The first half of 2010 was rough on businesses that own patents. Many such firms were swept up in a flood of new lawsuits, thanks to a Federal Circuit ruling in late 2009 that revitalized a previously obscure provision of patent law punishing those who incorrectly mark their products as patented. People seeking to make a quick buck went to court, alleging that businesses had marked their products with incorrect patent numbers and demanding damages of $500 for each wrongly marked item.

A defendant’s potential liability was staggering. Solo Cup Co., for instance, was sued for $10.9 trillion dollars–an amount equal to more than 80 percent of the U.S. national debt.