AI startup Sierra raises $950 million at $15 billion valuation

Artificial intelligence (AI) startup Sierra is raising $950 million in a new funding round led by venture capital (VC) firms Tiger Global and GV (formerly Google Ventures), valuing the company at over $15 billion, the startup shared in a blog post on Monday.

The San Francisco-based company said it now has more than $1 billion to invest in expanding its platform and positioning itself as a global standard for AI-driven customer experience transformation.

The round includes participation from existing investors such as Benchmark, Sequoia and Greenoaks. Sierra was founded three years ago by Bret Taylor, chairman of the board of Sam Altman’s OpenAI and former co-CEO of Salesforce, along with former Google executive Clay Bavor.


“We’ve never had such conviction in the opportunity for Sierra and our customers. Just a couple of years ago, we had four design partners. Now, Sierra is serving over 40% of the Fortune 50, and agents built on our platform are powering billions of customer interactions — everything from refinancing homes to processing insurance claims, returning orders, and helping people raise millions in fundraisers,” Taylor wrote in a post on X.

Sierra develops AI-powered customer service agents and is positioning itself within a new class of software companies built on top of foundational models from AI startups such as OpenAI and Anthropic. The company claims that its agents are assembled using over 15 frontier, open-weight, and proprietary models.

Sierra said it has surpassed $150 million in annual recurring revenue since its launch in February 2024. The startup’s enterprise customer base includes companies such as Prudential, Cigna, Blue Cross Blue Shield and Rocket Mortgage, as well as one in three of the world’s largest banks.

The latest funding round comes after the company raised $350 million in additional capital at a valuation of $10 billion, led by Greenoaks, in September last year.