August 14, 2007
By this notice the Patent Office is formally expressing its position that electromagnetic and acoustic signals are forms of energy and do not contain matter even though the signal may be transmitted through a physical medium. As a result, claims to electromagnetic and acoustic signals do not constitute statutory subject matter within the meaning of the definition of invention in section 2 of the Patent Act.
More particularly, an electromagnetic or acoustic signal is interpreted to be neither an "art" nor a "process" because it is not an act or series of acts or method of operation by which a result or effect is produced by physical or chemical action. Neither is an electromagnetic or acoustic signal a "machine", as it is not the mechanical embodiment of any function or mode of operation designed to accomplish a particular effect, or a "composition of matter", as it is not a chemical compound, composition or substance. An electromagnetic or acoustic signal is taken not to be itself a material product and, therefore, not a "manufacture".
The position taken in this notice pertains to electromagnetic and acoustic signals per se and does not apply to methods, processes, machines or manufactures involved in the generation, transmission, reception, or processing of signals.
The practice expressed in this notice is effective immediately, and supersedes any previously communicated practices related to the patentability of signals.