API Open or Closed? Anthropic and OpenAI's Strategic Choices Worry Enterprise Clients

As they accelerate their push into vertical industry applications, Anthropic and OpenAI are quietly turning API customers into competitors—Canva has already found itself in this situation, while Harvey and Cursor have begun training their own models to mitigate risks. The convergence of three factors—security controls, anti-distillation measures, and first-party applications—is driving the two AI giants to gradually tighten the boundaries of their external API access.