What Is a Patent

Abstract

A patent, or a letter patent, is an open letter addressed to all whom it may concern. The term was used at first for all grants made by the Crown and was as broad as the king's pleasure. In time, and with the rise of constitutional government, it has been narrowed in meaning. The emphasis has shifted from the first to the second word; the noun "letter" has been retired; the adjective "patent" has come to be a noun. The term now stands for a privilege granted by the Federal Government to an individual. Although the word has not entirely outgrown its original meaning -witness the land patent-it most commonly refers to invention. A patent is, then, the grant by the United States to the inventor of a right in his own invention from which all other persons, so long as the grant runs, are excluded. By statute this right is defined as the right to make, use, and vend. The authority for the grant is a clause in the Constitution. To the Congress is granted the power "to promote the progress of science and useful arts." And the means is specified: "by securing for limited times to inventors the exclusive right to their inventions." The word "patent," be it noted, is not used. The exclusive right is a right, however it may be defined by the Congress, from which all persons save the inventor are excluded. The right is in no sense natural or inalienable. As a gift of the national legislature it is a privilege; it is by the Constitution made an instrument of public purpose. As an incentive its frame of reference is to promote the progress of science and useful arts. This is the condition under which Congress has power to make the grant; this is the end which, if it is to be justified, the grant must serve.