After months of delays, Twitter has begun removing its signature blue checkmark from verified users who have not signed up for Twitter Blue, its paid subscription service.

Elon Musk, who launched Twitter Blue last year following his $44 billion acquisition of the social media platform, introduced an $8 per month charge for blue tick and several other features.

Accounts with checkmarks before Musk’s takeover, known as “legacy accounts,” can pay for a subscription after launch or risk losing the check mark, which was initially introduced to prevent impersonation of public figures.

After repeatedly pushing back the April 1 registration deadline, Twitter on Thursday began removing check marks from thousands of old accounts, including high-profile figures such as Pope Francis, Bill Gates and Kim Kardashian.

Prominent organisations, including Human Rights Watch and the NAACP, also lost their check marks, and many tweeted about their decision not to subscribe to Twitter Blue.

Several celebrities took to Twitter to explain that they kept the checkmark without paying.

Numerous government agencies, nonprofits and public service accounts also lost their checkmarks, raising concerns about how the public can distinguish official sources of information from other accounts during public events or emergencies.

Under Musk, verified government accounts were given a grey checkmark, and verified media outlets were given a gold checkmark, though it was unclear how the designations were assigned.

The blue checkmark indicates credibility because it means the platform has verified the user’s identity, helps users identify fake accounts and misinformation, and is mainly reserved for politicians, celebrities, journalists, and media organisations.

Many Twitter users opposed the changes amid concerns that the new system would encourage the spread of misinformation and fake news.

After a wave of impersonation accounts, Twitter was forced to suspend the initial launch of Twitter Blue in early November 2022 but restarted the service in December after making changes.

Removing checkmarks from non-paying customers sparked similar confusion on Thursday, with accounts impersonating public figures such as Jeff Bezos re-emerging, whose fake account announced that the billionaire is “officially shutting down Amazon.”