Nokia lost a court case on Friday after a regional court in Mannheim, Germany, found the Finnish mobile phone company had violated patents belonging to German patent firm IPCom.
Nokia spokesman Mark Durrant said the ruling affected phones that were no longer being sold.
We respectfully disagree with this decision, but almost all of these phones predated the grant of the patent in February 2011 and our products today use different methods.
The judgment does not rule whether Nokia's current mobile devices infringe the patent, he said, adding the company would ask a higher regional court to clarify the ruling.
Shares in Nokia, which has been struggling to compete with both high-end smartphone rivals and cheaper competitors, were down 4.8 percent to 2.778 euros ($3.66) at 1128 GMT.
The ruling came the day after Nokia announced a bigger-than-expected loss, dropped its sales chief, and said it would cut more costs.
(Reporting by Helsinki and Frankfurt newsrooms; Editing by Dan Lalor)