For the second time this year, a jury has said Vonage Holdings Corp. infringed on patents.

    The jury found Tuesday in federal court in Kansas City, Kan., that Vonage infringed on six Sprint Nextel patents and ordered the VoIP leader pay $69.5 million. Vonage also has to pay Sprint a 5 percent royalty on future revenue, the jury ruled.

    Jurors decided Vonage deliberately infringed on the patents, and U.S. District Judge John Lungstrum can triple the award if he agrees. The jury deliberated on the case, which went to trial on Sept. 4, since Friday.

    Sprint filed the suit two years ago.

    “We are disappointed that the jury did not recognize that our technology differs from that of Sprint’s patents,” Sharon O’Leary, chief legal officer for Vonage, said in a statement. Vonage said it will appeal the ruling.

    Vonage also was found guilty of infringing on three Verizon patents in March and was ordered to pay that company $58 million and a 5.5 percent royalty.

    A judge ordered Vonage to stop signing new subscribers, but the company was awarded a stay on that decision. Vonage has appealed the patent ruling in the Verizon case and a decision is pending.

    In the Sprint case, Vonage claimed that it didn’t use the company’s patents and also disputed the validity of the patents.

    Vonage said in addition to appeals, it will seek to develop workaround technology that won’t infringe on the Sprint patents. The company has pledged the same in the Verizon case.

    Trading of Vonage stock was ceased following Tuesday’s verdict, down 7.7 percent to $1.81.