The world's second-largest operator of visitor attractions after Disney said on Friday the deal would give it greater scope for "significant, long-term investment" as the Danish interlocking plastic-brick maker expands in China.
The buyers, who already own stakes in Merlin, said that taking it off the stock market, one of the biggest European private equity deals in recent years, would allow the company to invest more in its assets and deliver on growth plans.
"We believe that this group of investors has the unique collective resources necessary to equip Merlin... for their next phase of growth," said Soren Thorup Sorensen, chief executive of Kirkbi, the private investment company of Lego's Kirk Kristiansen family which already holds a 30% Merlin stake.
Lego, known around the world for its colourful plastic bricks, plans to more than double the number of shops in China this year to 140 in its most rapid expansion in any market.
Merlin has three Madame Tussauds in China and said in January it was in advanced talks with third parties about a number of sites for Legoland Parks in the country.
Through efforts to combine its bricks with the digital world, Lego is trying to stabilize its business after sales dropped in 2017 for the first time in a decade.
Shares in Merlin, which also operates The London Eye, rose more than 50% after its 2013 3.5 billion pound London listing to a peak in June 2017, but only seven months later had fallen below the IPO price. They were hit by a rollercoaster accident at Alton Towers in 2015 and the 2017 London terror attacks.
Merlin shares, which closed at 395 pence on Thursday, rose 14% on news of the recommended deal, which values them at 455 pence each, giving the company an enterprise value, including debt, of 5.91 billion pounds ($7.5 billion).
Kirkbi will own 50% of Merlin after the agreed takeover, which is expected to be completed in the fourth quarter, with Blackstone and Canadian pension fund CPPIB owning the rest.
"The Merlin independent directors believe this offer represents an opportunity for Merlin shareholders to realize value for their investment in cash at an attractive valuation," Merlin Chairman John Sunderland said in a statement.
Activist investor ValueAct Capital last month called on Merlin to take itself private given the level of investment needed in the company.
The consortium of buyers said on Friday it recognized "significant, long-term investment is required", a process that will be easier when Merlin is no longer listed.
A source familiar with the matter said an initial, unsolicited offer from the consortium had valued the firm at 425 pence and talks about a takeover pre-dated the ValueAct letter.
Merlin was sold to Blackstone and Kirkbi in 2005, and by the time of the IPO in 2013 had expanded from Europe to four continents and increased visitor numbers ninefold to 54 million.
Last year, it had 67 million visitors at its 120 attractions across 25 countries.