After buying Twitter, Tesla founder Elon Musk is expected to make some changes to the site - including allowing back those previously banned.
Mr Musk has previously said it was wrong to ban Donald Trump and there has been speculation that other high profile outcasts such as Katie Hopkins could soon return to the site.
The business magnate - who describes himself as a free speech advocate - announced the takeover by writing "the bird is freed", suggesting his view is that the site is overly restrictive.
Since its inception, Twitter has banned a number of high-profile accounts for violating its user policies.
Here are ten people currently serving lifetime bans, but who could be brought back to the site now it is under Mr Musk's ownership.
One of the most high-profile returnees could be the former US president, who was banned in the wake of the Capitol riots in 2021.
Trump had claimed that the US 2020 presidential election had been rigged and many of his supporters rioted and stormed Washington on 6 January 2021.
He was criticised for failing to tell his supporters to stand down.
One of his final tweets read: "The 75,000,000 great American Patriots who voted for me, AMERICA FIRST, and MAKE AMERICA GREAT AGAIN, will have a GIANT VOICE long into the future. They will not be disrespected or treated unfairly in any way, shape or form!!!"
Elon Musk has previously said he would reverse the "foolish" ban on Mr Trump. One of the first decisions he made after completing his takeover of the site was to fire Vijaya Gadde, the head of legal policy, trust and safety, and the person responsible for the Trump Twitter ban.
However, Mr Trump has previously said he would not return to the site, even if given the chance - instead focusing on his own creation, Truth Social.
Read more about Twitter takeover: Super app or 'Wild West'? The future of Twitter under Elon Musk
The right-wing commentator was permanently banned in 2020 for breaching the site's rules on "abuse and hateful conduct".
Hopkins, who first rose to fame in the third series of The Apprentice, became renowned for airing controversial opinions on the platform and was accused of using her account to incite racial hatred.
She criticised the Black Lives Matter movement and sparked a Twitter feud with England football star Marcus Rashford over his successful lobbying over the extension of the free school meal scheme.
The Florida man who shot dead black teenager Trayvon Martin in 2012 - and was subsequently acquitted of all criminal charges - had his account suspended in 2015.
He had used the platform to post semi-nude photographs of a woman he identified as his ex-girlfriend.
Alongside the photos were her name, phone number, and email address. He also accused her of cheating on him with a "dirty Muslim".
His tweets violated Twitter's policy against posting personal contact information or intimate photos without consent, so his account was shut down.
The conspiracy theorist - who claimed 5G mobile phone networks were linked to the spread of COVID - was banned in 2020.
He also believes he is the son of God and the world is run by reptiles (and the Royal Family are all lizards).
Some of his last posts included attacks on the then PM Boris Johnson and Bill Gates.
Such theories were linked to a spate of attacks on 5G masts during the pandemic.
The former English Defence League (EDL) leader was suspended in 2018.
It is believed the far-right figure's profile had violated the platform's policies on "hateful conduct" - but it is not known what triggered the suspension.
Robinson, whose real name is Stephen Yaxley-Lennon, is widely seen as an anti-Islam activist and had more than 400,000 followers on the platform.
His supporters rallied around the hashtag #IAmTommy to protest against the suspension.
He was known as the man whose drug company made huge profits by inflating the price of a lifesaving drug from $13.50 to $750 per pill.
Shkreli, who was chief executive of Turing Pharmaceuticals - later Vyera - said it was capitalism at work and insurance would ensure that people who needed Daraprim got it.
Even Mr Trump was critical of the move, branding him a "spoiled brat".
Shkreli ended up being permanently banned from the site for the targeted harassment of journalist Lauren Duca. The "pharma bro" then served a prison sentence for defrauding hedge fund investors - but was released in May this year.
Right-wing commentator Milo Yiannopoulos was permanently banned by Twitter in 2016 after Ghostbusters actress Leslie Jones was abused by trolls.
The technology editor for US website Breitbart - who called himself "the most fabulous supervillain on the internet" - was accused of encouraging trolls.
The permanent ban led to his fans tweeting the hashtag #freeMilo.
Following his ban, Yiannopoulos appeared at a Republican National Convention fringe event wearing a bulletproof vest and said: "I just got banned from Twitter."
The singer became famous for her offensive Twitter tirades, including hurling racist and homophobic abuse at former One Direction member Zayn Malik.
Eventually, the platform permanently banned her in 2020.
She also made homophobic remarks against Perez Hilton, and the LGBT+ rights charity Glaad.
She refused to apologise, on one occasion writing: "Even if i am a homophobe… so wat? [sic] i still make more $ than u."
The US conspiracy theorist - who founded the website Infowars - was banned four years ago.
Jones has been notorious for claiming the Sandy Hook school attack, one of the deadliest school shootings in US history, was staged by gun control activists using actors - though he has since acknowledged it was real. He ended up being ordered to pay more than a billion dollars in compensation.
In 2017, he apologised after promoting the "Pizzagate" fake story that a Washington pizza restaurant was the locale of a child sex abuse ring run by Hillary Clinton and her campaign chairman, John Podesta, the Washington Post reported.
Donald Trump's former chief strategist was banned from Twitter after he called for the beheading of Dr Anthony Fauci and the FBI director Christopher Wray.
Bannon made the comments calling for medieval violence during a livestream of his talk show and podcast, War Room: Pandemic.
"I'd put the heads on pikes. Right. I'd put them at the two corners of the White House. As a warning to federal bureaucrats: Either get with the program or you're gone," he said.