The two companies will need to pay Michigan-based z4 nearly $160 million in total penalties for infringing on the company's rights to patents surrounding anti-piracy technologies.

z4's technology provided a method for software to be activated once it is installed. The same technology could also be used to deactivate the software in an effort to deter piracy.

Microsoft was found liable for $115 million in fines and $25 million for willful patent infringement, plus any court costs. Autodesk was ordered to pay $18 million.

Both companies argued that the patents were invalid, and asked for a new trial. That motion was denied in August of last year. The companies went on to appeal the original decision, which was upheld by the US Court of Appeals for the Federal Circuit on November 16.

It is not clear whether the two companies plan to take the case any further, although a Microsoft spokesperson did offer that the decision affected neither Vista nor Office 2007, and no changes would need to be made to XP or Office 2003.

Autodesk and z4 could not be immediately reached for comment.