Domain seizures are already happening as result of court orders against alleged “counterfeiters”:

After a series of one-sided hearings, luxury goods maker Chanel has won recent court orders against hundreds of websites trafficking in counterfeit luxury goods. A federal judge in Nevada has agreed that Chanel can seize the domain names in question and transfer them all to US-based registrar GoDaddy. The judge also ordered “all Internet search engines” and “all social media websites”—explicitly naming Facebook, Twitter, Google+, Bing, Yahoo, and Google—to “de-index” the domain names and to remove them from any search results.

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“The fight against SOPA [the Stop Online Piracy Act] may be a red herring in some ways,” he notes, “since IP plaintiffs are fashioning very similar remedies in court irrespective of the legislation. Thus, even if SOPA is defeated, it may turn out to be a Pyrrhic victory—opponents may win the battle but may not have gained much as a result.”

via US judge orders hundreds of sites “de-indexed” from Google, Facebook