Source: https://bitlaw.com/source/mpep/608_01_h.html
Timestamp: 2019-04-25 04:09:07+00:00

Document:
The best mode contemplated by the inventor of carrying out his or her invention must be set forth in the description. See 35 U.S.C. 112. There is no statutory requirement for the disclosure of a specific example. A patent specification is not intended nor required to be a production specification. Spectra-Physics, Inc. v. Coherent, Inc., 827 F.2d 1524, 1536, 3 USPQ2d 1737, 1745 (Fed. Cir. 1987); In re Gay, 309 F.2d 769, 135 USPQ 311 (CCPA 1962). The absence of a specific working example is not necessarily evidence that the best mode has not been disclosed, nor is the presence of one evidence that it has. In re Honn, 364 F.2d 454, 150 USPQ 652 (CCPA 1966). In determining the adequacy of a best mode disclosure, only evidence of concealment (accidental or intentional) is to be considered. That evidence must tend to show that the quality of an applicant’s best mode disclosure is so poor as to effectively result in concealment. Spectra-Physics, Inc. v. Coherent, Inc., 827 F.2d 1524, 1536, 3 USPQ2d 1737, 1745 (Fed. Cir. 1987); In re Sherwood, 613 F.2d 809, 204 USPQ 537 (CCPA 1980).
The question of whether an inventor has or has not disclosed what he or she feels is his or her best mode is a question separate and distinct from the question of sufficiency of the disclosure. Spectra-Physics, Inc. v. Coherent, Inc., 827 F.2d 1524, 1532, 3 USPQ2d 1737, 1742 (Fed. Cir. 1987); In re Glass, 492 F.2d 1228, 181 USPQ 31 (CCPA 1974); In re Gay, 309 F.2d 769, 135 USPQ 311 (CCPA 1962). See 35 U.S.C. 112 and 37 CFR 1.71(b).
If the best mode contemplated by the inventor at the time of filing the application is not disclosed, such defect cannot be cured by submitting an amendment seeking to put into the specification something required to be there when the application was originally filed. In re Hay, 534 F.2d 917, 189 USPQ 790 (CCPA 1976). Any proposed amendment of this type should be treated as new matter.
For completeness, see MPEP § 608.01(p). For a discussion of the best mode requirement see MPEP § 2165 to § 2165.04.

References: v. 
 v. 
 v. 
 § 608
 § 2165
 § 2165