The billionaire has bought a stake in the Old Trafford club worth £1.25bn, after Sheikh Jassim bin Hamad Al Thani withdrew his interest to end a long process in which he tried to buy the club outright.
The 71-year-old has a net worth of £12.5bn thanks to the success of global chemicals company Ineos, which has enjoyed massive growth since its founding in 1998, and he will take delegated responsibility for the club's football operations. It will also invest a further US$300m (£236.7m) in the club's infrastructure.
Ratcliffe served as full-time chairman and saw the company go from 400 employees to 26,000 employees and annual revenues of around £52.5 billion.
Ineos has diversified its interests over the years to include consumer brands and sporting interests, which now includes the club that Ratcliffe grew up supporting.
Born in Failsworth in 1952, his “deep-rooted” passion for United grew when he spent the first 10 years of his life in Greater Manchester.
Ratcliffe's family eventually moved to Hull before he went on to study chemical engineering at the University of Birmingham, then gain an MBA from the London Business School.
He began his career at Exxon Chemicals before moving to Courtaulds, and in 1992 he led the acquisition of Inspec Group plc, mortgaging his house to help complete that deal.
Six years later, he bought a factory in Antwerp, Belgium, from Inspec for £84m and founded Ineos, which later became a chemical giant.
Ratcliffe – who was awarded a knighthood in 2018 for services to business and investment – remains chairman of the company, which has developed a diversified sports portfolio in recent years.
The Ineos Grenadiers are a leading professional cycling team, and Sir Ben Ainslie's Ineos Britannia is the record contender for the 37th America's Cup.
The company is the lead partner of the Mercedes Formula 1 team, the performance partner of New Zealand rugby union teams and has backed Eliud Kipchoge's bid to run a sub-two-hour marathon.
Ineos is now looking to take its football ownership to another level, having acquired Swiss Super League side FC Lausanne-Sport in 2017 and taking over the Ligue 1 club two years later.
In 2022, Ratcliffe saw a final £4.25bn bid rejected for Chelsea – a club he had developed a 'divided loyalty' to during his time in London.
The billionaire told the Daily Telegraph in 2018: “I am a season ticket holder at Chelsea. I've been like that for years, even though I'm really a Manchester United fan. Or it was…but things didn't improve (at United).
“It's gone from bad to disastrous. Talk about a glass half empty.”
Things have improved on the pitch recently, but there is a lot of work to do away from it, which is why many United fans are grateful that Ratcliffe has bought a stake in the club.
He said in October 2022 that he “can't sit around hoping that Manchester United will one day become available” after Joel and Avram Glazer indicated to him that they did not want to sell.
But the subsequent announcement that a full or partial takeover of the club could be considered led to a change in objectives, paving the way for Ratcliffe's investment in United.
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