(This story was corrected to include a statement from Rates Technology Inc. in the seventh paragraph and one from PatentFreedom in the eighth paragraph.)
For a company that makes no products, Acacia Research (ACTG) spends a lot of time fighting over patents in court. Acacia has filed at least 337 patent-related lawsuits in its 18 years. To make money—sales are expected to rise to $68.8 million this year, from $34.8 million in 2006—Acacia acquires patents from inventors and then seeks fees from companies that it says infringe on those patents. Because Acacia licenses technologies it doesn't design or distribute, it is known as a "nonpracticing entity."