Once a free sign of authenticity and fame, blue ticks must now be bought by subscribers for $8 a month, Twitter says.

Non-paying accounts that had a blue tick lost it on Thursday, as owner Elon Musk implemented a strategy, dubbed “Twitter Blue”, to generate new revenue, announced last year.

Only a tiny fraction of blue-ticked users subscribed — less than 5 per cent of the 407,000 profiles affected, according to Travis Brown, a Berlin-based software developer who tracks social-media platforms.

But on Friday and Saturday, a number of celebrities regained their blue ticks, seemingly without action on their part, including author Stephen King, NBA champion LeBron James, and former US president Donald Trump.

Musk said on Friday that he was “paying for a few (subscriptions) personally.”

American rapper Lil Nas X, whose profile displays the blue tick, tweeted: “on my soul i didn’t pay for twitter blue, u will feel my wrath tesla man!”

The accounts of some dead celebrities, such as US chef Anthony Bourdain, also received a blue tick.

Many official media accounts regained a tick, including AFP, which has not subscribed to Twitter Blue.

The New York Times got back its gold badge this month after Musk had bashed the news organization as “propaganda”.

The Times is among the major media groups that have a gold tick reserved for an “official business account” paying at least $1,000 a month.

The reinstated ticks did not lure back US public radio NPR and Canada’s public broadcaster CBC, which recently suspended activity on their accounts and had not resumed tweeting as of Sunday.

The broadcasters were among those to protest the “state-affiliated” and “government-funded” labels Twitter attached to them, which were previously reserved for non-independent media funded by autocratic governments.

Twitter removed these labels on Friday, including those applied to China’s official news agency Xinhua and Russia’s RT.

‘No means no’

Many who unwillingly gained blue ticks made it clear that they had not subscribed, as the badge became a symbol of support for Musk.

“No means no, boys,” tech journalist Kara Swisher tweeted on Saturday, saying that she had gained the blue tick without her consent.

“Inquiring minds need to know: Does Elon love me for me or for my 1.49 million followers?” she added, two hours after saying she would not pay “$8/month for blue check and meh features.”

The Massachusetts Institute of Technology (MIT), which was also bestowed a blue tick, tweeted Saturday: “We did not subscribe to Twitter Blue.”

Nobel Prize-winning economist Paul Krugman, who last July mocked Musk, saying he had “poor impulse control,” said Saturday: “So my blue check has reappeared. I had nothing to do with that, and am definitely not paying.”

The Twitter, Tesla and SpaceX boss responded with an image of a baby smeared with tomato sauce, crying over his plate of pasta and wearing a bib with a superimposed blue tick.