Sierra says it is raising $950 million from new and existing investors in a round led by Tiger Global and GV, giving the company more than $1 billion to keep expanding its enterprise AI platform.

The company’s own announcement describes the valuation only as “over $15 billion,” and that is the safest version to use. TechCrunch separately reported the same round and said the raise pushes Sierra’s post-money valuation above that threshold.

Sierra is best known for AI agents that handle customer-facing work such as support, returns, claims, and sales flows. In the announcement, the company said it now serves more than 40% of the Fortune 50 and that agents built on its platform are powering billions of customer interactions. Those operating numbers come from Sierra itself, so they should be read as company claims rather than independently audited figures.

The funding matters because Sierra is one of the clearest bets that large companies will buy not just models, but full agent systems tied to revenue and customer operations. That makes this more than another generic AI financing story. It is a signal that investors still see room for a dedicated enterprise layer on top of foundation models, especially for workflows where companies want tighter control over brand, compliance, and handoffs to human teams.

The near-term question is whether Sierra can turn that capital into durable adoption before larger platform vendors absorb the same territory.