According to a release filed with the SEC, Musk will join the board of directors after taking a 9.2% stake in the company.

In premarket trading, shares were up more than six percent.

It was clear to the CEO that he would bring great value to the Board after having conversations with him.

He is both a passionate believer and intense critic of the service, which is exactly what we need in order to be stronger in the long-term.

Musk's term is set to end in 2024, according to the filing. For his entire board term or 90 days after, Musk cannot be the beneficial owner of more than 14.9% of the company's common stock.

Musk's purchase comes after he criticized the company. Last month, the CEO of the electric car company asked people on the social networking site if it followed free speech principles. He said he was considering building a new social media platform.

Musk said on Tuesday that he would push for adjustments after he was named to the board.

Musk said that he was looking forward to working with the board to make improvements to the site.

Musk's stake, the largest among outside shareholders, is considered a passive interest, which means the holder isn't trying to control or influence the company. Some investors expected Musk to be aggressive.

Hours after his holding in the company was revealed, Musk took to social media to ask users if they wanted an edit button. The post urged people to vote carefully, as the consequences will be important.

This is breaking news. You can check back for updates.