Sprint is now allowing some online video to be streamed without counting against customers' data caps, making it the fourth major wireless carrier in the US to implement data cap exemptions or "zero-rating" .
Sprint's first foray into zero-rating, announced last week, is for the Copa America Centenario soccer tournament being held in the US beginning June 3.
Sprint has partnered with FuboTV, a soccer streaming service, to give customers access to every match if they sign up for a 60-day trial.
FuboTV costs $9.99 per month if customers keep it after the trial expires.
While wireless carriers argue that zero-rating benefits consumers, net neutrality advocates say zero-rating gives an unfair advantage to services that don't count against data caps, allowing carriers to favor some content over others.
AT was the first major US mobile carrier to make a big move into zero-rating.