The company asked a US appeals court for the retrial on Tuesday, following a Supreme Court ruling in an unrelated patent case on Monday that set a legal precedent for judging the validity of patents.

That request was denied in a brief Court of Appeals ruling late Wednesday, leaving Vonage more or less back where it was last week – facing a potentially length appeals process, albeit this time with some encouraging precedent.

Wednesday’s ruling said that Vonage’s case may not be sent back to the District Court for retrial, but that Vonage is free to cite the new Supreme Court precedent in its appeal.

Vonage was found in March to have infringed upon three Verizon patents that cover some technologies used in both companies’ voice over IP services. An injunction stopping Vonage selling the service was handed down but stayed shortly afterwards.

Vonage believed from the start that it has a strong appeal because of what it says was an overly broad interpretation of Verizon’s patents by the District Court judge.

It now believes that Monday’s Supreme Court ruling in the case of KSR vs Teleflex, relating to a patent on car accelerator pedals, gives it a stronger case to show Verizon’s patents are invalid on grounds of obviousness.