Privacy advocacy groups, internet activists, journalists and other organisation have urged Microsoft to provide Skype transparency reports on data requests from governments.
45 organisations have signed an open letter to Skype, urging it to be more transparent in efforts to increase data protection.
Electronic Frontier Foundation and Reporters Without Borders have sought a transparency report saying that companies like Google, Twitter and Sonic.net have already released transparency reports.
"Many of its users rely on Skype for secure communications — whether they are activists operating in countries governed by authoritarian regimes, journalists communicating with sensitive sources, or users who wish to talk privately in confidence with business associates, family, or friends."
"It is unfortunate that these users, and those who advise them on best security practices, work in the face of persistently unclear and confusing statements about the confidentiality of Skype conversations, and in particular the access that governments and other third parties have to Skype user data and communications."
A Microsoft spokesperson told the BBC, "We are reviewing the letter."