The actual number is under $7 billion. Where is the disconnect? Phillip Mann, of the Mann Law Group, blogged about a New York Times article on July 15, 2013. In that blog he arrived at his $20 billion fee estimate going to defense lawyers.
The NY Times article referenced by Mr. Mann is titled "Has Patent, Will Sue: An Alert to Corporate America." The article is about Erich Spangenberg of IPNav. IPNav is often referred to as a Non-Practicing Entity in patent litigation circles.