Open-weight models may undermine AI lab revenue while continuing to feed cloud demand. OpenRouter’s data suggests proprietary models’ share of routed queries fell from roughly 60% to 25% within months. Its routing system directs each request to the lowest-cost model expected to produce an adequate answer, letting open models gain usage without customers selecting them manually. e.g. AT&T is moving a rapidly growing share of its AI work from proprietary models to cheaper open models, and reports cost savings of up to 80%. If other large companies follow, OpenAI and Anthropic could lose much of the routine enterprise usage they currently charge for. FT published a piece