A US Judge has ordered Google, Yahoo, Twitter and Facebook, among others, to delist domain names linked to websites selling counterfeit goods.
It represents a significant step in the ongoing battle against the sale of fake items online.
The case was brought by luxury goods maker Chanel against 600 sites which it had identified as trading in counterfeits.
Many experts were surprised at the scope of the Nevada judge's ruling.
US firm GoDaddy, which manages around 45 million domain names, has been given control of the web addresses of the 600 firms. It has been told to ensure that none of the sites can be accessed.
Judge Dawson also ordered:
- Google, Bing, Yahoo, Facebook, Google+ and Twitter to remove the domain name from any search results pages.
- The defendants to stop using Chanel's name and images, and to stop selling any Chanel products.
- GoDaddy to link the web addresses involved to a site outlining the case.
Chanel's counterfeit investigative team identified the websites by ordering goods from them which it then determined to be fakes.
Writing about the case in his blog, laywer Eric Goldman said: "Wow, I'm sympathetic to the "whack-a-mole" problem rights owner face, but this relief is just extraordinarily broad and is on shaky procedural grounds."
Others have questioned how much jurisdiction the court would have over domains that had been registered outside of the US.
"One of the problems is that the internet is a global phenomenon and you would need similar judgements in all jurisdictions," said Rachel Barber, assistant at law firm Wiggin.
She linked the case to the L'Oreal versus eBay judgement earlier this year.
In July the Court of Justice of the European Union ruled that eBay and others should play a more active role in stopping their sellers from trading in counterfeit L'Oreal goods.
The court said that websites such as eBay might be liable for trademark infringements if they played an "active role" in promoting fake goods.
"It is acknowledged that third party intermediaries are best placed to tackle online infringement and that when intermediaries have knowledge of this based on good evidence that can't just sit on their hands," said Ms Barber.
Google said that it had no comment to make at this stage because it was yet to be served with the judgement. Facebook said was looking into the matter.
Source: BBC Tech News