Sierra, the AI agents startup co-founded by tech veteran Bret Taylor, has closed a $350 million funding round led by Greenoaks, catapulting its valuation to $10 billion. This significant capital injection more than doubles the company's valuation from its previous funding round in October 2024, which valued the company at $4.5 billion.
The new funding comes as the AI agents sector continues to attract major investment, following on the heels of other large-scale raises, such as Anthropic's recent $13 billion round.
