PATENT THICKETS. ” In a patent thicket, the existence of many overlapping patent claims can cause uncertainty about freedom to operate, impose multiple layers of transaction costs and stack royalty payments beyond levels that can be supported by the value of single innovations. By blocking pathways to market and dampening investor interest in commercialization, a patent thicket has the potential to slow and skew the overall development of new technical applications.””
”
http://www.nature.com/nbt/journal/v25/n4/full/nbt0407-419.html