Very interesting finding that a client brought to my attention today regarding javascript style rollover menus. They got a call from their legal dept that they need to change the manner in which their rollover menu is activated (at the risk of having to pay license to continue using the navigation technique). Its no April fools joke, apparently this is really happening.

Apparently a company named Webvention LLC has obtained enforcement rights to a patent, U.S. Patent No. 5,251,294 - "Accessing, assembling, and using bodies of Information."

A menu link, that when rolled over, expands to show a list of categorized, related links. Dropdown menus and slide-out menus are examples of this patented navigational methodology. A key component of this patent is that the dropdown/slide-out action must be initiated by a rollover or mouseover event. If the dropdown/slide-out action is initiated by any other event, such as a mouse-click event, then this behavior is not in violation of the patent.

Anyone ever heard of this or know of the validity of its claims? Website is here: http://www.webventionllc.com/