The Snowden effect is the increase in public concern about information security and privacy resulting from disclosures that Edward Snowden made detailing the extent of the National Security Agency's (NSA) surveillance activities.
In 2013, Snowden, a former NSA contractor, leaked NSA documents that revealed the agency was collecting data from the electronic communications of United States citizens. Other disclosures included information about PRISM, the agency's data collection program, a surveillance metadata collection and XKeyscore, which supplies federated search capabilities for all NSA databases. Snowden's revelations forced the NSA -- one of the nation’s most secretive organizations-- to publicly explain itself. Since that time, there have been perceptible increases in the general public's knowledge about the U.S. government's cybersecurity initiatives and awareness of how those initiatives have impacted the privacy of individuals, businesses and foreign governments.
The leaks also raised questions about data sovereignty and how secure a company's data really is if it's stored by a cloud provider based in the United States. In 2014, almost 90% of respondents to a survey commissioned by security consultancy NTT Communications said they were changing their cloud-buying behavior as a result of Snowden’s revelations. Just over half said they are carrying out greater due diligence on cloud providers than ever before, and more than four fifths responded that they would seek out more training on data protection laws.
Studies have been conducted to quantify some of the effects as indicated by changes since the Snowden revelations. An Internet poll conducted by the Center for International Governance Innovation showed across 24 countries that, overall, 60 percent of respondents were aware of Snowden; in many developed countries the numbers were higher. Germany came in highest at 94 percent. Sweden, China, Brazil, and Hong Kong percentages were in the mid-to-low eighties. The Canadian number at 64 percent, along with the U.S.'s 76 percent, suggests more media coverage of the events in developed nations outside North America. Behavior changes were reflected in the survey with 43 percent claiming they were more careful about sites they accessed; 39 percent reported changing passwords more often than they had before Snowden's revelations.
In March 2015, Snowden's revelations came to public attention again when Laura Poitras' film about Snowden, Citizen Four, won the Academy Award for best documentary. In May 21015, the U.S. court of appeals ruled that the NSA's mass telephone surveillance was illegal.
See Edward Snowden's TED talk, "Here's how we take back the Internet."