Spain's data protection agency has fined La Liga €250,000 ($400,000 AUD) after it was alleged the official La Liga phone app violated EU data privacy and transparency laws.

Spanish online newspaper reported the app allowed the league to remotely activate the phone's microphone to determine whether the owner was in a bar that was screening a La Liga match illegally.

This along with analysing geolocation data was used to protect La Liga's own business interests and find any bars that hadn't paid to screen the match.

According to the Spanish Data Protection Agency (AEPD), this is a violation of transparency principles of the 4 million users of the application.

However, La Liga has stressed that the data could not be used to learn the contents of the conversations and would launch a legal challenge against the fine. 

A La Liga statement said: "We profoundly disagree with this decision, consider the fine that has been imposed to be unfair, and believe the AEPD hasn't made enough effort to understand how this technology works."

"As a result, we will challenge the decision to show that we have always acted legally and responsibly.

"La Liga would not be acting diligently if it did not use all means at its disposal to fight against piracy.

"This is a major undertaking given the scale of the fraud in the market, which is estimated to cost around €400m a year."

The application does ask for permission to access the phones' microphone and location, while the terms of service also detail that users are consenting to La Liga using their phones to detect such behaviour through data received as code rather than audio.

However, the AEPD claims that La Liga has not made these terms of service clear enough and have given the Spanish league a month to correct the violations.