European Union court ruled this week that eBay might become liable for trademark infringements made by its users who sell counterfeit goods under the established global brands if the ecommerce giant is found playing active role in this.

The auction site may also have to actively monitor its customers to ensure their offers for sale are lawful, the court ruled.

The case lodged by L’Oreal relates to allegations of trademark infringement through the sale of branded goods on eBay. One of the complaints filed by the cosmetics company was over the sale on eBay of samples or testers explicitly marked "not for sale." The cosmetics giant also criticized the level of protection offered by eBay against the sale of counterfeit goods and the availability of goods to consumers in the European Union that were meant for other markets.

According to the court ruling EU trademark rules do apply to offers for the sale of goods located outside the bloc if it is clear that those offers target EU consumers.

It said EU national courts should assess if any offer did target EU markets, but that in some cases exemptions from liability offered by EU laws may might not apply.

"When the operator has played an 'active role'... it cannot rely on the exemption from liability which EU law confers, under certain conditions, on online service providers such as operators of Internet marketplaces," the court said in a statement.