35 USC 112

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35 USC 112

Section 112 deals generally with requirements of the Specification.  Specifically, it provides:

(a) In General.— The specification shall contain a written description of the invention, and of the manner and process of making and using it, in such full, clear, concise, and exact terms as to enable any person skilled in the art to which it pertains, or with which it is most nearly connected, to make and use the same, and shall set forth the best mode contemplated by the inventor or joint inventor of carrying out the invention.

(b) Conclusion.— The specification shall conclude with one or more claims particularly pointing out and distinctly claiming the subject matter which the inventor or a joint inventor regards as the invention.

(c) Form.— A claim may be written in independent or, if the nature of the case admits, in dependent or multiple dependent form.

(d) Reference in Dependent Forms.— Subject to subsection (e), a claim in dependent form shall contain a reference to a claim previously set forth and then specify a further limitation of the subject matter claimed. A claim in dependent form shall be construed to incorporate by reference all the limitations of the claim to which it refers.

(e) Reference in Multiple Dependent Form.— A claim in multiple dependent form shall contain a reference, in the alternative only, to more than one claim previously set forth and then specify a further limitation of the subject matter claimed. A multiple dependent claim shall not serve as a basis for any other multiple dependent claim. A multiple dependent claim shall be construed to incorporate by reference all the limitations of the particular claim in relation to which it is being considered.

(f) Element in Claim for a Combination.— An element in a claim for a combination may be expressed as a means or step for performing a specified function without the recital of structure, material, or acts in support thereof, and such claim shall be construed to cover the corresponding structure, material, or acts described in the specification and equivalents thereof.[1]35 U.S.C. § 112.

Usually, a 112 rejection relates to one of paragraphs 1-4.  As such, each of these paragraphs will be analyzed separately.

Part (a)

The first subpart of section 112 deals with three aspects: written description, enablement, and best mode.  To satisfy the written description, the Specification must clearly show the invention that is claimed.  Keep in mind that no new matter can be added to the Specification after it is filed.  As such, the written description must be sufficient on its own without any additional matter added to satisfy this requirement.

To argue this issue, the test to apply is one of possession: “a patent specification must describe the claimed invention in sufficient detail that one skilled in the art can reasonably conclude that the inventor had possession of the claimed invention.”[2]M.P.E.P. § 2163(I).   Additionally, during prosecution, a claim may be amended and trigger a 112 paragraph 1 rejection.  Usually, the issue is whether there was “adequate support” for the amendments in the Specification, or whether “new matter” was added by the Amendment.[3]M.P.E.P. § 2163(I).   In the case of adequate support, direct the Examiner to the specific provisions in the Specification where support is shown.  Additionally, with respect to the “new matter” rejection, show support in the Specification where such matter is indicated.  If the “new matter” is indeed new material, then it would need to be taken out as it would be in violation of 35 U.S.C. § 132.

One additional thing to note is that the determination of whether a written description is sufficient is made on a case-by-case basis.[4]See e.g., In re Wertheim, 541 F.2d 257, 262 (CCPA 1976).   Additionally, there is a presumption that the description as filed is adequate until the Examiner presents evidence to the contrary.[5]See, e.g., In re Marzocchi, 439 F.2d 220, 224 (CCPA 1971).

The test for enablement has been explained as such:

Any analysis of whether a particular claim is supported by the disclosure in an application requires a determination of whether that disclosure, when filed, contained sufficient information regarding the subject matter of the claims as to enable one skilled in the pertinent art to make and use the claimed invention. The standard for determining whether the specification meets the enablement requirement was cast in the Supreme Court decision of Mineral Separation v. Hyde, 242 U.S. 261, 270 (1916) which postured the question: is the experimentation needed to practice the invention undue or unreasonable? That standard is still the one to be applied. In re Wands, 858 F.2d 731, 737, 8 USPQ2d 1400, 1404 (Fed. Cir. 1988).[6]M.P.E.P. § 2164.01.

Additionally, “[t]he test of enablement is not whether any experimentation is necessary, but whether, if experimentation is necessary, it is undue. In re Angstadt, 537 F.2d 498, 504, 190 USPQ 214, 219 (CCPA 1976).”[7]M.P.E.P. § 2164.01.

Determining whether experimentation is undue is a balancing test.  The M.P.E.P. offered some factors for the Examiner to consider when making this determination:

(A) The breadth of the claims;

(B) The nature of the invention;

(C) The state of the prior art;

(D) The level of one of ordinary skill;

(E) The level of predictability in the art;

(F) The amount of direction provided by the inventor;

(G) The existence of working examples; and

(H) The quantity of experimentation needed to make or use the invention based on the content of the disclosure.[8]M.P.E.P. § 2164.01(a).

Indeed, any enablement rejection requires the examiner to consider all of these factors. Failure to do so renders the rejection improper. To argue enablement, consider this strategy:

Once the examiner has weighed all the evidence and established a reasonable basis to question the enablement provided for the claimed invention, the burden falls on applicant to present persuasive arguments, supported by suitable proofs where necessary, that one skilled in the art would be able to make and use the claimed invention using the application as a guide. In re Brandstadter, 484 F.2d 1395, 1406-07, 179 USPQ 286, 294 (CCPA 1973). The evidence provided by applicant need not be conclusive but merely convincing to one skilled in the art.[9]M.P.E.P. § 2164.05.

Lastly, the best mode requirement requires the applicant to disclose the best way of carrying out the invention:

The best mode requirement creates a statutory bargained-for-exchange by which a patentee obtains the right to exclude others from practicing the claimed invention for a certain time period, and the public receives knowledge of the preferred embodiments for practicing the claimed invention.” Eli Lilly & Co. v. Barr Laboratories Inc., 251 F.3d 955, 963, 58 USPQ2d 1865, 1874 (Fed. Cir. 2001).

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. In re Nelson, 280 F.2d 172, 126 USPQ 242 (CCPA 1960).[10]M.P.E.P. § 2165.

An inquiry into the best mode requirement is a two prong analysis:

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. This is an objective inquiry, focusing on the scope of the claimed invention and the level of skill in the art. Eli Lilly & Co. v. Barr Laboratories Inc., 251 F.3d 955, 963, 58 USPQ2d 1865, 1874 (Fed. Cir. 2001).[11]M.P.E.P. § 2165.

As with other parts of the paragraph, there is a presumption that the best mode is satisfied unless evidence is presented to the contrary.[12]M.P.E.P. § 2165.03.   Keep in mind that in order to satisfy the first prong of the best-mode requirement test, there must be some evidence showing the inventor had either purposefully concealed, or what was disclosed was so poor it effectively results in concealment.[13]See, e.g., M.P.E.P. § 2165.04.

Part (b)

The point of the second subpart is to ensure that the boundaries of the patent are sufficiently clear.  The reason for this is that if an invention was not clear, it would essentially not aid in fostering innovation and progress.  Only when the metes and bounds of the claims are clearly disclosed can the public then be in a position to benefit from the disclosure and aid in fostering innovation.[14]See, e.g., M.P.E.P. § 2173.  

This paragraph sets forth two requirements to be met:

(A) the claims must set forth the subject matter that applicants regard as their invention; and

(B) the claims must particularly point out and distinctly define the metes and bounds of the subject matter that will be protected by the patent grant.[15]M.P.E.P. § 2171.

The first requirement is subjective in nature as it is based on something the applicant views.  The second requirement is objective in that it assesses whether the claims are definite (e.g. clear in scope, etc.).[16]See M.P.E.P. § 2171.

One of the clear teachings from this paragraph is that applicants are their own lexicographers.  They can define claims in any manner as long as such meaning is clearly defined in the Specification.

The test for definiteness is as follows:

The essential inquiry pertaining to this requirement is whether the claims set out and circumscribe a particular subject matter with a reasonable degree of clarity and particularity. Definiteness of claim language must be analyzed, not in a vacuum, but in light of:

(A) The content of the particular application disclosure;

(B) The teachings of the prior art; and

(C) The claim interpretation that would be given by one possessing the ordinary level of skill in the pertinent art at the time the invention was made.[17]M.P.E.P. § 2173.02.

Additionally, “[s]ome latitude in the manner of expression and the aptness of terms should be permitted even though the claim language is not as precise as the examiner might desire.”[18]M.P.E.P. § 2173.02.

In responding to a rejection under this paragraph, the M.P.E.P. gives some guidance:

the examiner should provide enough information in the Office action to permit applicant to make a meaningful response, as the indefiniteness rejection requires the applicant to explain or provide evidence as to why the claim language is not indefinite or amend the claim. For example, the examiner should point out the specific term or phrase that is indefinite, explain in detail why such term or phrase renders the metes and bounds of the claim scope unclear and, whenever practicable, indicate how the indefiniteness issues may be resolved to overcome the rejection.[19]M.P.E.P. § 2173.02.

As indicated, this rejection can be overcome by following the test as outlined above, as well as indicating why the term is not indefinite.  Additionally, it may be appropriate to compare the definition in the Specification with a dictionary or other reliable source.[20]See, e.g., 2173.05(a)(III).

As a last matter, recognize that in analyzing 112 second paragraph, such an analysis may invoke an analysis of the sixth paragraph as well (e.g. determine whether there is proper support for “means” or “function,” etc.).[21]See, e.g., 2173.01(II).

Part (d)

The fourth subpart requires correct dependency.  This is usually a straightforward matter to deal with:

Where a claim in dependent form is not considered to be a proper dependent claim under 37 CFR 1.75(c), the examiner should object to such claim under 37 CFR 1.75(c) and require cancellation of such improper dependent claim or rewriting of such improper dependent claim in independent form. See Ex parte Porter, 25 USPQ2d 1144, 1147 (Bd. of Pat. App. & Inter. 1992) (A claim determined to be an improper dependent claim should be treated as a formal matter, in that the claim should be objected to and applicant should be required to cancel the claim (or replace the improper dependent claim with an independent claim) rather than treated by a rejection of the claim under 35 U.S.C. 112, fourth paragraph.). The applicant may thereupon amend the claims to place them in proper dependent form, or may redraft them as independent claims, upon payment of any necessary additional fee.[22]M.P.E.P. § 608.01(n)(II).

More likely than not, such a rejection is easily overcome by amending the claims as appropriate.  In like manner, paragraphs 3 and 5 are somewhat related to paragraph 4 in that it relates to the form (e.g. independent v dependent, etc.) and structure (e.g. base of stemming, dependency, etc.) of the claims.


1 35 U.S.C. § 112.
2 M.P.E.P. § 2163(I).
3 M.P.E.P. § 2163(I).
4 See e.g., In re Wertheim, 541 F.2d 257, 262 (CCPA 1976).
5 See, e.g., In re Marzocchi, 439 F.2d 220, 224 (CCPA 1971).
6 M.P.E.P. § 2164.01.
7 M.P.E.P. § 2164.01.
8 M.P.E.P. § 2164.01(a).
9 M.P.E.P. § 2164.05.
10 M.P.E.P. § 2165.
11 M.P.E.P. § 2165.
12 M.P.E.P. § 2165.03.
13 See, e.g., M.P.E.P. § 2165.04.
14 See, e.g., M.P.E.P. § 2173.
15 M.P.E.P. § 2171.
16 See M.P.E.P. § 2171.
17 M.P.E.P. § 2173.02.
18 M.P.E.P. § 2173.02.
19 M.P.E.P. § 2173.02.
20 See, e.g., 2173.05(a)(III).
21 See, e.g., 2173.01(II).
22 M.P.E.P. § 608.01(n)(II).