With over 96 million followers on Twitter, billionaire Elon Musk has often voiced his problems about the platform attracting more bots than real humans in its community. 

On Monday, Musk asserted in a securities filing that Twitter was plagued by bots, and that the company had supposedly violated the terms of their merger agreement for failing to show additional evidence of how it monitors and controls the rise of spam and fake accounts.

"Twitter's latest offer to simply provide additional details regarding the company's own testing methodologies, whether through written materials or verbal explanations, is tantamount to refusing Mr. Musk's data requests," a lawyer for the billionaire said in a letter to Twitter.

"Mr. Musk has made it clear that he does not believe the company's lax testing methodologies are adequate so he must conduct his own analysis." 

Musk earlier threatened to put the US$44bn merger deal "on hold" when he challenged Twitter to prove programmed accounts only made up less than 5% of its user population. He believes at least one in every five Twitter users was a bot, Bloomberg reported.

Twitter maintains, however, that it has shared all necessary information "cooperatively" with Musk over its methodologies for tracking spammers and fake users, adding that the company employs real humans who assess the prevalence of bot accounts.

Twitter CEO Parag Agrawal addressed Musk's criticism but insisted not all data could be shared openly because of privacy concerns. "Unfortunately, we don't believe that this specific estimation can be performed externally, given the critical need to use both public and private," Agrawal said last month.

Executives at Twitter also reportedly told staff that Musk could not simply walk away or put the deal on hold over the bot issue since the two parties have signed an agreement to merge. The social media company said it is working to "close the transaction and enforce the merger agreement at the agreed price and terms".