The news comes a day after the Journal reported that venture-capital firm Thrive Capital would invest around $1 billion in OpenAI, leading the funding round.
OpenAI-backer Microsoft (MSFT.O) is also expected to invest in the firm, the report said.
However, details on how much Apple or Microsoft will invest is yet to be learned, the report added.
Apple and OpenAI did not immediately respond to a Reuters request for comment.
