There are two types of “reduction to practice”:
- actual reduction – this occurs prior to filing the application when the inventor is able to build a physical embodiment of the claimed invention; and
- constructive reduction – when a patent application is filed and the filing serves as conception and constructive reduction to practice of the subject matter described therein.
The patent statute does not contain any express requirement that an invention must be reduced to practice before it can be patented. Neither the statutory definition of the term in §100 [USC] nor the basic conditions for obtaining a patent set forth in §101 [USC] make any mention of “reduction to practice.” Pfaff v. Wells Elecs., Inc., 525 U.S. 55, 60-61 (1999).
The inventor therefore need not provide evidence of either conception or actual reduction to practice when relying on the content of the patent application, as with items generally presumed capable of reproduction (e.g., some type of table).