UPC Ireland is challenging moves taken by Irish record companies which could force it to cut off the internet connections of customers accused of music piracy.
UPC is defending a court action which could compel it to introduce an anti-online piracy system where those suspected of illegally downloading music are warned that they will have their web connections cut off if they continue to do so. The system is called "graduated response".
The court action, which kicked off earlier this month, is being taken by Sony Music Entertainment Ireland, Universal Music Ireland and Warner Music Ireland.
"UPC does not condone piracy and has always taken a strong stance against illegal activity on its network," said a spokeswoman for UPC. "UPC will do everything necessary to comply with its legal obligations but will not voluntarily agree to implement measures such as a graduated response system in the absence of a legal obligation to do so."
The American singer-songwriter Bruno Mars and Barbadian singer Rihanna were among the most pirated artists in 2013.