Sierra AI funding
Sierra Surges to a $10B Valuation After $350M Funding Boost
Sierra, the AI agent startup led by Bret Taylor and Clay Bavor, just hit a bold new milestone. On September 4, 2025, the company announced a $350 million funding round led by Greenoaks Capital, pushing its valuation to an impressive $10 billion—more than double its valuation just last October.