On June 27, Anthropic, OpenAI, and Google captured 97.09% of AI model spend through Vercel's AI Gateway. Open-source model spending has since collapsed to an all-time low over the past five days, according to Vercel CEO Guillermo Rauch.
Key facts
- 97.09% peak spend share for closed models on June 27
- All-time low for open models in past 5 days
- Data from Vercel AI Gateway spanning thousands of developers
- Anthropic + OpenAI + Google combined share
- Rauch: 'Open models spend was barely a thing'
The data, shared by Vercel CEO Guillermo Rauch in a tweet thread on July 2, 2026, tracks real-time inference spending across thousands of developers using the Vercel AI Gateway. The 97.09% share represents the combined spending on Anthropic's Claude, OpenAI's GPT-4o, and Google's Gemini models — the highest concentration of closed-model spend ever recorded through the platform.
"Open models spend was barely a thing," Rauch wrote, describing the June 27 peak. The subsequent five days saw open model spending hit an all-time low, though Rauch did not disclose exact percentage figures for the decline. Vercel's AI Gateway sits between developers and model providers, routing API calls and aggregating usage data across its customer base.
The trend contradicts the narrative that open-weight models like Meta's Llama 3 and Mistral are gaining enterprise traction. Vercel's developer-heavy user base appears to be voting with API calls for proprietary models, likely driven by reliability guarantees and ease of integration. The data does not capture on-premise or self-hosted deployments, which remain a stronghold for open models.
Why this matters
The timing is notable: Meta released Llama 4 in April 2026 and Mistral launched Mistral Large 2 in May, yet neither has dented closed-model spending share on Vercel's platform. The all-time low for open models suggests that even as new open-weight models hit benchmarks, actual production spend remains overwhelmingly proprietary.
Rauch did not specify which open models are included in the data or how Vercel classifies "open models." The company has not published a formal report or methodology for the dataset.
What to watch
Watch for Vercel to publish a formal AI Gateway spending report, expected in Q3 2026, which could reveal exact open-model share percentages. Also track whether Meta's Llama 4 enterprise adoption announcements shift the trend in subsequent months.
