OpenAI has picked two law firms, Cooley and Wachtell Lipton Rosen & Katz, to prepare for an initial public offering that could come as soon as this year, according to people familiar with the matter.

Selecting lawyers to prepare for a listing is one of the first concrete steps the ChatGPT maker has made towards a public listing and usually precedes other measures, such as appointing investment banks to advise on the process. A public listing from OpenAI—which is being valued at $730 billion in an ongoing funding round, before the $110 billion investment—would rank as one of the biggest IPOs of all-time and could allow ordinary investors to get a stake in the pioneer of the AI boom.