"This patent is a threat to all Linux vendors and users in the U.S., at least in connection with servers and perhaps also on the client side. If Bedrock defeats Google in court over this patent, it will knock at many doors to collect royalties," says Mueller.

In 2006, Red Hat announced that it offered an additional service for paid subscribers of its Linux products that would indemnify them against lawsuits such as this one. To this day, its website promises, "Red Hat will now provide indemnification as an additional protection in its Open Source Assurance program ... The indemnification further protects against intellectual property infringement claims ... Customers can sign up for Red Hat's expanded Open Source Assurance program by activating their subscriptions (if they haven't done so already), logging into their RHN accounts and accepting the terms of the Open Source Assurance Agreement."

Red Hat could not be reached for comment.

Julie Bort writes the Microsoft Update and Source Seeker blogs for Network World's Microsoft Subnet and Open Source Subnet community sites. Follow Bort on Twitter @Julie188.

in Network World's Software section.