, develops AI agents for patent invalidity and infringement analysis. The funding also included checks from Y Combinator and founders from various AI companies. This is Stilta's first outside investment. David Haber, an Andreessen general partner, led the round. Stilta's co-founder and CEO, Oskar Block, demonstrated the product. It allows users to input a patent number, and AI agents then search 180 million patents, 250 million scientific publications, and over a trillion archived web pages for prior art. During a demo, the system surfaced 868 prior art references for a wireless-networking patent in about 30 minutes. It mapped these references against claim limitations, color-coding the strength of each read. Users can also prompt agents to draft invalidity theories. This funding highlights the growing investment in AI for patent practitioners.