Niklas Zennstrom and Janus Friis, the founders and creators of Skype, a free application allowing users to place free telephone calls over the Internet, are seeking a private equity firm to help them buy back the company from eBay Inc.

According to reports in the New York Times, the European duo received more than $3 billion for the company in 2005 when they sold it off to eBay Inc.

Skype has more than 405 million registered users, up from 53 million when eBay bought it, and the service had $145 million in revenue in the fourth quarter of 2008.

Calls are free between Skype users, and rates are a few pennies a minute for international calls to non-Skype users; the low cost has helped the company gain 8 percent of the world’s international calling minutes, according to TeleGeography, a market research firm.

Skype controls 8% of the world's international calling minutes, the Times reported.

Analysts say they believe that eBay is looking for a price of at least $1.7 billion, the value of Skype on its balance sheet after the company wrote off a portion of the acquisition in 2007.