(Adds deeal's financial advisers, details)
July 11 (Reuters) - Talent agency WME-IMG said on Monday it would buy mixed martial arts promoter Ultimate Fighting Championship (UFC) in a transaction a source valued at $4 billion, making it the world's biggest ever sports deal.
The deal involving the global sports powerhouse is backed by private equity firms Silver Lake Partners LP and KKR & Co LP as well as investment firms owned by billionaire Michael Dell and his family.
Founded in 1993, UFC holds more than 40 fights around the world every year. These events, which feature mixed martial arts derived from a Brazilian form of fighting, are broadcast in more than 156 countries, reaching 1.1 billion households.
WME-IMG did not provide the terms of the deal in a statement, but a source confirmed the deal values the mixed-martial arts franchise at around $4 billion. Previously, the largest sports deal was Liberty Media Corp's purchase of the Atlanta Braves in 2007 for $2.4 billion, according to Thomson Reuters data.
UFC's parent Zuffa LLC, which gets its name from the Italian word for "fight," is controlled by casino moguls Frank and Lorenzo Fertitta. The Fertitta brothers, who bought UFC for $2 million in 2001, will hold a passive minority stake in the company after the transaction closes.
UFC Chief Executive and Chairman Lorenzo Fertitta will no longer be involved in the company's day-to-day operations and Dana White will remain its president, WME-IMG said.
The deal comes a day after the franchise hosted UFC 200, one of the biggest events in its history, at the T-Mobile Arena in Las Vegas.
Reuters reported in May that the franchise drew interest from a number of parties including WME-IMG, Chinese firms China Media Capital and Dalian Wanda Group, and U.S. private equity firm Blackstone Group LP.
Barclays, Credit Suisse and Deutsche Bank, Goldman Sachs and KKR Capital Markets advised the buyers and provided financing for the deal while The Raine Group and JP Morgan Chase & Co were financial advisers to the sellers of UFC.
Reporting by Narottam Medhora and Anya George Tharakan in Bengaluru; Editing by Kirti Pandey and Tom Brown