Sierra, the fast-growing AI agent startup, is close to raising $350 million in new funding, with Greenoaks Capital expected to lead the round, according to Axios. The deal would value Sierra at an impressive $10 billion, highlighting the rapid rise of AI-driven enterprise solutions.

Founded in 2023 by Bret Taylor, former Salesforce co-CEO and current OpenAI chair, along with ex-Google executive Clay Bavor, Sierra develops AI-powered chatbots designed to manage enterprise-level customer service. Its clients already include major names like Weight Watchers and SiriusXM, signaling strong adoption across industries.

The company is also projected to surpass $100 million in annual recurring revenue (ARR), underscoring the strong demand for scalable AI agents. In its last round in October 2024, Sierra raised $175 million at a $4.5 billion valuation, also led by Greenoaks, with participation from Thrive Capital and Iconiq.

Sierra’s momentum reflects the broader shift toward AI agents as a cornerstone of enterprise transformation. In June, the company noted that 15% of its customers generate over $10 billion in annual revenue, while nearly half generate more than $1 billion, underscoring its focus on large-scale enterprises.

With Microsoft, OpenAI, and even Elon Musk’s xAI entering the AI agent race, Sierra’s latest funding round positions it as a formidable player in shaping the future of enterprise customer support automation.