MILAN (MF-Dow Jones)--Italian unlisted holding company Telco's shareholders Thursday decided to appeal the ruling of a Brazilian regulator on Tim Brazil, a person with knowledge of the situation said Thursday.

Holding company Telco - which includes Italian banks Intesa Sanpaolo (ISP.MI), Mediobanca SpA (MB.MI), insurer Assicurazioni Generali (G.MI) and the Benetton family as well as Spanish phone giant Telefonica SA (TEF) - holds 24.5% of Italy's largest telecommunications operator, Telecom Italia (TIT.MI).

Last week Brazilian market authorities asked Telco to launch a bid for the minorities of its Brazilian unit TIM Participacoes SA (TSU). Telecom Italia holds 81.3% of ordinary shares in TIM Participacoes, Brazil's third-biggest mobile-phone operator and one of the Italian phone group's core markets. A buyout of the minorities in TIM Brazil could cost Telco's shareholders up to EUR500 million, according to analysts' estimates based on the ordinary shares value.

The same person said an independent Telco advisor made a fairness opinion on the value of Telecom Italia shares placing its value at EUR2.20. According to press reports Telco shareholders may decide to write down the value of their investments in Telecom Italia.

-By Alessandro Mocenni with MF-Dow Jones and Sabrina Cohen, Dow Jones Newswires; +39 02 5821 9906; sabrina.cohen@dowjones.com

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