General Catalyst and AMP PBC co-led the round, with strategic investments from NVIDIA and AMD Ventures. River AI describes its goal as personal AI that each person owns and configures themselves.
By the company's own account, what it sells today is an API platform for fine-tuning and building on top of open models. Per Quartz, River AI claims its costs run 2 to 4 times lower than rivals working with closed models. The round was announced on August 11, 2026.