Rebel Fund invests in companies that have been through the Y Combinator accelerator. Its own site states "Rebel aims to invest in the top 10% of startups (top 0.06% of applicants) from Y Combinator" and that it "has unique access to top Y Combinator startups with a nearly 100% deal win rate". On method, the site states "Rebel utilizes a proprietary machine-learning algorithm called Rebel Theorem 5.0 to help validate and screen potential investments, building a diversified portfolio of Y Combinator startups that is statistically powered to outperform." On its relationship to Y Combinator, the same page carries the disclaimer "This website is not sponsored or endorsed by Y Combinator." Rebel is therefore an independent outside fund that invests in YC-accelerated companies and whose partner group is drawn largely from YC alumni founders; it is not part of Y Combinator, not an affiliate of it, and does not claim to be. The firm does not state a sector focus on its site; one partner, Jonathan Hirsch, is labelled on the team listing as covering non-YC biotech.