SEATTLE, United States — Amazon does not breach trade mark rights when it stocks and transports goods for third-party sellers, an adviser to Europe's top court said on Thursday, siding with the US online retail giant against US cosmetics company Coty.

The case is one of the many battles between luxury goods companies seeking to preserve their exclusivity and branding and online platforms such as Amazon and eBay fighting against online sales curbs.

It also raises the question of the scope of online platforms' responsibility for products sold, or content transmitted, on their sites.

The opinion from Manuel Campos Sanchez-Bordona, advocate general at the Court of Justice of the European Union, came in a case involving Coty's German subsidiary, which took Amazon to a German court for stocking Davidoff perfume for third party sellers.

Coty said such practices violate its trade mark rights and that Amazon should be liable for stocking trade mark infringing goods.

Under the scheme called "Fulfilled by Amazon", the US online retail giant stores and transports goods for third-party sellers, a key feature of its business model. The German court subsequently sought guidance from the CJEU.

Companies which are not aware of trade mark infringements cannot be held responsible for storing counterfeit products for third party sellers, Campos Sanchez-Bordona said.

The Luxembourg-based court, which follows such non-binding recommendations in the majority of cases, would normally give a ruling in the next two to four months. Amazon had no immediate comment.

By Foo Yun Chee; editors: Philip Blenkinsop and Mark Potter