OpenAI appears to be pulling well ahead of rivals in the race to capture enterprises’ AI spend, according to transaction data from fintech firm Ramp. According to Ramp’s AI Index, which estimates the business adoption rate of AI products by drawing on Ramp’s card and bill pay data, 32.4% of U.S. businesses were paying for subscriptions to OpenAI AI models, platforms, and tools as of April. That’s up from 18.9% in January and 28% in March. Competitors have struggled to make similar progress, Ramp’s data shows. Just 8% of businesses had subscriptions to Anthropic’s products as of last month compared to 4.6% in January. Google AI subscriptions saw a decline from 2.3% in February to 0.1% in April, meanwhile. “OpenAI continues to add customers faster than any other business on Ramp’s platform,” wrote Ramp Economist Ara Kharzian. “Our Ramp AI Index shows business adoption of OpenAI growing faster than competitor model companies.” To be clear, Ramp’s AI Index isn’t a perfect measure. It only looks at a sample of corporate spend data from around 30,000 companies. Moreover, because the index identifies AI products and services using merchant name and line-item details, it likely misses spend lumped into other cost centers. Still, the figures suggest that OpenAI is strengthening its grip on the large and growing enterprise market for AI. OpenAI is projecting $12.7 billion in revenue this year and $29.4 billion in 2026.