May 11 (Reuters) - OpenAI and Microsoft ( MSFT ) are

rewriting the terms of their multibillion-dollar partnership in

a high-stakes negotiation designed to allow the ChatGPT maker to

launch a future IPO, while protecting the software giant's

access to cutting-edge AI models, the Financial Times reported

on Sunday.

A critical issue is how much equity in OpenAI's new

for-profit business Microsoft ( MSFT ) will receive in exchange for the

more than $13 billion it has invested in the company to date,

the report said. It said Microsoft ( MSFT ) is offering to give up some

of its equity stake in exchange for access to new technology

developed beyond the 2030 cutoff.

They are also revising the terms of a wider contract, first

drafted when Microsoft ( MSFT ) initially invested $1 billion into OpenAI

in 2019, the report said.

OpenAI and Microsoft ( MSFT ) did not immediately respond to Reuters'

requests for comment.

OpenAI has told investors it will share a smaller fraction

of revenue with its largest backer as it moves ahead with

restructuring, The Information reported last week.

In January, Microsoft ( MSFT ) changed some terms of a deal with

OpenAI after entering a joint venture with Oracle and

Japan's SoftBank Group to build up to $500 billion of

new artificial intelligence data centers in the United States.