New Delhi, July 28 -- NEW YORK - When a company guarantees a quarter-trillion dollars of its own customer's lease obligations, it has stopped being a supplier and become something that has no clean precedent in the technology industry.

Nvidia is in early talks with OpenAI to guarantee as much as $250 billion in financing that would allow the AI lab to lease computing capacity from a SoftBank-owned megaproject in southern Ohio, the Wall Street Journal reported Sunday. The arrangement, as described by sources familiar with the negotiations, would make the world's most valuable chipmaker the financial backstop for the lab that spent more than $30 billion in Nvidia hardware in its last fiscal year.

The Ohio campus has been gathering scale f...