PANews reported on May 5th that, according to CNBC, Sierra, an enterprise AI startup co-founded by OpenAI Chairman Bret Taylor and former Google executive Clay Bavor, has completed a $950 million Series E funding round, valuing the company at $15.8 billion post-money.

This funding round was led by Tiger Global and GV, the venture capital arm of Alphabet, with participation from existing investors including Benchmark, Sequoia, and Greenoaks. Sierra primarily provides AI-powered customer service agents for enterprises, automating customer service and support scenarios.

Sierra's annualized recurring revenue has reportedly surpassed $150 million within eight quarters. Bret Taylor stated that Sierra operates using a "model swarm" approach, combined with its proprietary fine-tuning layers, to provide AI agent services to enterprise clients. Previously, Sierra completed a $175 million funding round in October 2024, valuing the company at $4.5 billion.