DETROIT (AP) — Elon Musk is threatening to end his $44 billion agreement to buy Twitter, accusing the company of refusing to give him information about its spam bot accounts.

Lawyers for the Tesla and SpaceX CEO made the threat in a letter to Twitter dated Monday that the social platform included in a filing with the Securities and Exchange Commission.

The letter says Musk has repeatedly asked for the information since May 9, about a month after his offer to buy the company, so he could evaluate how many of the company’s 229 million accounts are fake.

A message was left early Monday seeking comment from Twitter.

The lawyers say in the letter that Twitter has offered only to provide details about the company’s testing methods. But they contend that’s “tantamount to refusing Mr. Musk’s data requests.” Musk wants data so he can do his own verification of what he says are Twitter’s lax methodologies.