Apple, Google and Facebook may be the headline names among companies involved in a U.S. government surveillance program, but one firm — PalTalk — stands out precisely because it’s so obscure. Here’s a quick look at what PalTalk is, and why it may have piqued the interest of the U.S. government.

What is PalTalk? PalTalk is a voice, video and text chat service. Founded in 1998, PalTalk is actually older than Google or Facebook, and says it was the “first to combine voice and video into instant messaging.”

The company says that it has around 4 million users, and has had up to 70 million downloads to date. That’s not an insignificant number, but certainly not something on the scale of Facebook’s userbase of 1.1 billion.

Last year, the company gained some attention when it snapped up Wilson Kreigel, a Zynga executive who joined the mobile gaming firm through its OMGPOP acquisition. Kreigel is now PalTalk’s President and Chief Operating Officer.

What do they say about PRISM?: Like other firms named in the report, the video and text chat company has denied that it’s involved in the PRISM program.

In a statement to The Washington Post, the company said, “We have not heard of PRISM. Paltalk exercises extreme care to protect and secure users’ data, only responding to court orders as required to by law. Paltalk does not provide any government agency with direct access to its servers.”

Who uses it?: PalTalk prides itself on being a global platform that can support a lot of discussion. It can support up to 5,000 people in one live video chat room, according to its news materials. Basic versions of the service allow users to make chat rooms for up to 200 people at a time. An average of 100,000 users are on the service at any given time, the company has said.

What may have put it on the government’s radar? According to a report from The Washington Post, PalTalk saw “significant traffic” during the Arab Spring and during the ongoing Syrian civil war. PalTalk even garnered a mention in the footnote of a 2009 United Nations counter-terrorism report as a place where people debate material related to al-Qaeda.

Voice-over-Internet Protocol (VoIP) services like PalTalk are often highlighted in government reports as tools that political groups can use to organize and coordinate efforts.

These newer forms of communication have made it more difficult for governments to access messages — something that the Federal Bureau of Investigation calls the “going dark” problem.

As The Washington Post reported, Microsoft’s own VoIP service, Skype, is believed to have made its chats and user data more open to police last year, making it easier to monitor some of those communications.

Related stories:

Innovations: Silicon Valley through the NSA prism

U.S., British intelligence mining data from nine U.S. Internet companies in broad secret program

Wonkbook: These programs might well have been legal. That’s almost worse.

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