The direct cost of actions taken by so-called “patent trolls” totalled $29bn (£18.5bn) in the US in 2011, according to a study by Boston University.
It analysed the effect of intellectual rights claims made by organisations that own and license patents without producing related goods of their own.
Such bodies say they help spur on innovation by ensuring inventors are compensated for their creations.
But the study’s authors said society lost more than it gained.
» via BBC