Erven Warnink BV v J Townend & Sons (Hull) Ltd · House of Lords · 1979

Can the Dutch maker stop it?

Short answer: Yes: the name belongs to the real drink.

The facts. A Dutch maker of advocaat, an egg and spirit drink, sold in England for years. A British firm began selling 'Old English Advocaat,' made with Cyprus sherry, which was cheaper to tax. It wasn't a trademark issue.

The ruling. Erven Warnink v Townend (1979): The Lords held a group of traders can protect a name for a distinct product type, extending passing off.

Lawyers still call this the Advocaat case. The law was the same one used to protect Champagne's name in the UK.

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For fun, not legal advice.