How did they possibly lose this case? This could easily destroy Disney's bottom line because people will purchase sling for 1 day for only for sports events instead of a monthly subscription.
Per TFA:
Disney argued that the passes violate an agreement with Sling TV that says the service must give subscribers access to its content through monthly subscriptions.
However, Judge Subramanian argues that this claim isn’t likely to succeed, as the contract doesn’t stipulate a “minimum subscription length,” adding that the agreement’s “broad definition” of a subscriber “clearly covers users of the Passes.”
Seems Disney never though a streaming service would offer anything less than monthly subscriptions and thus did not did not clearly define a minimum subscription length; and thus Sling could sell one day subscriptions. IIRC, if a contract is not clear the benefit goes to the one who did not write the contract, in most cases. I suspect Disney will fix this in the next contract, or look to see if generates marginal revenue without hurting subscription revenue and decide it's OK. Sling also probably would not have offered it if they though it would have a negative long term impact on subscriptions and subscriber growth.,