Despite Mr Musk asking a judge to block this from happening, in December, Mr Altman officially released his plans for OpenAI's for-profit arm to take control and "raise the necessary capital" to reach general artificial intelligence.
Elon Musk's bid to buy OpenAI for $97.4bn (£78.7bn) came unsolicited on Monday night and was quickly rejected by his former friend and OpenAI chief executive Sam Altman.
Back in 2015, Mr Musk and Mr Altman founded OpenAI along with nine other Silicon Valley entrepreneurs to ensure "artificial general intelligence benefits all of humanity".
"The Open in openAI means that everyone should benefit from the fruits of AI after it's built, but it's totally OK to not share the science...", wrote former OpenAI chief scientist Ilya Sutskever in an email to Elon Musk in 2016.
When Mr Altman and the others refused to hand over control, Mr Musk left acrimoniously, taking a promised $1bn donation with him, according to OpenAI.