LinkedIn today filed a motion (PDF) with the US Foreign Intelligence Surveillance Court challenging the gag order that prevents it from revealing government information requests related to national security issues.

The motion was timed with the release of LinkedIn’s semi-annual Transparency Report. Erika Rottenberg, the company’s General Counsel, also published letters to the LinkedIn community and the FBI.

The letter to the FBI notes that LinkedIn has had “numerous conversations” about the issue with the agency and has reached an impasse. As a result, the company has turned to legal recourse by petitioning the FISC. Earlier this month, Google, Yahoo, Microsoft and Facebook filed similar motions over the same issue.

In her letter to LinkedIn users, Rottenberg compared online connections made through its service to a rolodex of contacts and argued that the government should face the same Fourth Amendment restrictions to gain access to data that it faces with physical possessions:

It makes no sense that the technological advancement of our society should reduce the protections offered under the Fourth Amendment. Based on this constitutional principle, we require the government to use the higher standard and obtain a search warrant for access to a member’s connections.

LinkedIn’s latest Transparency Report suggested that very few of its accounts are affected by the government requests that it is allowed to disclose. It received a total of 83 global requests in the first half of 2013, affecting 97 accounts. Of those requests, LinkedIn provided governments with data 49 percent of the time.

LinkedIn’s Commitment to Transparency About Government Requests for Member Data