OpenAI is preparing to confidentially file for a U.S. initial public offering in the coming weeks, a source familiar with the matter said on Wednesday, adding to a wave of blockbuster ‌listings anticipated in the year ahead.

The plan by the ChatGPT maker, which was last valued at $852 billion, comes two days after it fended off an existential court challenge from Elon Musk and threatens to upstage SpaceX's IPO filing, expected later in the day.

"Resolving that legal overhang removed a major obstacle to an IPO and likely gave OpenAI the confidence to accelerate its timeline," IPOX Vice President Kat Liu said.

OpenAI is aiming to go public as early as September and is working with Goldman Sachs and Morgan Stanley on a draft IPO prospectus that it plans to file with the regulators soon, according to two sources.

Liu said timing its filing close to SpaceX's IPO takes some of the scrutiny off of OpenAI and allows the company to tell its own story. "Simultaneous filings also force portfolio managers to evaluate both companies side by side."

OpenAI did not immediately respond to a Reuters request for comment. The Wall Street Journal first reported on the AI company's plans earlier in the ‌day.

The Sam Altman-led company was laying the groundwork to go public in an offering that could value it at up to $1 trillion, Reuters had reported in October, with the aim to raise at least $60 billion at the low end in preliminary discussions.

AI's revolutionary use cases have unleashed an investor frenzy in names believed to emerge as key winners from wider adoption of the technology.

OpenAI, which helped pioneer the widespread consumer adoption of generative AI models, had raised $122 billion earlier this year, likely marking Silicon Valley's largest-ever funding round.

But in recent months, it has revised its product roadmap twice as it grapples with fierce competition from rivals, first Google and then Anthropic.

Anthropic, which has cemented its lead in the enterprise AI market, is expected by some industry watchers to surpass OpenAI's revenue growth in the months ahead.

ChatGPT serves more than 900 million weekly active users, OpenAI said earlier this year, adding that it had surpassed 50 million consumer subscribers.