To mark World Day Against Cyber Censorship on March 12, for just 24 hours, AdBlock replaced many of the banners it would normally remove with messages that clicked through to content from people who governments have tried to silence.

Throughout the day, AdBlock’s 50 million users were shown messages from Amnesty International where ads would usually appear. Messages from Edward Snowden, Ai Weiwei and Pussy Riot were broadcast across the internet.

"We’re showing you Amnesty International banners, just for today, because we believe users should be part of the conversation about online privacy. Tomorrow, those spaces will be vacant again. But take a moment to consider that in an increasingly information driven world, when your right to digital privacy is threatened, so is your right to free expression,” Gabriel Cubbage, CEO of AdBlock says.

“Right now, there are billions of people whose access to internet content is restricted and monitored by their own governments. On the current list of 'Enemies of the Internet' by Reporters Without Borders are China, the United States, North Korea, the United Kingdom, and many others,” he says.

“Remarkably, there are people in the advertising world who would love to convince you that blocking ads is not only censorship, but an attack on diversity. But how is it censorship for an individual person to install an adblocker (or just download a simple text file) because they don’t want to see another banner ad promising 'One Weird Trick To Lose 60 Pounds in Three Days'?"

He went on to explain that it didn’t allow Amnesty’s banners through today, but highlighted how last November, Edward Snowden said “Everybody should be running adblock software, if only from a safety perspective”.

“He mentioned 'safety' because in addition to blocking ads, adblockers can also protect you from malicious or insecure scripts that internet service providers or others may insert into the websites you visit. So as the internet has evolved, adblocking has become a mandatory digital prophylactic against a suite of invisible threats to your online privacy,” AdBlock states.

Governments are avidly seeking the power to control ever greater aspects of online communication, Amnesty International says. The organisation's secretary general Salil Shetty says: “Free speech online is under serious threat as governments seek ever greater powers - through new laws and more intrusive technologies - to control the internet.

"When they are not shutting down websites and arresting bloggers, they are carrying out mass surveillance of our internet use. That is not the internet we want.”

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