Patents, copyrights and trademarks, as well as trade secrets and related rights, can be used to exclude free riders. These rights are collectively called "intellectual property" or IP.
University of New Hampshire School of Law's Franklin Pierce Center for Intellectual Property
IP Basics: Avoiding Patent, Trademark and Copyright Problems, IP BASICS (UNH Law, Franklin Pierce Ctr. For Intellectual Prop., Concord, NH), Jan. 1, 2015.
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