A judge has ordered Porto to pay nearly 2 million euros ($2.2 million) for releasing internal emails obtained from Portuguese rival Benfica.
The club must also return any documents it still possesses related to the case.
Benfica was seeking nearly 18 million euros ($20.2 million) in damages after a Porto media officer systematically released information from the emails two years ago.
Porto said at the time the emails showed a corruption scheme that benefited Benfica.
Porto said Friday it would appeal the judge's ruling, saying the club only released information the court itself considered to be true.
Benfica released a statement celebrating the decision, which it said protected the privacy of citizens and institutions.
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