More than 600 million people use Skype to make voice and video calls and send text and audio messages, and there are indications that governments can gain access to these private communications.
Journalists and privacy advocates are urging the company's owner Microsoft to disclose details about Skype user data and possible government efforts to access it, BBC reports.
Reporters Without Borders, the Electronic Frontier Foundation and 43 other campaign groups published a letter Thursday saying the tech giant has been "persistently unclear and confusing" about the confidentiality of Skype conversations.
In May 2011 Microsoft took control of Skype and subsequently expanded its cooperation with U.S. authorities to make online chats and user information more available to police, the Washington Post has previously reported, citing industry and government officials familiar with the changes.
Two years prior Microsoft had already applied to patent technology called “Legal Intercept," which would allow the company to secretly intercept, monitor, and record Skype calls, Computer World has reported.
In May of last year CNET reported that the
The potential spying reportedly expands beyond the boarders of the U.S., as well.
German blog netzpolitik.org recently revealed what it said was a leaked document from Germany's government stating that its law enforcement was working on surveillance software to allow it to track Skype and other data communications.
The coalition that wrote the letter Thursday is asking for the number of requests each government has made and the percentage the firm complies with. It also wants to know Skype user information Microsoft keeps and the firm's analysis on the current ability of third parties to intercept conversations.
The information requested is similar to Google's latest transparency report, which was released on Wednesday and revealed how the U.S. government is able to obtain private users information without a warrant.
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