a16z exec Steven Sinofsky had murky dealings with Jeffrey Epstein in his previous life working for Microsoft

Steven Sinofsky isn’t a household name outside tech circles, but he once ran the operating system on more than 90% of the world’s PCs, and now quietly sits as a board partner at one of Silicon Valley’s most powerful venture firms, Andreessen Horowitz. He’s also, as Fortune’s new investigation digs into, a former Microsoft insider who turned to Jeffrey Epstein as a seven‑figure fixer on his way out of the company.

Sinofsky joined Microsoft straight out of grad school in 1989 and climbed...