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2165 The Best Mode Requirement

MPEP SECTION SUMMARY This section covers the best mode requirement of the first paragraph or paragraph (a) of 35 U.S.C. 112. If an inventor comes up with a great idea that works well, it would violate the laws of patentability for the inventor to keep the “best mode” of making and using that invention for him/herself. This best mode requirement forces an applicant to express the full disclosure of the claimed subject matter in order to receive a patent. The AIA did not eliminate the best mode requirement, but it does provide that, regarding patent validity or infringement proceedings, the failure to disclose the best mode should not be a basis on which any claim of a patent may be canceled or held invalid or otherwise unenforceable. Please note that this change is only applicable in patent validity or infringement proceedings, an evaluation of an application still includes compliance with the best mode requirement. This section further discusses facts about the best mode including how a specific example of the best mode is not required. Instead, the best mode may be represented by a preferred range of conditions.

  Section Frequency Chart

I. REQUIREMENT FOR A DISCLOSURE OF THE BEST MODE

A third requirement of 35 U.S.C. 112(a) (applicable to applications filed on or after September 16, 2012) is that:

The specification. . . shall set forth the best mode contemplated by the inventor or joint inventor of carrying out the invention.

The third requirement of the first paragraph of pre-AIA 35 U.S.C. 112 (applicable to applications filed before September 16, 2012) is that:

The specification. . . shall set forth the best mode contemplated by the inventor of carrying out his invention.

• The best mode requirement is a safeguard against the desire on the part of some people to obtain patent protection without making a full disclosure as required by the statute.
• The requirement does not permit inventors to disclose only what they know to be their second-best embodiment, while retaining the best for themselves.

Determining compliance with the best mode requirement requires a two-prong inquiry.

• First, it must be determined whether, at the time the application was filed, the inventor possessed a best mode for practicing the invention.
  • This is a subjective inquiry which focuses on the inventor’s state of mind at the time of filing.
• Second, if the inventor did possess a best mode, it must be determined whether the written description disclosed the best mode such that a person skilled in the art could practice it.

II. IMPACT OF FAILURE TO DISCLOSE THE BEST MODE PURSUANT TO THE AIA

Section 15 of the Leahy-Smith America Invents Act (AIA), (September 16, 2011), did not eliminate the requirement in pre-AIA 35 U.S.C. 112, first paragraph, for a disclosure of the best mode, but effective September 16, 2011, it amended 35 U.S.C. 282 (the provision that sets forth defenses in a patent validity or infringement proceeding) to provide that the failure to disclose the best mode shall not be a basis on which any claim of a patent may be canceled or held invalid or otherwise unenforceable.

As this change is applicable only in patent validity or infringement proceedings, it does not alter current patent examining practices as set forth above for evaluation of an application for compliance with the best mode requirement of 35 U.S.C. 112 .

Prior to September 16, 2011, for an invention claimed in a later-filed application to receive the benefit of the filing date of an earlier-filed application, 35 U.S.C. 119(e) and 120 required that the invention claimed in the later-filed application be disclosed in the earlier-filed application in the manner provided by pre-AIA 35 U.S.C. 112, first paragraph.

• Section 15 of the Leahy-Smith America Invents Act also amended 35 U.S.C. 119(e) and 120 to modify this requirement such that the disclosure in the earlier filed application must be made in the manner provided by pre-AIA 35 U.S.C. 112, first paragraph, "other than the requirement to disclose the best mode."
• This change should not noticeably impact patent examining procedure.

 

MPEP SECTION SUMMARY This section covers a few considerations concerning best mode. For example, the examiner must determine what the invention is, updating best mode is not a requirement, and best mode defects cannot be cured through the addition of new matter.

I. DETERMINE WHAT IS THE INVENTION

Determine what the invention is — the invention is defined in the claims.

• The specification need not set forth details not relating to the essence of the invention.

II. SPECIFIC EXAMPLE IS NOT REQUIRED

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.

III. DESIGNATION AS BEST MODE IS NOT REQUIRED

There is no requirement in the statute that applicants point out which of their embodiments they consider to be their best; that the disclosure includes the best mode contemplated by applicants is enough to satisfy the statute.

IV. UPDATING BEST MODE IS NOT REQUIRED

There is no requirement to update in the context of a foreign priority application under 35 U.S.C. 119.

• Furthermore, it is not necessary to update the best mode in applications claiming the benefit of an earlier filing date under 35 U.S.C. 119(e) or 120, which indicate that the disclosure in the earlier filed application must be made in the manner provided by 35 U.S.C. 112(a) or pre-AIA 35 U.S.C. 112, first paragraph, "other than the requirement to disclose the best mode."

V. DEFECT IN BEST MODE CANNOT BE CURED BY NEW MATTER

If the best mode contemplated by the inventor at the time of filing the application is not disclosed, such a defect cannot be cured by submitting an amendment seeking to put into the specification something required to be there when the patent application was originally filed.

 

MPEP SECTION SUMMARY The best mode requirement is a separate and distinct requirement from the enablement requirement of 35 U.S.C. 112(a) or the first paragraph of pre-AIA 35 U.S.C. 112. The best mode provision of 35 U.S.C. 112 is not directed to a situation where the application fails to set forth any mode — such failure is equivalent to nonenablement.

 

MPEP SECTION SUMMARY This section covers the requirements for rejection by the examiner for lack of best mode. The examiner is to assume best mode is disclosed unless evidence points to the contrary.

I. ASSUME BEST MODE IS DISCLOSED UNLESS THERE IS EVIDENCE TO THE CONTRARY

The examiner should assume that the best mode is disclosed in the application, unless evidence is presented that is inconsistent with that assumption.

II. EXAMINER MUST DETERMINE WHETHER THE INVENTOR KNEW THAT ONE MODE WAS BETTER THAN ANOTHER, AND IF SO, WHETHER THE DISCLOSURE IS ADEQUATE TO ENABLE ONE OF ORDINARY SKILL IN THE ART TO PRACTICE THE BEST MODE

According to the approach used by the court in Chemcast Corp.v.Arco Indus, a proper best mode analysis has two components:

• (A) Determine whether, at the time the application was filed, the inventor knew of a mode of practicing the claimed invention that the inventor considered to be better than any other.
  • The first component is a subjective inquiry because it focuses on the inventor’s state of mind at the time the application was filed. Unless the examiner has evidence that the inventors had information in their possession:
    • (1) at the time the application was filed
    • (2) that a mode was considered to be better than any others by the inventors,
      there is no reason to address the second component and there is no proper basis for a best mode rejection. If the facts satisfy the first component, then, and only then, is the following second component analyzed:
• (B) Compare what was known in (A) with what was disclosed - is the disclosure adequate to enable one skilled in the art to practice the best mode?

 

MPEP SECTION SUMMARY In determining the adequacy of a best mode disclosure, only evidence of concealment (accidental or intentional) is to be considered. A few examples of evidence of concealment are covered in this section.

I. EXAMPLES — BEST MODE REQUIREMENT SATISFIED

In one case, even though the inventor had more information in his possession concerning the contemplated best mode than was disclosed (a known computer program) the specification was held to delineate the best mode in a manner sufficient to require only the application of routine skill to produce a workable digital computer program.

II. EXAMPLES — BEST MODE REQUIREMENT NOT SATISFIED

The best mode requirement was held to be violated where inventors of a laser failed to disclose details of their preferred TiCuSil brazing method which were not contained in the prior art and were contrary to criteria for the use of TiCuSil as contained in the literature.

 

» 2171 Two Separate Requirements for Claims Under 35 U.S.C. 112 (b) or Pre-AIA 35 U.S.C. 112, Second Paragraph