Musk pressures Twitter in the middle of the purchase process 0:45
(CNN) --
Elon Musk wants to back out of a $44 billion deal to buy Twitter, the latest in a whirlwind process in which he became the company's largest shareholder, turned down a board seat, agreed to buy the social media and then began raising doubts about going ahead with the deal.
On Friday afternoon, Musk claimed in a regulatory filing that he is ending the deal because Twitter is "in material breach of multiple provisions" of the original deal, which was signed in April.
Elon Musk threatens to cancel deal to buy Twitter
Musk has for weeks expressed concern, with no apparent evidence, that there are a greater number of bots and spam accounts on the platform than Twitter has publicly said.
Analysts have speculated that the concerns may be an attempt to create a pretext to get out of a deal that it may now see as too expensive.
Twitter did not immediately respond to a request for comment.
This is a developing story.
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