This monograph is justifiably considered a modern classic. Stephan Kinsella has caused libertarians worldwide to rethink the very basis of intellectual property.Mises warned against patents, and so did Rothbard. But Kinsella goes much further. He argues that the very existence of patents — and copyrights and trademarks, too — is contrary to a free market. They all use the state to create artificial scarcities of nonscarce goods and employ coercion in a way that is contrary to property rights and the freedom of contract.Many who read this book will be unprepared for the rigor of Kinsella's argument. It takes time to settle in, simply because it seems so shocking at first. But Kinsella makes his case with powerful logic and examples that are overwhelming in their persuasive power.After all, the relevance of this argument in a digital age can't be overstated. The state works with monopolistic private producers to inhibit innovation and stop the progress of technology, while using coercion against possible competitors and against consumers. Even US foreign policy is profoundly affected by widespread confusions over what is legitimate and what is merely asserted as property.What Kinsella is calling for instead of this cartelizing system is nothing more or less than a pure free market, which involves nothing resembling what we call intellectual property today. IP, he argues, is really nothing more than a state-enforced legal convention, not an extension of real ownership.Few books written in the last decades have caused so much fundamental rethinking. It is essential that libertarians get this issue right and understand the arguments on all sides. Kinsella's book is masterful in doing just that — making a case against IP that turns out to be more rigorous and thorough than any written on the left, right, or anywhere in between.Read it and prepare to change your mind.To search for Mises Institute titles, enter a keyword and LvMI (short for Ludwig von Mises Institute); e.g., Depression LvMI