SAN FRANCISCO, Oct 29 (Reuters) - OpenAI is laying the groundwork for an initial public offering that could value the company at up to $1 trillion, three people familiar with the matter said, in what could be one of the biggest IPOs of all time.

OpenAI is considering filing with securities regulators as soon as the second half of 2026, some of the people said. In preliminary discussions, the company has looked at raising $60 billion at the low end and likely more, the people said. They cautioned that talks are early and plans - including the figures and timing - could change depending on business growth and market conditions.