US patent

Under United States law, a patent is a right granted to the inventor of a (1) process, machine, article of manufacture, or composition of matter, (2) that is new, useful, and non-obvious. A patent is the right to exclude others from using a new technology. Specifically, it is the right to exclude others from making, using, selling, offering for sale, importing, inducing others to infringe, and/or offering a product specially adapted for practice of the patent.

United States patent law is authorized by the U.S. Constitution. Article One, section 8, clause 8 states:

The Congress shall have power ... To promote the progress of science and useful arts, by securing for limited times to authors and inventors the exclusive right to their respective writings and discoveries;

Patent law is designed to encourage inventors to disclose their new technology to the world by offering the incentive of a limited-time monopoly on the technology. This limited-time term of patent is 20 years from the earliest patent application filing date (but this term can be extended via patent term adjustment). After the patent term expires, the new technology enters the public domain and is free for anyone to use.

Patent law is found under Title 35 of the United States Code. The "patentability" of inventions (defining the types things that qualify for patent protection) is defined under Sections 100-105. Most notably, section 101 sets out "subject matter" that can be patented; section 102 defines "novelty" and "statutory bars" to patent protection; section 103 requires that an invention must not only be new, but also "non-obvious".

"Whoever invents or discovers any new and useful process, machine, manufacture, or composition of matter, or any new and useful improvement thereof may obtain a patent therefor, subject to the conditions and requirements of this title." 35 U.S.C. 101. To be patent eligible subject matter, an invention must meet two criteria. First, it must fall within one of the four statutory categories of acceptable subject matter: process, machine, manufacture, or composition of matter. Second, it must not be directed to subject matter encompassing a judicially recognized exception: laws of nature, physical phenomena, and abstract ideas.

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