The companies also announced who will lead the new business.
WWE and the company that runs Ultimate Fighting Championship will combine to create a $21.4 billion sports entertainment company.
A new publicly traded company will be formed that houses the UFC and WWE brands, with Endeavor Group Holdings Inc. taking a 51% controlling interest in the new company. Existing WWE shareholders will hold a 49% stake.
The companies put the enterprise value of UFC at $12.1 billion and WWE's value at $9.3 billion.
The new business, which does not yet have a name, will be lead by Endeavor CEO Ari Emanuel. Vince McMahon, executive chairman at WWE, will serve in the same role at the new company. Dana White will continue as president of UFC and Nick Khan will serve as president of WWE.
“Together, we will be a $21+ billion live sports and entertainment powerhouse with a collective fanbase of more than a billion people and an exciting growth opportunity,” McMahon said in a statement on Monday.
The announcement comes after McMahon, the founder and majority shareholder of WWE, returned to the company in January and said that it could be up for sale.
Rumors swirled about who would possibly be interested in buying WWE, with chatter focusing on companies such as Endeavor, Disney, Fox, Comcast, Amazon and Saudi Arabia's Public Investment Fund.
Media industry analysts viewed WWE as an attractive acquisition target given its global reach and loyal fanbase, which includes everyone from minors to seniors and a wide range of incomes.
The company held its marquee event, WrestleMania, over the weekend. Last year, WWE booked revenue of $1.3 billion.
The company is also a social media powerhouse. It surpassed 16 billion social video views in the final quarter of last year. It has nearly 94 million YouTube subscribers and has more than 20 million followers on TikTok. Its female wrestlers comprise five out of the top 15 most followed female athletes in the world, across Facebook, Twitter & Instagram, led by Ronda Rousey with 36.1 million followers.
WWE had more than 7.5 billion digital and social media views in January and February of this year, up 15% from the same time frame a year ago.
The new company plans to trade on the New York Stock Exchange under the “TKO” ticker symbol. Its board will have 11 members, with six being appointed by Endeavor and five being appointed by WWE.
The transaction, which was approved by the boards of Endeavor and WWE, is targeted to close in the second half of the year.
Shares of World Wrestling Entertainment Inc., based in Stamford, Connecticut, fell more than 8% before the opening bell. Shares of Endeavor, based in Beverly Hills, California, rose nearly 3%.