Company

Sierra

AI platform that enables enterprises to build, deploy, and manage conversational AI agents for customer experience across web, mobile, phone, and third-party channels like ChatGPT.

Enterprise Software

People

Bret Taylorfounder, co-founder

Funding History

Sep 6, 2025

Sierra raised $350M from Green Oaks at a $10B valuation.

350M
Sep 24, 2025

Sierra raised $350M at a $10B valuation, with Benchmark and Green Oaks as named investors.

350M

Investors

BenchmarkSequoia CapitalGreen Oaks

News

Interviews (3)

Sierra hits $100M ARR in seven quarters and launches GhostWriter — an agent for building agents
6 Apr 2026
Bret Taylor on Sierra's 400-customer surge and publishing AI agents directly to ChatGPT
6 Nov 2025
Bret Taylor on Sierra's $350M raise, beating incumbent SaaS, and the future of AI agents in customer service
24 Sept 2025

News (1)

Sierra raises $350M from Green Oaks at $10B valuation
5 Sept 2025