SEC.03 / LLM Research
Open-Weight vs Closed AI Models in 2026: Token Volume, Spending Share and When Small Specialised Models Win
Open-weight models now handle most tokens on gateways like Vercel's and OpenRouter, yet closed models still take about 86% of estimated spend. What the September 2026 data shows, why Chinese open models lead, and how a 9B longevity model topped frontier systems on a domain benchmark.