A developer of cyber-security products that last week saw its $142 million patent infringement judgment against Microsoft upheld is suing the company again, claiming that the software maker is still violating its intellectual property rights.

In court papers filed Thursday, z4 Technologies claims Microsoft has made only an "insignificant change" to the product activation technology over which it first sued in 2004.

At issue in the original case was z4 Technologies' claim that Microsoft's Windows XP and Office products violate patents it holds that govern the use of anti-piracy technology designed to block attempts to use a single password to activate multiple copies of a software program.

A jury sided with z4 in that case, and in 2006 awarded the company $115 million in damages. The trial court later hit Microsoft with $27 million in additional penalties. Last week, a federal court rejected Microsoft's appeal of the decision.

In its latest lawsuit, filed in U.S. District Court for Eastern Texas, z4 claims that Microsoft's new Windows Vista and Office 2007 products contain the same infringements.

Z4 is asking the court for triple damages in the new case because it claims the violation is "willful." Microsoft has yet to file a formal response.

In upholding the verdict in the original lawsuit, the U.S. Court of Appeal rejected Microsoft's claim that one of its products, Brazilian Publisher '98, contained so-called prior art that should have invalidated z4 Technology's patents.

Microsoft failed to meet "the burden of demonstrating by clear and convincing evidence" that BP '98 constituted prior art, the court said. The appeals court also nixed Microsoft's argument that the product keys users need to activate its software are not protected by z4's patents.