Elon Musk and Twitter have always been a volatile combination. That's especially unlikely to change now, with Musk buying a 9.2% stake in the social media company and landing a seat>How much power will Musk have at Twitter?
Musk's piece of Twitter is technically categorized as a "passive" stake, which means it falls just below the 10% threshold for a shareholder to be considered to be an "active" or "activist" shareholder. Typically, passive shareholders don't try to exert much control over a company's decision-making. Musk might be the exception to that rule.
Twitter's board of directors currently has 11 members, with Musk becoming the 12th board member, at least until Dorsey leaves next month. Musk will also control more than 9% of the shareholder votes. Functionally, that means he'll need plenty of support from other board members and shareholders to win their approval for any future proposals.