• 12.06.12

Why You Might Lose Some Followers On Pinterest Today

Behind the scenes at Pinterest, a group of engineers searches for spam. Today, they’re flipping the switch on their biggest spam purge yet.

Why You Might Lose Some Followers On Pinterest Today

For $300, you can buy 500 Pinterest accounts from Each comes pre-loaded with a few boards, an avatar and an attached Hotmail account. You can’t specify what category your boards will cover or which photos they’ve pinned. But you probably don’t care. Because you, customer, are most likely a spammer.


The account-selling operation promises that you will be “100% satisfied” with their service. Jon Jenkins, the lead engineer at Pinterest, isn’t so sure.

“We pay a lot of attention to those marketplaces and what’s going on there, and we use the information we glean from that to frame our response to how we deal with that stuff,” Jenkins tells Fast Company. “Just because there’s an account that exists on Pinterest doesn’t mean that it has all the same rights and privileges as other accounts.”

Jenkins’s team regularly restricts accounts that it suspects are spammy by, for instance, making their pins unsearchable or removing them from the public feed. On Thursday, it shut down a large swath of such accounts in the biggest and broadest action the site has taken to fight spam on the platform to date.

Because spammers often follow other accounts, in particular high-profile accounts, some Pinterest users will see their follower numbers drop after the mass spam deletion. Jenkins estimates that for about 99% of users, the drop will be less than 10 users.

Pinterest has automated systems and a feature for reporting inappropriate content that it uses to suppress porn and other types of undesirable content. Thursday’s effort, however, specifically focuses on spam that misleads users. It weeds out, for instance, the cookie recipe linked to a weight-loss scam site and the wedding dress photo linked to an ad for a “simple facelift trick” that makes a 57-year-old look 27.

How did Pinterest decide which accounts got the axe? Certainly not by hand. Like Google and other social services, Pinterest employs machine learning experts who have developed an automated process for spotting spammers.

Its system looks at a number of factors, such as IP address, time of day the account user is browsing, the variety of sites from which the account pins and the set of pins viewed over time and compares them to what it has learned about how spammers on the site typically operate. Based on these factors, it decides on a score that ranks the likelihood a particular account is spamming.


Accounts shut down on Thursday score so high on this spectrum that Pinterest didn’t even bother to notify them that their accounts are being shut down. Says Jenkins:

“There’s nobody there to read that email if we send it.”

[Image: Flickr user mafflong]

About the author

Sarah Kessler is a senior writer at Fast Company, where she writes about the on-demand/gig/sharing "economies" and the future of work.