Elon Musk sparred with Twitter Inc. Chief Executive Officer Parag Agrawal over over the prevalence of spam bots on the platform, with the company’s would-be owner saying the number is far higher than acknowledged. 

Musk, who has agreed to buy Twitter for US$44 billion, said last week that he was putting the deal “on hold” until he had more information about how the company measures bot accounts. The billionaire said Monday that he estimates at least 20 per cent of Twitter accounts are actually spam. In a Twitter thread, meanwhile, Agrawal said the number is less than five per cent when measuring daily users -- a figure the company has previously cited in quarterly filings. 

Musk tweeted over the weekend that he was going to run his own test to determine the number of bots on Twitter by sampling 100 random accounts that follow the @Twitter handle. He then tweeted that he picked that sample size because it’s the same sample size Twitter uses to determine its own bot prevalence. 

Agrawal contradicted that claim Monday, saying Twitter has human reviewers look at “thousands of accounts” to determine the prevalence of bots, but added that he couldn’t share more specifics 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 information,” he wrote. 

He added that Twitter shared this methodology with Musk last week.

The issue has emerged as a key concern for Twitter management and investors, with some analysts saying it could derail Musk’s takeover deal -- or knock down the price. Twitter fell as much as 7.9 per cent to US$37.51 on Monday, putting it well below the US$54.20-a-share Musk offer that was approved by the board last month. 

In his Twitter thread Monday, Agrawal said that measuring spam accounts was complicated because some accounts that look like spam are actually real humans, and vice versa. Twitter also allows bots on the service, so simply setting up an automated account is not against the rules. 

Musk was not impressed with Agrawal’s response. He first replied, “Have you tried calling them?” as a way to confirm a user account isn’t spam. Then he simply replied to Agrawal with a poop emoji. 

First, let me state the obvious: spam harms the experience for real people on Twitter, and therefore can harm our business. As such, we are strongly incentivized to detect and remove as much spam as we possibly can, every single day. Anyone who suggests otherwise is just wrong.

— Parag Agrawal (@paraga) May 16, 2022

Some final context: fighting spam is incredibly *dynamic*. The adversaries, their goals, and tactics evolve constantly – often in response to our work! You can’t build a set of rules to detect spam today, and hope they will still work tomorrow. They will not.

— Parag Agrawal (@paraga) May 16, 2022

The hard challenge is that many accounts which look fake superficially – are actually real people. And some of the spam accounts which are actually the most dangerous – and cause the most harm to our users – can look totally legitimate on the surface.

— Parag Agrawal (@paraga) May 16, 2022

Now, we know we aren’t perfect at catching spam. And so this is why, after all the spam removal I talked about above, we know some still slips through. We measure this internally. And every quarter, we have estimated that <5% of reported mDAU for the quarter are spam accounts.

— Parag Agrawal (@paraga) May 16, 2022

Each human review is based on Twitter rules that define spam and platform manipulation, and uses both public and private data (eg, IP address, phone number, geolocation, client/browser signatures, what the account does when it’s active…) to make a determination on each account.

— Parag Agrawal (@paraga) May 16, 2022

Unfortunately, we don’t believe that this specific estimation can be performed externally, given the critical need to use both public and private information (which we can’t share). Externally, it’s not even possible to know which accounts are counted as mDAUs on any given day.

— Parag Agrawal (@paraga) May 16, 2022

For those of you who want to learn more in the meantime: https://t.co/3zShh9dbMjhttps://t.co/njNfHHGrZq

— Parag Agrawal (@paraga) May 16, 2022

So how do advertisers know what they’re getting for their money? This is fundamental to the financial health of Twitter.

— Elon Musk (@elonmusk) May 16, 2022