French police raided Vivendi SA's Paris headquarters Oct. 5 in an inquiry into alleged market abuse after it acquired a stake in Mediaset SpA, Reuters reported.

A complaint by former Italian Prime Minister Silvio Berlusconi prompted the search, Vivendi said the same day. Police also searched the Paris offices of bank Natixis, Reuters said.

Vivendi said its Mediaset stake acquisition was conducted "legally and transparently."

Fininvest SpA, the holding company of Berlusconi's family, owns a 39.53% stake in Mediaset.