Twitter today officially started to crack down on services that allow users to pay for various follow and unfollow automation tactics. Twitter has cut off API access to three of the most prominent “notifications spam” services: ManageFlitter, Statusbrew, and Crowdfire.

The change was first spotted by Matt Navarra. In a statement to TechCrunch, Twitter confirmed the crackdown and said these services have “repeatedly” violated API guidelines. Essentially, the services in question would follow thousands of users automatically, with the idea being some would follow you back.

“We have suspended these three apps for having repeatedly violated our API rules related to aggressive following & follow churn. As a part of our commitment to building a healthy service, we remain focused on rapidly curbing spam and abuse originating from use of Twitter’s APIs.”

ManageFilter is a service that charged users between $12 and $49 per month to automatically find and rapidly follow people “interested in similar topics.” The service’s argument was that following relevant people “is a great way to gain new followers.” After a few days, users could see who followed them back, and unfollow those who didn’t.

Crowdfire charged users $75 per month for auto DM and follow notification features. StatusBrew charged between $25 and $416 per month for similar features:

“Many a time when you follow users, they do not follow back . . . thereby, you might want to disconnect with such users after let’s say 7 days. Under ‘Cleanup Suggestion’ we give you a reverse sorted list of the people who’re Not Following Back.”

With Twitter’s API change, however, all of these services are now rendered useless. Twitter says the developers will be able to “apply for a new developer account and register a new, compliant app,” but the follow/unfollow spam won’t be allowed to continue.

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