April 24 (Bloomberg) -- Vonage Holdings Corp., ordered to stop adding customers after losing a patent ruling last month, won a request to continue business as usual while it appeals the case. Vonage shares surged as much as 53 percent.

The Internet telephone company won permission from a federal appeals court today to continue signing up new subscribers. A trial judge ordered a ban on new Vonage customers after a jury last month found the company infringed three patents owned by Verizon Communications Inc.

The U.S. Court of Appeals for the Federal Circuit in Washington extended its earlier, temporary stay of the trial judge's ruling just a few hours after hearing oral arguments. The court, which specializes in patent law, also ordered a speedy schedule for the appeal, setting oral arguments for June 25, according to John Thorne, Verizon's deputy general counsel.

``It's business as usual for us,'' said Vonage Chief Executive Officer Jeffrey Citron, in a statement. ``We have not infringed on any of Verizon's technology and remain optimistic that we will ultimately prevail.''

Vonage shares closed up 83 cents, or 29 percent, to $3.72 in New York Stock Exchange composite trading after reaching $4.43. Trading was halted at 1:30 p.m. on news of the order.

It was the biggest one-day percentage jump since Vonage first sold shares to the public in May 2006. More than 25.6 million shares were traded, or 13-times the three-month daily average. Shares of Verizon rose 5 cents to $37.60.

Assure Customers

Today's decision may help assure customers and investors that Holmdel, New Jersey-based Vonage can endure its battle with New York-based Verizon, the second-biggest U.S. phone company.

``They won a battle but they haven't won the war. A lot of damage has been done in the eyes of the public and their subscribers,'' said Patrick Monaghan, an analyst at Boston-based Yankee Group.

To win the stay, Vonage had to convince the court that it has a substantial issue on appeal, or that the harm to the company from lifting the stay outweighs any hardship on Verizon.

``The continuing viability of the company is threatened'' if the stay isn't continued, Vonage lawyer Roger Warin of Washington-based Steptoe & Johnson, told the appeals court. He said there was a ``real risk of insolvency.''

Vonage's appellate brief must be filed with the court by May 9, Verizon's reply is due May 23, and Vonage has until May 30 to reply, Thorne said.

``An appeal could have taken a year or longer; now it will be argued in just two months,'' said Thorne ``We expect the unanimous jury verdict of infringement will be upheld.''

The appeal is Verizon Services Corp. v. Vonage Holdings, 07-01240, U.S. Court of Appeals for the Federal Circuit. The lower-court case is Verizon Services Corp. v. Vonage Holdings, 06-cv-682, U.S. District Court for the Eastern District of Virginia (Alexandria).

To contact the reporter on this story: Jeff St.Onge in the U.S. Court of Appeals for the Federal Circuit in Washington, at jstonge@bloomberg.net.

Last Updated: April 24, 2007 16:38 EDT