#4 The Pirate Bay

In April 2009, after The Pirate Bay co-defendants were found guilty of facilitating extensive copyright infringement "in a commercial and organized form", Anonymous launched a coordinated DDoS (distributed denial-of-service) attack against the International Federation of the Phonographic Industry (IFPI), an organisation responsible for safeguarding recording artists' rights. When co-founders lost their appeal against convictions for encouraging piracy, Anonymous again targeted the IFPI, labelling them "parasites." A statement read: "We will continue to attack those who embrace censorship. You will not be able to hide your ludicrous ways to control us."

#3 Megaupload

On January 19, 2012, Megaupload, a website providing file-sharing services, was shut down by the US Department of Justice (DOJ) and the Federal Bureau of Investigation (FBI). In the hours following the shutdown, hackers took down the sites of the DOJ and FBI, as well as the Motion Picture Association of America (MPAA), the Recording Industry Association of America (RIAA), and Broadcast Music, Inc. (BMI) using distributed denial-of-service (DDoS) attacks. Barrett Brown, described as a spokesperson for Anonymous, called the attack "the single largest Internet attack in (Anonymous') history." With the protests against the Stop Online Piracy Act (SOPA) protests only a day old, Brown stated that internet users were "by-and-far ready to defend an open Internet."

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