Microsoft Tops Apple to Become Most Valuable Public Company

In 2019, Mr. Nadella made Microsoft's first of several investments in OpenAI, the start-up that would build the A.I.-powered ChatGPT chatbot. In the end of the summer of 2022, he was impressed by a preview of OpenAI's underlying technology, known as GPT-4, and soon began prodding Microsoft to add generative A.I. to its products at what he called a "frantic pace." He started with adding a chatbot to the Bing search engine, but then began pushing A.I. into the Windows operating system and productive applications like Excel and Outlook, and offering OpenAI's systems to customers of Azure, Microsoft's flagship cloud computing product. The revenue has only just started to show up in Microsoft's financial results. Generative A.I. accounted for about three percentage points of growth to Azure in the three months that ended in September, and the 30-a-month offering inside Microsoft's productivity software began a general release only in November. This isn't the first time that Microsoft has pulled ahead of Apple in recent years.