The deal is believed to be the richest contract an athlete has signed in sports history, topping the 11-year, $325 million (£247 million) slugger Giancarlo Stanton made in 2014 with the Miami Marlins, before he was ultimately traded to the New York Yankees.
The Mexican, who recently dethroned Gennady Golovkin in Las Vegas, has committed his future to the sports streaming service for the next five years and his next 11 fights.
According to Forbes, Alvarez (50-1-2, 34 knockouts), the WBA and WBC middleweight champ, was worth $44.5 million as of July. He reportedly earned $50 million in September for his narrow decision victory over Golovkin.
Alvarez will still be able to fight boxers who are signed with other media partners, provided that those outlets and all other parties can agree on an arrangement.
Canelo’s first fight on the new platform will come on December 15, when he takes on Britain’s Rocky Fielding at Madison Square Garden.
The deal comes in the wake of the news that US network HBO, on whose shows Alvarez previously fought, will stop showing boxing at the end of the year.