OpenAI also said it was convening an expert panel that will verify any declaration by the company that it has achieved artificial general intelligence.
The company did not share who would serve on the panel when approached by the BBC.
Microsoft will also support OpenAI’s board with the conversion to a for-profit entity, which the company has confirmed boss Sam Altman will not hold an equity stake in, as first reported by Bloomberg.
The original partnership between the companies gave Microsoft rights to much of what OpenAI produced at a time when the startup was hungry for cloud computing resources.
OpenAI has since gone on a deal spree with a host of other major tech players leading to speculation that an AI bubble may be in the offing.
The revised deal extends Microsoft’s rights to OpenAI’s AI models through to 2032 but excludes consumer hardware.
Microsoft’s market cap crossed the $4tn mark on Tuesday for the second time ever after the announcement.
It first reached that milestone in July, following chip designer Nvidia to become just the second publicly-traded company to do so.
