Tan founded Sift in Y Combinator's Summer 2011 batch to stop online fraud with machine learning, ran it as CEO for nearly a decade, then moved to executive chairman so he could get back to inventing product.
Jason Tan is founder and executive chairman of Sift, a San Francisco, California digital trust-and-safety company that helps online businesses detect fraud and abuse. He co-founded the company in the Y Combinator Summer 2011 batch and served as CEO for nearly a decade.
Joining Y Combinator When Fraud Was Still Spreadsheets and Rules
Sift started in 2011 as an engineer-led bet that machine learning could keep markets, marketplaces and financial products safer than static rules. Tan has described himself on the Y Combinator company page as an engineer and entrepreneur who likes building products and learning in public, and Sift grew into a category leader used by hundreds of brands.
Passing the CEO Baton to Get Back to Building
In January 2021 he told the company he was handing the CEO role to then president and COO Marc Olesen and becoming founder and executive chairman. "I was born a jazz musician but today's Sift needs an orchestra conductor as CEO," he wrote in a public letter on the Sift blog, saying he wanted to return to inventing technology rather than running a large operating organization.
Staying Close to Strategy and Moonshots
As executive chairman he said he would stay involved in board alignment, long-term strategy, capital decisions and a small exploratory "moonshots" team inside Sift. Of the 64 startups in his YC class, he noted that only a handful were still going a decade later, and he framed the succession as a step toward a company that outlives any single founder.
