Billionaire Elon Musk has said that his purchase of Twitter would not go ahead unless he was given assurances on the bots he says plague the platform, further complicating his bid for the social media giant.
"Yesterday, Twitter's CEO publicly refused to show proof of <5%," tweeted Musk on Tuesday .
"This deal cannot move forward until he does," said Musk, who has almost 94 million followers on the social network.
Twitter chief executive Parag Agrawal said the platform suspends more than a half-million seemingly bogus accounts daily, usually before they are even seen.
He also said Twitter locks millions more weekly that fail checks to make sure they are controlled by humans and not by software.
Internal measures show that fewer than five percent of accounts active on any given day at Twitter are spam, but that analysis cannot be replicated externally due to the need to keep user data private, Agrawal contended.
Musk said that the real number of bots may be four times what Twitter claims and has said he would make getting rid of them a priority if he owned the platform.
"So how do advertisers know what they're getting for their money?" Musk tweeted in a response to Agrawal about the need to prove Twitter users are real people.
"This is fundamental to the financial health of Twitter."
According to an estimate published Friday by software firm SparkToro, 19.42 percent of Twitter accounts are fake or spam.
However, SparkToro acknowledges its methodology for determining bots is likely different from that used by Twitter.
It also has a tool on its website that shows more than 70 percent of Musk's followers are fake accounts.
The chief of SpaceX as well as Tesla, Musk is currently listed by Forbes as the world's wealthiest person, with a fortune of about $230 billion, much of it in Tesla stock.
Seen by his champions as an iconoclastic genius and by his critics as erratic and power-hungry, Musk surprised many investors in April with news that he wanted to purchase Twitter.