Switzerland will hand over to Italian prosecutors more documents linked to the investigation of Silvio Berlusconi's media and retail holding company Fininvest.
The Federal Court ruled that the Swiss authorities could pass on information concerning bank accounts allegedly used for fictitious and elevated payments of film and television rights by Mediaset, a firm controlled by the former Italian prime minister's company.
The holders of a number of incriminated Swiss accounts had appealed against the transfer of banking details to the Milan prosecutor's office.
Lawyers for the account holders had argued that an Italian judge had suspended a case against Berlusconi and some of his associates last July because of the statute of limitations.
But the federal court rejected the appeals, stating that other investigations concerning other periods were still under way according to the Italian authorities.
Judicial aid would only be suspended if the Italians dropped their request.
It is a case for which the Italians have made a total of 18 requests for Swiss assistance since 2002. The Swiss authorities froze in 2005 accounts holding more than SFr150 million Swiss francs ($120 million).
The Swiss also have opened their own investigation on suspicion of money laundering in the case, but have disclosed no details.
Berlusconi, named Italy's richest man by Forbes magazine, went on trial in Milan in November along with 11 other people facing charges of false accounting, embezzlement and tax fraud in the purchase of broadcast rights for American movies by Mediaset.
The Italian authorities claim that the media company used offshore companies to artificially increase the cost of broadcast rights, allowing Berlusconi's company to constitute slush funds abroad and lower profits in Italy to pay less tax.
The Milan prosecutor's office, which has had Berlusconi's media empire in its sights since 1996, would also like to investigate payments made to Uefa for the broadcast rights to international football matches.
All the accused have denied wrongdoing. Berlusconi, who has been Italy's premier twice, lost power to Romano Prodi's centre-left coalition in last April's general elections.
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Italian investigators looking into Berlusconi's business dealings have already compiled half a million pages of data.
Three judicial procedures have also been launched against Berlusconi's children for embezzlement and money laundering.
Fininvest is a financial holding company controlled by Silvio Berlusconi's family.
The group is composed of Mediolanum (insurance and banking), Medusa (film production), Mondadori (publishing), AC Milan (football) and Mediaset, which is, at present, the biggest private broadcaster in Italy.
Mediaset owns three channels (Canale 5, Italia 1 Rete 4), a digital television network and other companies related to broadcasting.
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