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Types of Patents
There are three types of U. S. patents: utility, design, and plant. The utility patent is the most common type of patent as it is the patent which protects unique inventions. Each type of patent has its own numbering scheme.
Utility patents are completely numerical: 5,146,634
Design patents have the letter D before the number: D339,456
Plant patents have the letters PP before the number: PP08,901
Patents are an important and useful form of literature. The most commonly given reason for performing a patent search is a patentability search for "prior art". However, patent literature can be useful for many other reasons, including:
- To discover new research. Patent information is often available before scholarly literature on a specific technology, if it is published in scholarly literature at all. Corporations rarely publish research outside of patents if it is not publicly funded.
- Since corporations rarely publish their research elsewhere, patents are often the best way to find out about a company's researchers and research activities.
- To find out how something works.
- Patents are highly detailed explanations of a technology or invention. This level of detail is generally not available anywhere else.
- Relevant patents and other related literature are referenced in the very beginning of each patent. Because so much research is done by an inventor and patent examiner prior to patenting, patents are an excellent gateway to literature on a particular technology or invention.
- Patents are historically significant primary documents covering over two centuries of U.S. innovation.
Basic Points of Patent Law
- Patent law was adopted into U.S. law at the country's founding
- U.S. Constitution Article 1, Section 8, Clause 8: "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."
- The specifics of patent law are governed by the Patent Act, a statute passed by Congress
- What can be patented? Generally: Products (machines, manufactures, or compositions), processes, or new & useful improvements upon existing product or processes
- To obtain a patent, an inventor must demonstrate in a patent application that the product or process she has developed is New, Useful, and Non-Obvious
- If a patent is granted, patent protection generally lasts for 20 years