Twitter said Wednesday users are likely to see "follower" numbers drop as the service stops adding in potentially dubious or fraudulent accounts.
The social network said it would make the change by removing from followers any accounts which have been "locked" after sudden changes in behavior, which may signal the people who opened them may no longer be in control.
"This week, we'll be removing these locked accounts from follower counts across profiles globally," Twitter said in a blog post.
"As a result, the number of followers displayed on many profiles may go down."
The San Francisco-based service said it reaches out to owners of locked accounts to confirm all is well and have them reset passwords.
In the meantime, locked accounts were kept in tallies of other Twitter users they "followed."
Twitter said most of these accounts "were created by real people" but that it locks accounts if it cannot confirm that the original person who opened the account is still in charge.
Twitter expected most users to see follower counts ebb by four or less, with "a more significant drop" for people with large follower numbers.
"We understand this may be hard for some, but we believe accuracy and transparency make Twitter a more trusted service for public conversation," the San Francisco-based company said.
Reasons for accounts being locked include tweeting large numbers of unsolicited replies or firing off "misleading" links. Twitter said that it sometimes locks accounts if ranks of users block them, or if stolen passwords are posted online.
"Until we confirm that everything is okay with the account, we lock it, which makes them unable to tweet or see ads," Twitter said.
"In most cases, these accounts were created by real people but we cannot confirm that the original person who opened the account still has control and access to it."
The impetus for the update was that follower counts often serve as an indicator of account credibility, according to Twitter.
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