SCOTTS VALLEY, Calif., July 31 /PRNewswire-FirstCall/ -- VirnetX Holding Corporation (NYSE Amex: VHC) announced today that the United States District Court for the Eastern District of Texas, Tyler Division, issued its patent claim construction, or "Markman" Order ("Markman Order") in the ongoing patent infringement action between VirnetX Inc. ("VirnetX") and Microsoft Corporation ("Microsoft").

In a Markman ruling, a district court hearing a patent infringement case interprets and rules on the scope and meaning of disputed patent claim language regarding the patents in suit. A Markman decision is often a significant factor in the progress and outcome of patent infringement litigation.

In the recently issued Markman Order, the Court adopted interpretations that VirnetX believes are favorable to VirnetX on many of the claim terms that were in dispute in the litigation.

The litigation, which the company previously announced it had filed in February, 2007, involves Microsoft's development and marketing of certain of its products that the company believes infringe three patents owned by VirnetX.

"We are extremely pleased with the Court's Markman Order. We remain confident in our position concerning Microsoft's infringement of the patents at issue," said Kendall Larsen, VirnetX's chairman, president and CEO. "While the outcome of this and any legal matter is unpredictable, we believe the Court's Markman Order is another significant step towards the successful resolution of this litigation and further validates VirnetX's ongoing commitment to the enforcement of our intellectual property and protection of our investment in patent-protected licensing and research and development."