July 29 (Bloomberg) -- EBay Inc. is building new software to run its Skype Internet-calling service, a bid to sidestep a licensing dispute with Skype’s founders, who have threatened to take back the underlying technology.

The new software will be expensive and might not work, San Jose, California-based EBay said today in a 10-Q regulatory filing. The company said it might have to shut down Skype if the dispute with the founders isn’t resolved.

The dispute threatens to interfere with plans by EBay Chief Executive Officer John Donahoe to take Skype public in the first half of 2010. EBay bought Skype in 2005, though the rights to some of its so-called peer-to-peer technology remained with the founders. EBay’s plan to create new software is unlikely to work, said Jayanth Angl, an analyst at Info-Tech Research Group.

“It would be quite difficult to replace what they already have as the underlying component to their service,” the London, Ontario-based analyst said. “There are a number of barriers to that, not the least of which are legal barriers.”

EBay, the most-visited U.S. e-commerce site, fell 44 cents, or 2 percent, to $21.40 at 4 p.m. in Nasdaq Stock Market trading. The shares have climbed 53 percent this year.

“Our plans to separate Skype have not changed,” EBay spokesman John Pluhowski said in an e-mail. “We have no comment on the litigation beyond our 10-Q disclosure.”

Lawsuit Over Code

EBay is suing Joltid Ltd., a company owned by Skype’s founders, to prevent them from pulling the technology that runs the service. A trial is scheduled for June.

Joltid has alleged that Skype doesn’t have the rights to certain parts of its software code. Skype is asking the court to declare Joltid’s accusations invalid and make Joltid pay its court costs.

Skype’s IPO is unlikely to happen in the first half of next year, since the trial isn’t slated until June, said Kenneth Henderson, a lawyer at Bryan Cave LLP in New York. He’s not involved in the case.

“Before the IPO, they’ve got to resolve the issue,” said Henderson, who has advised companies on mergers and acquisitions, as well as debt and equity sales. “It will be hard for them to do a successful IPO if there is a serious risk of exposure in this lawsuit.”

Skype, which started in 2002, lets people make calls from their computers to land lines and mobile phones, as well as other computers. It makes money when users call regular phones, set up voice mail and use text-messaging services. Founders Niklas Zennstrom and Janus Friis also created the file-sharing software Kazaa.

Skype’s revenue grew 25 percent to $170 million in the second quarter, EBay reported this month. It has more than 480 million users and is the largest provider of international calls, according to research firm TeleGeography in Washington.

To contact the reporter on this story: Joseph Galante in San Francisco at jgalante3@bloomberg.net

Last Updated: July 29, 2009 18:44 EDT