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Feb 25 (Reuters) - Amazon's AMZN.O plan to invest up to $50 billion in OpenAI could depend on whether the AI developer goes public or achieves an artificial general intelligence $(AGI)$ milestone, The Information reported on Wednesday, citing people familiar with the matter.

Under terms still being negotiated, Amazon would invest $15 billion upfront, with an additional $35 billion contingent on Microsoft-backed MSFT.O OpenAI hitting an AGI milestone or pursuing an IPO, according to the report.

Additionally, SoftBank 9984.T and Nvidia NVDA.O each plan to invest $30 billion in three installments over the year as part of the funding round, the Information added.

Reuters could not immediately verify the report. OpenAI and Amazon did not immediately respond to a Reuters' request for comments outside regular business hours.

OpenAI is laying the groundwork for an IPO that could value the company at up to $1 trillion, Reuters exclusively reported last year.

Major tech companies and investors are racing to forge partnerships with OpenAI, which is spending heavily on data centers, betting that closer ties with the artificial-intelligence startup would give them a competitive edge in the AI race.

Amazon has been in talks to invest tens of billions of dollars in OpenAI, and the amount could reach $50 billion, a source told Reuters last month.

Investing up to $50 billion could make Amazon the biggest contributor to the AI company's ongoing fundraising round.

(Reporting by Mihika Sharma in Bengaluru; Editing by Sherry Jacob-Phillips)

((Mihika.Sharma@thomsonreuters.com;))