Frank Zappa's widow is trying to stop a German fan club from using the Grammy-winning rocker's name for its annual "Zappanale" festival.

Gail Zappa says the German-based Arf Society's use of Zappa's name and an accompanying logo infringe on trademarks held by the Zappa Family Trust. The logo features a prominent mustache similar to that sported by the legendary musician.

The Arf Society says the trust has been aware of its use of the name since the festival was launched in 1998.

A state court in Duesseldorf began hearing the case Wednesday.

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