OpenRouter’s Series B is a bet on model-routing power, not another API aggregation story. The hard number is the jump from 5T to 25T weekly tokens in six months, with a run-rate above one quadrillion tokens this year, 8M developers, and 400+ models. At that scale, OpenRouter sees which models developers swap out, downgrade, or keep as fallbacks inside production agents. That signal is cleaner than most public benchmarks.
The investor list is the tell: CapitalG, NVentures, ServiceNow, MongoDB, Snowflake, and Databricks all have reasons to keep model choice from collapsing into OpenAI, Anthropic, or Google. The catch is margin pressure. If model labs and clouds bundle routing, caching, batch inference, and compliance into enterprise contracts, OpenRouter becomes easier to squeeze. 25T weekly tokens is real leverage; durable leverage needs workflow lock-in, not just throughput.