Irish ISP UPC said Friday that it will continue to vigorously defend itself against liability proceedings taken against it in the country's courts by music companies. The company is the latest in a series of ISPs to take issue with copyright holders' insistence that they police customers' Internet traffic. Ireland's biggest ISP, Eircom, was successfully taken to court by the IRMA (Irish Recorded Music Association) and is currently sending warning letters to customers who have allegedly infringed copyright through illegal downloading. The IP addresses of those customers are supplied by IRMA, which is using a third-party firm, Dtecnet, to identify customers who are sharing a specific list of its members' copyright works on peer-to-peer networks.UPC said that it does not condone piracy, but considers that "there is no basis under Irish or European law requiring an ISP to monitor or block subscriber traffic on its network." However, the so-called "three strikes" rule -- where customers receive three warnings before their Internet connection is cut off -- features in French and U.K. legislation, where it has met with similar anger from ISPs. In France the HADOPI law has met with criticism from European Digital Rights (EDRI) and the French Data Network (FDN). The law allows a fine and the suspension of the users' Internet connection for one year. Meanwhile in the U.K., the Digital Economy Act adopted earlier this year leaves the door open for similar three-strikes action against Internet users suspected of illegal downloading or file-sharing, although it has not so far been enforced. Many consumer groups have been outraged, and the country's two largest ISPs, BT and TalkTalk, have asked the High Court to carry out a judicial review of the Act, in order to establish whether it contravenes existing privacy laws. The Irish courts will rule on the UPC case on Oct.11.