Anthropic surpassed OpenAI in enterprise AI subscription market share for the first time, reaching 41% in May versus OpenAI's 39.5%, according to Ramp data. Despite Trump administration export controls forcing Anthropic to restrict non-US employee access to core models, the regulatory clampdown unexpectedly boosted sales, mirroring a prior surge after the US Defense Department labeled it a security risk. Anthropic's Claude Opus 4.8 model drives enterprise demand, while OpenAI still leads in consumer markets.