The Sufficiency of Disclosure requirement lies at the starting-point of patent law. A state or government grants an inventor a monopoly for a given period of time in exchange for the inventor disclosing to the public how to make or practice that invention. For a valid patent to be granted, Sufficiency of Disclosure is an important patent law requirement to be met. An invention must be described in a sufficiently clear and complete manner to enable a person skilled in the art to carry out the invention. The absence of sufficienct disclosure negates the deal, and the patent becomes unenforceable.
In Jerome H. Lemelson case, which was decided in 2005, patents covering bar code readers were held to be invalid because the specification was not complete enough for a person of ordinary skill in the art of electrical engineering to have made and used the claimed invention at the time of the filing date of the original patent application in 1954 without undue experimentation. In other words, there was no Sufficient of Disclosure.
The "best mode requirement" in the United States is an additional requirement complementing the sufficiency of disclosure requirement. That is, the disclosure must also contain the inventor's "best mode" of making or practicing the invention.
The "best mode requirement" only applies to what the inventor knows at the time the application was filed, not as to what was subsequently discovered.
When the description of an invention in a patent or patent application fails to meet the disclosure requirement, it means that the invention is not industrially applicable.
The term "specification" is used to refer to the written description of how to make and use the invention. The specification must be complete enough to enable person of "ordinary skill in the art" of the invention can make and use the invention without undue experimentation.
The term "predictable arts" is used to refer to inventions such as mechanical inventions and software inventions. Predictable arts requires minimum description. A flow chart of a software program is adequate: even source code is not required.
In term "unpredictable arts" is used to refer to inventions in chemistry and pharmaceuticals. Unpredictable arts requires a thoroughly detailed and complete description.