patent troll

Meanings

1. A company, person, etc., that owns and enforces patents in an aggressive and opportunistic manner, often with no intention of producing, marketing, or promoting the subjects of the patents.

Etymology

From patent + troll (“in folklore, a grotesque humanoid creature living in caves or hills, or under bridges”), a reference to trolls in folktales who block the path of travellers or threaten to harm them unless some payment is made.