OpenAI is releasing a new artificial intelligence model for free, after the company said it would speed up product releases in response to the emergence of a Chinese rival. The startup behind ChatGPT is issuing the AI, called o3-mini, after the surprise success of a rival product by China’s DeepSeek. It will be available without charge – albeit with usage limits – to people who use the free version of OpenAI’s chatbot. DeepSeek rattled tech investors in the US with the release of R1, a so-called reasoning model that underpinned the company’s eponymous chatbot. News that it had topped Apple’s...