Artificial Intelligence · Profile from AI Research Companion
Sierra
The San Francisco customer-experience agent company founded in February 2023 by Bret Taylor (former Salesforce co-CEO, chair of OpenAI's board since November 2023) and Clay Bavor (18 years at Google), which sells large consumer brands branded AI agents that answer customers by chat, email and voice and take actions such as returns, card replacements and subscription changes. Sierra is the best-known example of outcome-based pricing in AI: customers pay when an agent resolves a case or achieves an agreed result rather than per seat or per token (section 11). It launched publicly in February 2024 and grew unusually fast by its own account: ~$100m of annual recurring revenue (ARR) in seven quarters (November 2025), over $150m entering its third year (February 2026) and "$400M+" by October 2026, having added over $150m in Q3 2026 alone (company blog, 30 October 2026). Its valuation rose from ~$1bn (2024) to $4.5bn (October 2024), $10bn (September 2025) and ~$15.8bn post-money after a $950m Series E led by Tiger Global and GV (May 2026, reported).
At a glance
- Founded
- February 2023, San Francisco, by Bret Taylor (CEO) and Clay Bavor; public launch February 2024
- Headquarters
- San Francisco; offices including New York, London, Paris (expansion announced December 2025), Tokyo (December 2025) (company)
- Ownership / structure
- Private. Investors include Sequoia, Benchmark, Greenoaks, Thrive Capital, ICONIQ, SoftBank Vision Fund 2 (December 2025), Tiger Global and GV (reported). Taylor's stake was reported at ~25% by Forbes (November 2025, reported; verify)
- Leadership (2026)
- Bret Taylor (co-founder, CEO); Clay Bavor (co-founder); Rachel Whetstone (joined March 2025 from Netflix, communications; reported); Dr. Mitesh Patel (head of clinical, October 2026, company); research team behind the τ-bench evaluations (Karthik Narasimhan and others, verify titles)
- AI products
- Agent OS (Agent OS 2.0, November 2025); Agent Studio 2.0 and Agent Data Platform (November 2025); voice agents and Voice Personas (August 2026); Ghostwriter (agent that builds agents, March 2026, expanded September 2026); Explorer (conversation analytics); Horizon long-horizon agents (July 2026); Compliance Console (October 2026); τ-bench evaluation family (from June 2024)
- Scale
- ~$100m ARR (21 November 2025, company); >$150m ARR and first $50m quarter (6 February 2026, company); "$400M+" ARR, >$150m added in Q3 2026 (30 October 2026, company); ~40% of the Fortune 50 (March 2026) and "almost 50%" (October 2026) as customers (company claims; none audited)
- Capital raised
- ~$110m from Sequoia and Benchmark at ~$1bn (announced February 2024, reported); $175m at $4.5bn led by Greenoaks (October 2024); $350m at $10bn led by Greenoaks (September 2025); >$630m raised by April 2026 (TechCrunch); $950m Series E at ~$15.8bn post-money led by Tiger Global and GV (4 May 2026, CNBC; Sierra said "over $15 billion")
- Key partnerships
- Foundation models from OpenAI and Anthropic plus Sierra's own fine-tuned layers ("constellation of models", Taylor, May 2026); SoftBank Corp. as exclusive sales agent in Japan (13 July 2026); Stripe (payments in conversation, October 2026); Google Cloud Marketplace (October 2026); Plaid (2026)
- Signature moves (incl. failures and risks)
- The Taylor–Bavor founding bet (2023); Taylor's OpenAI chair and the dual role (2023); outcome-based pricing (2024); τ-bench and open agent evaluation (2024); the $4.5bn round (2024); the $10bn round and Agent OS 2.0 (2025); acquisitions in Japan, voice, France and long-horizon agents (2026); the $950m Series E (2026); Ghostwriter, "agents as a service" and the $400m ARR claim (2026)
9 strategic moves analysed
Each one gets a full strategy file in the companion: context, the decision, the financing, what happened, and the lesson.
2023
Founding and the Taylor Bavor Bet
Founding / launch
2023
OpenAI Board Chair and the Dual Role
Governance / key role (founder takes outside board chair)
2024
175m Round at 4 5bn
Funding round
2024
Outcome Based Pricing
Pricing
2024
Tau Bench and Open Agent Evaluation
Research / evaluation release
2025
10bn Round and Agent OS 2
Funding round / product launch / revenue milestone
2026
950m Series E at 15 8bn
Funding round
2026
Acquisitions Opera Receptive Fragment Takeoff
Acquisitions (acqui-hire scale) / partnership
2026
Ghostwriter and Agents as a Service
Product launch / strategy statement