Twitter's board of directors has agreed to billionaire Elon Musk's $44 billion (£34.5 billion) takeover bid.
Musk, who bid less than two weeks ago, said Twitter has "huge potential" that he will unleash.
He also called for a range of changes, from easing content restrictions to eradicating fake accounts.
The company initially rejected Mr Musk's offer, but now it will ask shareholders to vote to approve the deal.
According to Forbes magazine, Musk is the world's richest man with an estimated net worth of $273.6 billion
Mainly because he holds a stake in Tesla, the electric car maker he runs. He also leads aerospace company SpaceX.
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"Free speech is the cornerstone of democracy, and Twitter is a digital town square
People are here to discuss issues that are vital to the future of humanity," Musk said in a statement announcing the deal.
He added: "I also want to make Twitter better than ever by enhancing the product with new features, making algorithms open source to increase trust, beating spam bots, and authenticating everyone." ”
"Twitter has tremendous potential — I look forward to working with companies and the user community to unlock it."
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The move comes at a time when Twitter is under increasing pressure from politicians and regulators to appear on its platform.
Its efforts to mediate misinformation on the platform have drawn criticism from both the left and the right.
As one of its most notable initiatives
Last year it banned former U.S. President Donald Trump, who may be its most powerful user, on the grounds of the risk of "inciting violence."
At the time, Mr. Musk observed: "A lot of people will be very unhappy with West Coast tech as the de facto arbiter of free speech." ”
Although Trump told Fox News on Monday that he had no plans to rejoin the platform
But news of the acquisition was cheered by the right in the United States.
The man who sent his sports car into space
The White House declined to comment on the acquisition, but spokesman Jen Psaki told reporters: "Regardless of who owns or runs Twitter, the president has long been concerned about the power of large social media platforms. ”
Julian Knight, MP and chairman of the UK Digital, Culture, Media and Sport Committee, tweeted that the deal was "an extraordinary development in the world of social media".
"It will be interesting to see how privately owned Twitter (run by an absolutist person with a free speech attitude) will respond to global regulatory initiatives."
BBC environmental analyst Roger Harabine said scientists were nervous about the potential impact of the acquisition on the climate debate.
He noted that Twitter announced last week that it would ban ads that denied scientific consensus on the climate crisis, and the company acknowledged that misleading information could undermine efforts to protect the planet.
Controversial history
Musk has more than 80 million followers on Twitter, and he himself has a controversial history on the platform.
In 2018, U.S. financial regulators accused him of misleading Tesla investors in tweets
The allegations went unsolved in a $40 million settlement, which Musk continues to deny.
In 2019, he weighed on the platform after a diver involved in rescuing Thai male students for "pedo guy"
Defamation lawsuit – he successfully defeated it.
On Monday, Musk, known for clashing with journalists and critics of the organization, said he saw Twitter as a forum for debate.
"I hope even my worst critics stay on Twitter because that's what free speech means," he wrote hours before the deal was announced.
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As part of an acquisition expected to be completed later this year, Twitter's stock will be delisted and privatized.
Mr Musk said this would give him the freedom to make the changes he wanted to the business.
Among other ideas, he suggested allowing longer posts to be published and introducing the ability to edit them after publishing.
Twitter shares closed up more than 5 percent on Monday after the deal was announced.
But the price is still lower than Musk's offer of $54.20 per share, suggesting Wall Street thinks he's paying too much for the company.
Mr Musk has said he does not "care about the economics of the purchase." However, he will take over a company with mixed financial performance.
Despite its influence, Twitter is rarely profitable, and user growth is slowing, especially in the United States.
Founded in 2004, the company will have $5 billion in revenue by the end of 2021 and 217 million daily users worldwide — a fraction of the numbers generated by other platforms like Facebook.
Bret Taylor, chairman of Twitter's board, said it had fully evaluated Musk's proposal, which was "the best way for Twitter shareholders to move forward."
Image credit, Twitter
Photo caption, Parag Agrawal succeeded Twitter co-founder Jack Dorsey in November
It's unclear who will lead the company forward. Twitter is currently led by Parag Agrawal, who took over last November from co-founder and former boss Jack Dorsey.
But in his offer filing, Musk told Twitter's board: "I don't have confidence in management. ”
Mr. Agrawal told employees on Monday that Twitter's future is uncertain.
According to Reuters, he said: "Once the transaction is completed, we don't know which direction the platform will go." ”
Shareholder voting
Mr Musk's speed at targeting Twitter was staggering. In early April, he became the largest shareholder of the company with a 9.2% stake.
He was subsequently invited to twitter's board of directors but rejected the offer before launching a surprise acquisition of the company on April 14, saying he wanted to "unleash" its potential as a bastion of free speech.
Twitter tried to block his bid, threatening to dilute the stake of anyone who bought more than 15 percent of the company's shares. However, musk's stance shifted after revealing more financial details about his proposed bid.
He has secured $25.5 billion in financing for the deal and will hold a $21 billion stake in the company.
The Board of Directors unanimously approved the Offer, which will now be submitted to shareholders for a vote.
Elon Musk: The new king of Twitter
The speed of the move has caught the attention of many in Silicon Valley.
Somehow, Elon Musk is the absolute monarch of Twitter.
He himself has said that it is not about "economics" but about power and influence.
By taking the company private, he will have full control over Twitter.
He has the right to deal with the company as he pleases. In practice, this would mean more accommodative moderation policies.
He also said he would make his algorithm public — so that people could better understand how Twitter works.
The move opens the door for Donald Trump to return to the platform, though he apparently says he would now prefer to use his own social media platform, Truth Social.
For years, conservatives have argued that Twitter was biased against them — a news that pleases Republicans in the United States.
Without strong platform review, others are disappointed with what Twitter looks like.
You only have to look at how much criticism Facebook has received because they haven't eliminated groups associated with QAnon conspiracy theories or stopped the theft campaign, and you can imagine how much criticism Elon Musk will receive.
The danger for Twitter now is that unfettered freedom of speech on social media can quickly become very ugly.