Symantec was ordered to pay US$17 million ($A21.8 million) in damages last week after a federal jury in Delaware found it had violated two patents owned by Intellectual Ventures, a major patent licensing company based in the US.
The damages award was far less than the US$298 million (A$382.25 million) Intellectual Ventures had been seeking. The jury also cleared Symantec of infringing a third patent.
Intellectual Ventures, accused Symantec in 2010 of infringing its intellectual property with the security software company's protection products, including Norton antivirus.
The verdict, a blow to Symantec, has confirmed the validity of the patents and strengthens Intellectual Ventures' track record in court.
The multibillion-dollar company has become one of the biggest patent owners in the world and only recently began suing companies in addition to its longtime strategy of licensing its wide array of patents.
Melissa Finocchio, chief litigation counsel for Intellectual Ventures, said in a statement the company was grateful that the jury confirmed the validity of its patents.
"We remain committed to defending inventor rights and protecting the interests of our investors and customers," she said.
A Symantec spokesman said the company was pleased the jury awarded much less than what Intellectual Ventures was seeking and was considering options to further reduce the damages.
Intellectual Ventures sued three other firms at the same time in 2010. Only Symantec and Japan's Trend Micro chose not to settle.