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2173    Claims Must Particularly Point Out and Distinctly Claim the Invention [R-11.2013]

Optimizing patent quality by providing clear notice to the public of the boundaries of the inventive subject matter protected by a patent grant fosters innovation and competitiveness. Accordingly, providing high quality patents is one of the agency’s guiding principles. The Office recognizes that issuing patents with clear and definite claim language is a key component to enhancing the quality of patents and raising confidence in the patent process.

35 U.S.C. 112(b) or pre-AIA 35 U.S.C. 112, second paragraph requires that a patent application specification shall conclude with one or more claims particularly pointing out and distinctly claiming the subject matter which the applicant regards as his or her invention. In patent examining parlance, the claim language must be “definite” to comply with35 U.S.C. 112(b) or pre-AIA 35 U.S.C. 112, second paragraph. Conversely, a claim that does not comply with this requirement of 35 U.S.C. 112(b) or pre-AIA 35 U.S.C. 112, second paragraph is “indefinite.”

The primary purpose of this requirement of definiteness of claim language is to ensure that the scope of the claims is clear so the public is informed of the boundaries of what constitutes infringement of the patent. A secondary purpose is to provide a clear measure of what applicants regard as the invention so that it can be determined whether the claimed invention meets all the criteria for patentability and whether the specification meets the criteria of 35 U.S.C. 112(a) or pre-AIA 35 U.S.C. 112, first paragraph with respect to the claimed invention.

It is of utmost importance that patents issue with definite claims that clearly and precisely inform persons skilled in the art of the boundaries of protected subject matter. Therefore, claims that do not meet this standard must be rejected under 35 U.S.C. 112(b) or pre-AIA 35 U.S.C. 112, second paragraph as indefinite. Such a rejection requires that the applicant respond by explaining why the language is definite or by amending the claim, thus making the record clear regarding the claim boundaries prior to issuance. As an indefiniteness rejection requires the applicant to respond by explaining why the language is definite or by amending the claim, such rejections must clearly identify the language that causes the claim to be indefinite and thoroughly explain the reasoning for the rejection.

2173.01   Interpreting the Claims [R-11.2013]

[Editor Note: This MPEP section is applicable to applications subject to the first inventor to file (FITF) provisions of the AIA except that the relevant date is the "effective filing date" of the claimed invention instead of the "time of the invention," which is only applicable to applications subject to pre-AIA 35 U.S.C. 102. See 35 U.S.C. 100 (note) and MPEP § 2150 et seq.]

A fundamental principle contained in 35 U.S.C. 112(b) or pre-AIA 35 U.S.C. 112, second paragraph is that applicants are their own lexicographers. They can define in the claims what they regard as their invention essentially in whatever terms they choose so long as any special meaning assigned to a term is clearly set forth in the specification. See MPEP § 2111.01. Applicant may use functional language, alternative expressions, negative limitations, or any style of expression or format of claim which makes clear the boundaries of the subject matter for which protection is sought. As noted by the court in In re Swinehart, 439 F.2d 210, 160 USPQ 226 (CCPA 1971), a claim may not be rejected solely because of the type of language used to define the subject matter for which patent protection is sought.

I.   BROADEST REASONABLE INTERPRETATION

The first step to examining a claim to determine if the language is definite is to fully understand the subject matter of the invention disclosed in the application and to ascertain the boundaries of that subject matter encompassed by the claim. During examination, a claim must be given its broadest reasonable interpretation consistent with the specification as it would be interpreted by one of ordinary skill in the art. Because the applicant has the opportunity to amend claims during prosecution, giving a claim its broadest reasonable interpretation will reduce the possibility that the claim, once issued, will be interpreted more broadly than is justified. In re Yamamoto, 740 F.2d 1569, 1571 (Fed. Cir. 1984); In re Zletz, 893 F.2d 319, 321, 13 USPQ2d 1320, 1322 (Fed. Cir. 1989) (“During patent examination the pending claims must be interpreted as broadly as their terms reasonably allow.”). The focus of the inquiry regarding the meaning of a claim should be what would be reasonable from the perspective of one of ordinary skill in the art. In re Suitco Surface, Inc., 603 F.3d 1255, 1260, 94 USPQ2D 1640, 1644 (Fed. Cir. 2010); In re Buszard, 504 F.3d 1364, 84 USPQ2d 1749 (Fed. Cir. 2007). In Buszard, the claim was directed to a flame retardant composition comprising a flexible polyurethane foam reaction mixture. Buszard, 504 F.3d at 1365, 84 USPQ2d at 1749. The Federal Circuit found that the Board’s interpretation that equated a “flexible” foam with a crushed “rigid” foam was not reasonable. Id., at 1367, 84 USPQ2d at 1751. Persuasive argument was presented that persons experienced in the field of polyurethane foams know that a flexible mixture is different than a rigid foam mixture. Id., 504 F.3d at 1366, 84 USPQ2d at 1751. See MPEP § 2111 for a full discussion of broadest reasonable interpretation.

Under a broadest reasonable interpretation, words of the claim must be given their plain meaning, unless such meaning is inconsistent with the specification. The plain meaning of a term means the ordinary and customary meaning given to the term by those of ordinary skill in the art at the time of the invention. The ordinary and customary meaning of a term may be evidenced by a variety of sources, including the words of the claims themselves, the specification, drawings, and prior art. However, the best source for determining the meaning of a claim term is the specification - the greatest clarity is obtained when the specification serves as a glossary for the claim terms. The presumption that a term is given its ordinary and customary meaning may be rebutted by the applicant by clearly setting forth a different definition of the term in the specification. In re Morris, 127 F.3d 1048, 1054, 44 USPQ2d 1023, 1028 (Fed. Cir. 1997) (the USPTO looks to the ordinary use of the claim terms taking into account definitions or other “enlightenment” contained in the written description); But c.f. In re Am. Acad. of Sci. Tech. Ctr., 367 F.3d 1359, 1369, 70 USPQ2d 1827, 1834 (Fed. Cir. 2004) (“We have cautioned against reading limitations into a claim from the preferred embodiment described in the specification, even if it is the only embodiment described, absent clear disclaimer in the specification.”). When the specification sets a clear path to the claim language, the scope of the claims is more easily determined and the public notice function of the claims is best served. See MPEP § 2111.01 for a full discussion of the plain meaning of claim language.

II.   DETERMINE WHETHER OR NOT EACH CLAIM LIMITATION INVOKES 35 U.S.C. 112(f) or Pre-AIA 35 U.S.C. 112, sixth paragraph

As part of the claim interpretation analysis, examiners should determine whether each limitation invokes 35 U.S.C. 112(f) or pre-AIA 35 U.S.C. 112, sixth paragraph or not. If the claim limitation invokes 35 U.S.C. 112(f) or pre-AIA 35 U.S.C. 112, sixth paragraph, the claim limitation must “be construed to cover the corresponding structure, material, or acts described in the specification and equivalents thereof.” 35 U.S.C. 112(f) and pre-AIA 35 U.S.C. 112, sixth paragraph; see also In re Donaldson Co., 16 F.3d 1189, 1193 (Fed. Cir. 1994) (en banc) (“[W]e hold that paragraph six applies regardless of the context in which the interpretation of means-plus-function language arises, i.e., whether as part of a patentability determination in the PTO or as part of a validity or infringement determination in a court.”). See MPEP § 2181, subsection I. for more information regarding the determination of whether a limitation invokes 35 U.S.C. 112(f) or pre-AIA 35 U.S.C. 112, sixth paragraph, and means- (or step-) plus- function claim limitations.

2173.02   Determining Whether Claim Language is Definite [R-11.2013]

[Editor Note: This MPEP section is applicable to applications subject to the first inventor to file (FITF) provisions of the AIA except that the relevant date is the "effective filing date" of the claimed invention instead of the "time the invention was made," which is only applicable to applications subject to pre-AIA 35 U.S.C. 102. See 35 U.S.C. 100 (note) and MPEP § 2150 et seq.]

During prosecution, applicant has an opportunity and a duty to amend ambiguous claims to clearly and precisely define the metes and bounds of the claimed invention. The claim places the public on notice of the scope of the patentee’s right to exclude. See, e.g., Johnson & Johnston Assoc. Inc. v. R.E. Serv. Co., 285 F.3d 1046, 1052, 62 USPQ2d 1225, 1228 (Fed. Cir. 2002) (en banc). As the Federal Circuit stated in Halliburton Energy Servs., Inc. v. M-I LLC, 514 F.3d 1244, 1255, 85 USPQ2d 1654, 1663 (Fed. Cir. 2008):

We note that the patent drafter is in the best position to resolve the ambiguity in the patent claims, and it is highly desirable that patent examiners demand that applicants do so in appropriate circumstances so that the patent can be amended during prosecution rather than attempting to resolve the ambiguity in litigation.

A decision on whether a claim is indefinite under 35 U.S.C. 112(b) or pre-AIA 35 U.S.C. 112, second paragraph requires a determination of whether those skilled in the art would understand what is claimed when the claim is read in light of the specification. Power-One, Inc. v. Artesyn Techs., Inc., 599 F.3d 1343, 1350, 94 USPQ2d 1241, 1245 (Fed. Cir. 2010); Orthokinetics, Inc. v. Safety Travel Chairs, Inc., 806 F.2d 1565, 1 USPQ2d 1081 (Fed. Cir. 1986). In Orthokinetics, a claim directed to a wheel chair included the phrase “so dimensioned as to be insertable through the space between the doorframe of an automobile and one of the seats thereof.” 806 F.2d at 1568, 1 USPQ2d at 1082. The court found the phrase to be as accurate as the subject matter permits, since automobiles are of various sizes. Id., at 1576, 1 USPQ2d at 1088. “As long as those of ordinary skill in the art realized the dimensions could be easily obtained, § 112, 2d para. requires nothing more.” Id. Claim terms are typically given their ordinary and customary meaning as understood by one of ordinary skill in the pertinent art, and the generally understood meaning of particular terms may vary from art to art. Therefore, it is important to analyze claim terms in view of the application’s specification from the perspective of those skilled in the relevant art since a particular term used in one patent or application may not have the same meaning when used in a different application. Medrad, Inc. v. MRI Devices Corp., 401 F.3d 1313, 1318, 74 USPQ2d 1184, 1188 (Fed. Cir. 2005).

I.   CLAIMS UNDER EXAMINATION ARE EVALUATED WITH A DIFFERENT STANDARD THAN PATENTED CLAIMS TO DETERMINE WHETHER THE LANGUAGE IS DEFINITE

Patented claims enjoy a presumption of validity and are not given the broadest reasonable interpretation during court proceedings involving infringement and validity, and can be interpreted based on a fully developed prosecution record. Accordingly, when possible, courts construe patented claims in favor of finding a valid interpretation. A court will not find a patented claim indefinite unless it is “insolubly ambiguous.” See, e.g., Exxon Research and Eng’g Co. v. United States, 265 F.3d 1371, 1375, 60 USPQ2d 1272, 1276 (Fed. Cir. 2001); see also Metabolite Labs., Inc. v. Lab. Corp. of Am. Holdings, 370 F.3d 1354, 1366, 71 USPQ2d 1081, 1089 (Fed. Cir. 2004) (“The requirement to ‘distinctly’ claim means that the claim must have a meaning discernible to one of ordinary skill in the art when construed according to correct principles….Only when a claim remains insolubly ambiguous without a discernible meaning after all reasonable attempts at construction must a court declare it indefinite.”). In other words, the validity of a claim will be preserved if some meaning can be gleaned from the language.

In contrast, no presumption of validity attaches before the issuance of a patent. The Office is not required or even permitted to interpret claims when examining patent applications in the same manner as the courts, which, post-issuance, operate under the presumption of validity. In re Morris, 127 F.3d 1048, 1054, 44 USPQ2d 1023, 1028 (Fed. Cir. 1997); In re Zletz, 893 F.2d 319, 321-22 (Fed. Cir. 1989). The Office must construe claims in the broadest reasonable manner during prosecution in an effort to establish a clear record of what applicant intends to claim. In deciding whether a pending claim particularly points out and distinctly claims the subject matter, a lower threshold of ambiguity is applied during prosecution. Ex parte Miyazaki, 89 USPQ2d 1207, 1212 (Bd. Pat. App. & Int. 2008) (precedential); In re Am. Acad. of Sci. Tech Center, 367 F.3d 1359, 1369, 70 USPQ2d 1827, 1834 (Fed. Cir. 2004) (“However, the Board is required to use a different standard for construing claims than that used by district courts.”). The lower threshold is applied because the patent record is in development and not fixed. As such, applicant has the ability to provide explanation and/or amend the claims to ensure that the meaning of the language is clear and definite prior to issuance. Burlington Indus. Inc. v. Quigg, 822 F.2d 1581, 1583, 3 USPQ2d 1436, 1438 (Fed. Cir. 1987) (“Issues of judicial claim construction such as arise after patent issuance, for example during infringement litigation, have no place in prosecution of pending claims before the PTO, when any ambiguity or excessive breadth may be corrected by merely changing the claim.”).

During examination, after applying the broadest reasonable interpretation to the claim, if the metes and bounds of the claimed invention are not clear, the claim is indefinite and should be rejected. Zletz, 893 F.2d at 322, 13 USPQ2d at 1322. For example, if the language of a claim, given its broadest reasonable interpretation, is such that a person of ordinary skill in the relevant art would read it with more than one reasonable interpretation, then a rejection under 35 U.S.C. 112(b) or pre-AIA 35 U.S.C. 112, second paragraph is appropriate. Examiners, however, are cautioned against confusing claim breadth with claim indefiniteness. A broad claim is not indefinite merely because it encompasses a wide scope of subject matter provided the scope is clearly defined. Instead, a claim is indefinite when the boundaries of the protected subject matter are not clearly delineated and the scope is unclear. For example, a genus claim that covers multiple species is broad, but is not indefinite because of its breadth, which is otherwise clear. But a genus claim that could be interpreted in such a way that it is not clear which species are covered would be indefinite (e.g., because there is more than one reasonable interpretation of what species are included in the claim). See MPEP § 2173.05(h), subsection I., for more information regarding the determination of whether a Markush claim satisfies the requirements of 35 U.S.C. 112(b) or pre-AIA 35 U.S.C. 112, second paragraph.

II.   THRESHOLD REQUIREMENTS OF CLARITY AND PRECISION

The examiner’s focus during examination of claims for compliance with the requirement for definiteness of 35 U.S.C. 112(b) or pre-AIA 35 U.S.C. 112, second paragraph, is whether the claim meets the threshold requirements of clarity and precision set forth in the statute, not whether more suitable language or modes of expression are available. When the examiner is satisfied that patentable subject matter is disclosed, and it is apparent to the examiner that the claims are directed to such patentable subject matter, he or she should allow claims which define the patentable subject matter with the required degree of particularity and distinctness. Some latitude in the manner of expression and the aptness of terms should be permitted so long as 35 U.S.C. 112(b) or pre-AIA 35 U.S.C. 112, second paragraph, is satisfied. Examiners are encouraged to suggest claim language to applicants to improve the clarity or precision of the language used, but should not insist on their own preferences if other modes of expression selected by applicants satisfy the statutory requirement.

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.

In reviewing a claim for compliance with 35 U.S.C. 112(b) or pre-AIA 35 U.S.C. 112, second paragraph, the examiner must consider the claim as a whole to determine whether the claim apprises one of ordinary skill in the art of its scope and, therefore, serves the notice function required by 35 U.S.C. 112(b) or pre-AIA 35 U.S.C. 112, second paragraph, by providing clear warning to others as to what constitutes infringement of the patent. See, e.g., Solomon v. Kimberly-Clark Corp., 216 F.3d 1372, 1379, 55 USPQ2d 1279, 1283 (Fed. Cir. 2000). See also In re Larsen, No. 01-1092 (Fed. Cir. May 9, 2001) (unpublished) (The preamble of the Larsen claim recited only a hanger and a loop but the body of the claim positively recited a linear member. The court observed that the totality of all the limitations of the claim and their interaction with each other must be considered to ascertain the inventor’s contribution to the art. Upon review of the claim in its entirety, the court concluded that the claim at issue apprises one of ordinary skill in the art of its scope and, therefore, serves the notice function required by 35 U.S.C. 112.).

A claim term that is not used or defined in the specification may not be indefinite if the meaning of the claim term is discernible. Bancorp Services, L.L.C. v. Hartford Life Ins. Co., 359 F.3d 1367, 1372, 69 USPQ2d 1996, 1999-2000 (Fed. Cir. 2004) (holding that the disputed claim term “surrender value protected investment credits” which was not defined or used in the specification was discernible and hence not indefinite because “the components of the term have well recognized meanings, which allow the reader to infer the meaning of the entire phrase with reasonable confidence”).

If the language of the claim is such that a person of ordinary skill in the art could not interpret the metes and bounds of the claim so as to understand how to avoid infringement, a rejection of the claim under 35 U.S.C. 112(b) or pre-AIA 35 U.S.C. 112, second paragraph, is appropriate. See Morton Int’l, Inc. v. Cardinal Chem. Co., 5 F.3d 1464, 1470, 28 USPQ2d 1190, 1195 (Fed. Cir. 1993). However, if the language used by applicant satisfies the statutory requirements of 35 U.S.C. 112(b) or pre-AIA 35 U.S.C. 112, second paragraph, the claim must not be rejected under 35 U.S.C. 112(b) or pre-AIA 35 U.S.C. 112, second paragraph.

Examiners should note that Office policy is not to employ per se rules to make technical rejections. Examples of claim language which have been held to be indefinite set forth in MPEP § 2173.05(d) are fact specific and should not be applied as per se rules. The test for definiteness under 35 U.S.C. 112(b) or pre-AIA 35 U.S.C. 112, second paragraph, is whether “those skilled in the art would understand what is claimed when the claim is read in light of the specification.” Orthokinetics, Inc. v. Safety Travel Chairs, Inc., 806 F.2d 1565, 1576, 1 USPQ2d 1081, 1088 (Fed. Cir. 1986). If one skilled in the art is able to ascertain in the example above, the meaning of the terms “suitable liquid” and “solids of a filtering agent” in light of the specification, 35 U.S.C. 112(b) or pre-AIA 35 U.S.C. 112, second paragraph, is satisfied. If upon review of the claim as a whole in light of the specification, the examiner determines that a rejection under 35 U.S.C. 112(b) or pre-AIA 35 U.S.C. 112, second paragraph, is not appropriate in the above-noted example, but is of the opinion that the clarity and the precision of the language can be improved by the deletion of the phrase “such as” in the claim, the examiner may make such a suggestion to the applicant. If applicant does not accept the examiner’s suggestion, the examiner should not pursue the issue.

III.   RESOLVING INDEFINITE CLAIM LANGUAGE

A.   Examiner Must Establish a Clear Record

Examiners are urged to carefully carry out their responsibilities to see that the application file contains a complete and accurate picture of the Office’s consideration of the patentability of an application. See MPEP § 1302.14, subsection I. In order to provide a complete application file history and to enhance the clarity of the prosecution history record, an examiner should provide clear explanations of all actions taken during prosecution of the application. See MPEP § 707.07(f). Thus, when a rejection under 35 U.S.C. 112(b) or pre-AIA 35 U.S.C. 112, second paragraph, is appropriate based on the examiner’s determination that a claim term or phrase is indefinite, the examiner should clearly communicate in an Office action any findings and reasons which support the rejection and avoid a mere conclusion that the claim term or phrase is indefinite. See MPEP § 706.03 and MPEP § 707.07(g).

MPEP § 2173.05 provides numerous examples of rationales that may support a rejection under 35 U.S.C. 112(b) or pre-AIA 35 U.S.C. 112, second paragraph, such as functional claim limitations, relative terminology/terms of degree, lack of antecedent basis, etc. Only by providing a complete explanation in the Office action as to the basis for determining why a particular term or phrase used in the claim is “vague and indefinite” will the examiner enhance the clarity of the prosecution history record.

B.   An Office Action Should Provide a Sufficient Explanation

The Office action must set forth the specific term or phrase that is indefinite and why the metes and bounds are unclear. Since a rejection requires the applicant to respond by explaining why claim language is definite or by amending the claim, the Office action should provide enough information for the applicant to prepare a meaningful response. “Because claims delineate the patentee’s right to exclude, the patent statute requires that the scope of the claims be sufficiently definite to inform the public of the bounds of the protected invention, i.e., what subject matter is covered by the exclusive rights of the patent.” Halliburton Energy Servs., Inc. v. M-I LLC, 514 F.3d 1244, 1249, 85 USPQ2d 1654, 1658 (Fed. Cir. 2008). Thus, claims are given their broadest reasonable interpretation during prosecution “to facilitate sharpening and clarifying the claims at the application stage” when claims are readily changed. In re Buszard, 504 F.3d 1364, 1366 (Fed. Cir. 2007); see also In re Yamamoto, 740 F.2d 1569, 1571 (Fed. Cir. 1984); In re Zletz, 893 F.2d 319, 322, 13 USPQ2d 1320, 1322 (Fed. Cir. 1989).

To comply with 35 U.S.C. 112(b) or pre-AIA 35 U.S.C. 112, second paragraph, applicants are required to make the terms that are used to define the invention clear and precise, so that the metes and bounds of the subject matter that will be protected by the patent grant can be ascertained. See MPEP § 2173.05(a), subsection I. It is important that a person of ordinary skill in the art be able to interpret the metes and bounds of the claims so as to understand how to avoid infringement of the patent that ultimately issues from the application being examined. See MPEP § 2173.02, subsection II (citing Morton Int ’l, Inc. v. Cardinal Chem. Co., 5 F.3d 1464, 1470 (Fed. Cir. 1993)); see also Halliburton Energy Servs., 514 F.3d at 1249, 85 USPQ2d at 1658 (“Otherwise, competitors cannot avoid infringement, defeating the public notice function of patent claims.”). Examiners should bear in mind that “[a]n essential purpose of patent examination is to fashion claims that are precise, clear, correct, and unambiguous. Only in this way can uncertainties of claim scope be removed, as much as possible, during the administrative process.” Zletz, 893 F.2d at 322, 13 USPQ2d at 1322.

Accordingly, when rejecting a claim as indefinite under 35 U.S.C. 112(b) or pre-AIA 35 U.S.C. 112, second paragraph, 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. See MPEP § 707.07(d).

The focus during the examination of claims for compliance with the requirement for definiteness under 35 U.S.C. 112(b) or pre-AIA 35 U.S.C. 112, second paragraph, is whether the claim meets the threshold requirements of clarity and precision, not whether more suitable language or modes of expression are available. See MPEP § 2173.02, subsection II. If the language used by applicant satisfies the statutory requirement of 35 U.S.C. 112(b) or pre-AIA 35 U.S.C. 112, second paragraph, but the examiner merely wants the applicant to improve the clarity or precision of the language used, the examiner should suggest improved claim language to the applicant and not make a rejection under 35 U.S.C. 112(b) or pre-AIA 35 U.S.C. 112, second paragraph. See, e.g., In re Skvorecz, 580 F.3d 1262, 1268-69, 92 USPQ2d 1020, 1025 (Fed. Cir. 2009). Furthermore, when the examiner determines that more information is necessary to ascertain the meaning of a claim term, a requirement for information under 37 CFR 1.105 is appropriate. See MPEP § 704.10 regarding requirements for information.

It is highly desirable to have applicants resolve ambiguity by amending the claims during prosecution of the application rather than attempting to resolve the ambiguity in subsequent litigation of the issued patent. Halliburton Energy Servs., 514 F.3d at 1255. Likewise, if the applicant traverses a rejection under 35 U.S.C. 112(b) or pre-AIA 35 U.S.C. 112, second paragraph, with or without the submission of an amendment, and the examiner considers applicant’s arguments to be persuasive, the examiner should indicate in the next Office communication that the previous rejection under 35 U.S.C. 112(b) or pre-AIA 35 U.S.C. 112, second paragraph, has been withdrawn and provide an explanation as to what prompted the change in the examiner’s position (e.g., by making specific reference to portions of applicant’s remarks).

By providing an explanation as to the action taken, the examiner will enhance the clarity of the prosecution history record. As noted by the Supreme Court in Festo Corp. v. Shoketsu Kinzoku Kogyo Kabushiki Co., 535 U.S. 722, 122 S.Ct. 1831, 1838, 62 USPQ2d 1705, 1710 (2002), a clear and complete prosecution file record is important in that “[p]rosecution history estoppel requires that the claims of a patent be interpreted in light of the proceedings in the PTO during the application process.” In Festo, the court held that “a narrowing amendment made to satisfy any requirement of the Patent Act may give rise to an estoppel.” With respect to amendments made to comply with the requirements of 35 U.S.C. 112, the court stated that “[i]f a § 112 amendment is truly cosmetic, then it would not narrow the patent’s scope or raise an estoppel. On the other hand, if a § 112 amendment is necessary and narrows the patent’s scope—even if only for the purpose of better description—estoppel may apply.” Id. at 1840, 62 USPQ2d at 1712. The court further stated that “when the court is unable to determine the purpose underlying a narrowing amendment—and hence a rationale for limiting the estoppel to the surrender of particular equivalents—the court should presume that the patentee surrendered all subject matter between the broader and the narrower language…the patentee should bear the burden of showing that the amendment does not surrender the particular equivalent in question.” Id. at 1842, 62 USPQ2d at 1713. Thus, whenever possible, the examiner should make the record clear by providing explicit reasoning for making or withdrawing any rejection related to 35 U.S.C. 112(b) or pre-AIA 35 U.S.C. 112, second paragraph.

C.   Provide Claim Interpretation in Reasons for Allowance When Record is Unclear

Pursuant to 37 CFR 1.104(e), if the examiner believes that the record of the prosecution as a whole does not make clear his or her reasons for allowing a claim or claims, the examiner may set forth such reasoning in reasons for allowance. Further, prior to allowance, the examiner may also specify allowable subject matter and provide reasons for indicating such allowable subject matter in an Office communication. See MPEP § 1302.14, subsection I. One of the primary purposes of 37 CFR 1.104(e) is to improve the quality and reliability of issued patents by providing a complete file history which should clearly reflect the reasons why the application was allowed. Such information facilitates evaluation of the scope and strength of a patent by the patentee and the public and may help avoid or simplify subsequent litigation of an issued patent. See MPEP § 1302.14, subsection I. In meeting the need for the application file history to speak for itself, it is incumbent upon the examiner in exercising his or her responsibility to the public to see that the file history is complete. See MPEP § 1302.14, subsection I.

For example, when allowing a claim based on a claim interpretation which might not be readily apparent from the record of the prosecution as a whole, the examiner should set forth in reasons for allowance the claim interpretation that he or she applied in determining that the claim is allowable over the prior art. See MPEP § 1302.14, subsection II.G. This is especially the case where the application is allowed after an interview. The examiner should ensure, however, that statements of reasons for allowance do not place unwarranted interpretations, whether broad or narrow, upon the claims. See MPEP § 1302.14, subsection I.

D.   Open Lines of Communication with the Applicant – When Indefiniteness Is the Only Issue, Attempt Resolution through an Interview before Resorting to a Rejection

Examiners are reminded that interviews can be an effective examination tool and are encouraged to initiate an interview with the applicant or applicant’s representative at any point during the pendency of an application, if the interview can help further prosecution, shorten pendency, or provide a benefit to the examiner or applicant.. Issues of claim interpretation and clarity of scope may lend themselves to resolution through an examiner interview. For example, the examiner may initiate an interview to discuss, among other issues, the broadest reasonable interpretation of a claim, the meaning of a particular claim limitation, and the scope and clarity of preamble language, functional language, intended use language, and means-plus-function limitations, etc.

An interview can serve to develop and clarify such issues and lead to a mutual understanding between the examiner and the applicant, potentially eliminating the need for the examiner to resort to making a rejection under 35 U.S.C. 112(b) or pre-AIA 35 U.S.C. 112, second paragraph. The examiner is reminded that the substance of any interview, whether in person, by video conference, or by telephone must be made of record in the application, whether or not an agreement was reached at the interview. See MPEP § 713.04; see also 37 CFR 1.2 (“The action of the Patent and Trademark Office will be based exclusively on the written record in the Office. No attention will be paid to any alleged oral promise, stipulation, or understanding in relation to which there is disagreement or doubt.”). Examples of 35 U.S.C. 112 issues that should be made of record after the interview include: why the discussed claim term is or is not sufficiently clear; why the discussed claim term is or is not inconsistent with the specification; why the discussed claim term does or does not invoke 35 U.S.C. 112(f) or pre-AIA 35 U.S.C. 112, sixth paragraph (and if it does, the identification of corresponding structure in the specification for a 35 U.S.C. 112(f) or pre-AIA 35 U.S.C. 112, sixth paragraph limitation); and any claim amendments discussed that would resolve identified ambiguities.

2173.03   Correspondence Between Specification and Claims [R-11.2013]

The specification should ideally serve as a glossary to the claim terms so that the examiner and the public can clearly ascertain the meaning of the claim terms. Correspondence between the specification and claims is required by 37 CFR 1.75(d)(1), which provides that claim terms must find clear support or antecedent basis in the specification so that the meaning of the terms may be ascertainable by reference to the specification. To meet the definiteness requirement under 35 U.S.C. 112(b) or pre-AIA 35 U.S.C. 112, second paragraph, the exact claim terms are not required to be used in the specification as long as the specification provides the needed guidance on the meaning of the terms (e.g., by using clearly equivalent terms) so that the meaning of the terms is readily discernable to a person of ordinary skill in the art. See, e.g., Bancorp Servs., L.L.C. v. Hartford Life Ins. Co., 359 F.3d 1367, 1373 (Fed. Cir. 2004). Nevertheless, glossaries of terms used in the claims are a helpful device for ensuring adequate definition of terms used in claims. Express definitions of claim terms can eliminate the need for any “time-consuming and difficult inquiry into indefiniteness.” Id. Therefore, applicants are encouraged to use glossaries as a best practice in patent application preparation. If the specification does not provide the needed support or antecedent basis for the claim terms, the specification should be objected to under 37 CFR 1.75(d)(1). See MPEP § 608.01(o) and MPEP § 2181, subsection IV. Applicant will be required to make appropriate amendment to the description to provide clear support or antecedent basis for the claim terms provided no new matter is introduced, or amend the claim.

A claim, although clear on its face, may also be indefinite when a conflict or inconsistency between the claimed subject matter and the specification disclosure renders the scope of the claim uncertain as inconsistency with the specification disclosure or prior art teachings may make an otherwise definite claim take on an unreasonable degree of uncertainty. In re Moore, 439 F.2d 1232, 1235-36 (CCPA 1971); In re Cohn, 438 F.2d 989, 169 USPQ 95 (CCPA 1971); In reHammack, 427 F.2d 1378, 166 USPQ 204 (CCPA 1970). For example, a claim with a limitation of “the clamp means including a clamp body and first and second clamping members, the clamping members being supported by the clamp body” was determined to be indefinite because the terms “first and second clamping members” and “clamp body” were found to be vague in light of the specification which showed no “clamp member” structure being “supported by the clamp body.” In re Anderson, 1997 U.S. App. Lexis 167 (Fed. Cir. Jan. 6, 1997) (unpublished). In Cohn, a claim was directed to a process of treating an aluminum surface with an alkali silicate solution and included a further limitation that the surface has an “opaque” appearance. Id. The specification, meanwhile, associated the use of an alkali silicate with a glazed or porcelain-like finish, which the specification distinguished from an opaque finish. Cohn, 438 F.2d at 993. Noting that no claim may be read apart from and independent of the supporting disclosure on which it is based, the court found that the claim was internally inconsistent based on the description, definitions and examples set forth in the specification relating to the appearance of the surface after treatment, and therefore indefinite. Id.

2173.04   Breadth Is Not Indefiniteness [R-11.2013]

Breadth of a claim is not to be equated with indefiniteness. In reMiller, 441 F.2d 689, 169 USPQ 597 (CCPA 1971). If the scope of the subject matter embraced by the claims is clear, and if applicants have not otherwise indicated that they intend the invention to be of a scope different from that defined in the claims, then the claims comply with 35 U.S.C. 112(b) or pre-AIA 35 U.S.C. 112, second paragraph. See Ultimax Cement Mfg. v. CTS Cement Mfg., 587 F.3d 1339, 1352, 92 USPQ2d 1865, 1873 (Fed. Cir. 2010) (finding that “a claim to a formula containing over 5000 possible combinations is not necessarily ambiguous if it sufficiently notifies the public of the scope of the claims."). A claim is indefinite when the boundaries of the protected subject matter are not clearly delineated and the scope is unclear. For example, a genus claim that covers multiple species is broad, but is not indefinite because of its breadth, which is otherwise clear. But a genus claim that could be interpreted in such a way that it is not clear which species are covered would be indefinite (e.g., because there is more than one reasonable interpretation of what species are included in the claim).

Undue breadth of the claim may be addressed under different statutory provisions, depending on the reasons for concluding that the claim is too broad. If the claim is too broad because it does not set forth that which applicants regard as their invention as evidenced by statements outside of the application as filed, a rejection under 35 U.S.C. 112(b) or pre-AIA 35 U.S.C. 112, second paragraph, would be appropriate. If the claim is too broad because it is not supported by the original description or by an enabling disclosure, a rejection under 35 U.S.C. 112(a) or pre-AIA 35 U.S.C. 112, first paragraph, would be appropriate. If the claim is too broad because it reads on the prior art, a rejection under either 35 U.S.C. 102 or 103 would be appropriate.

2173.05   Specific Topics Related to Issues Under 35 U.S.C. 112(b) or Pre-AIA 35 U.S.C. 112, Second Paragraph [R-11.2013]

The following sections are devoted to a discussion of specific topics where issues under 35 U.S.C. 112(b) or pre-AIA 35 U.S.C. 112, second paragraph, have been addressed. These sections are not intended to be an exhaustive list of the issues that can arise under 35 U.S.C. 112(b) or pre-AIA 35 U.S.C. 112, second paragraph, but are intended to provide guidance in areas that have been addressed with some frequency in recent examination practice. The court and Board decisions cited are representative. As with all appellate decisions, the results are largely dictated by the facts in each case. The use of the same language in a different context may justify a different result.

See MPEP § 2181 for guidance in determining whether an applicant has complied with the requirements of 35 U.S.C. 112(b) or pre-AIA 35 U.S.C. 112, second paragraph, when 35 U.S.C. 112(f) or pre-AIA 35 U.S.C. 112, sixth paragraph, is invoked.

2173.05(a)   New Terminology

I.   THE MEANING OF EVERY TERM SHOULD BE APPARENT

The meaning of every term used in a claim should be apparent from the prior art or from the specification and drawings at the time the application is filed. Applicants need not confine themselves to the terminology used in the prior art, but are required to make clear and precise the terms that are used to define the invention whereby the metes and bounds of the claimed invention can be ascertained. During patent examination, the pending claims must be given the broadest reasonable interpretation consistent with the specification. In re Morris, 127 F.3d 1048, 1054, 44 USPQ2d 1023, 1027 (Fed. Cir. 1997); In re Prater, 415 F.2d 1393, 162 USPQ 541 (CCPA 1969). See also MPEP § 2111 - § 2111.01. When the specification states the meaning that a term in the claim is intended to have, the claim is examined using that meaning, in order to achieve a complete exploration of the applicant’s invention and its relation to the prior art. In re Zletz, 893 F.2d 319, 13 USPQ2d 1320 (Fed. Cir. 1989).

II.   THE REQUIREMENT FOR CLARITY AND PRECISION MUST BE BALANCED WITH THE LIMITATIONS OF THE LANGUAGE

Courts have recognized that it is not only permissible, but often desirable, to use new terms that are frequently more precise in describing and defining the new invention. In reFisher, 427 F.2d 833, 166 USPQ 18 (CCPA 1970). Although it is difficult to compare the claimed invention with the prior art when new terms are used that do not appear in the prior art, this does not make the new terms indefinite.

New terms are often used when a new technology is in its infancy or is rapidly evolving. The requirements for clarity and precision must be balanced with the limitations of the language and the science. If the claims, read in light of the specification, reasonably apprise those skilled in the art both of the utilization and scope of the invention, and if the language is as precise as the subject matter permits, the statute (35 U.S.C. 112(b) or pre-AIA 35 U.S.C. 112, second paragraph) demands no more. Shatterproof Glass Corp. v. Libbey Owens Ford Co., 758 F.2d 613, 225 USPQ 634 (Fed. Cir. 1985) (interpretation of “freely supporting” in method claims directed to treatment of a glass sheet); Hybritech, Inc. v. Monoclonal Antibodies, Inc., 802 F.2d 1367, 231 USPQ 81 (Fed. Cir. 1986) (interpretation of a limitation specifying a numerical value for antibody affinity where the method of calculation was known in the art at the time of filing to be imprecise). This does not mean that the examiner must accept the best effort of applicant. If the language is not considered as precise as the subject matter permits, the examiner should provide reasons to support the conclusion of indefiniteness and is encouraged to suggest alternatives that would not be subject to rejection.

III.   TERMS USED CONTRARY TO THEIR ORDINARY MEANING MUST BE CLEARLY REDEFINED IN THE WRITTEN DESCRIPTION

Consistent with the well-established axiom in patent law that a patentee or applicant is free to be his or her own lexicographer, a patentee or applicant may use terms in a manner contrary to or inconsistent with one or more of their ordinary meanings if the written description clearly redefines the terms. See, e.g., Process Control Corp. v. HydReclaim Corp., 190 F.3d 1350, 1357, 52 USPQ2d 1029, 1033 (Fed. Cir. 1999) (“While we have held many times that a patentee can act as his own lexicographer to specifically define terms of a claim contrary to their ordinary meaning,” in such a situation the written description must clearly redefine a claim term “so as to put a reasonable competitor or one reasonably skilled in the art on notice that the patentee intended to so redefine that claim term.”); Hormone Research Foundation Inc.v.Genentech Inc., 904 F.2d 1558, 15 USPQ2d 1039 (Fed. Cir. 1990). Accordingly, when there is more than one meaning for a term, it is incumbent upon applicant to make clear which meaning is being relied upon to claim the invention. Until the meaning of a term or phrase used in a claim is clear, a rejection under 35 U.S.C. 112(b) or pre-AIA 35 U.S.C. 112, second paragraph is appropriate. It is appropriate to compare the meaning of terms given in technical dictionaries in order to ascertain the accepted meaning of a term in the art. In re Barr, 444 F.2d 588, 170 USPQ 330 (CCPA 1971). See also MPEP § 2111.01.

2173.05(b)   Relative Terminology

The use of relative terminology in claim language, including terms of degree, does not automatically render the claim indefinite under 35 U.S.C. 112(b) or pre-AIA 35 U.S.C. 112, second paragraph. Seattle Box Co., Inc. v. Industrial Crating & Packing, Inc., 731 F.2d 818, 221 USPQ 568 (Fed. Cir. 1984). Acceptability of the claim language depends on whether one of ordinary skill in the art would understand what is claimed, in light of the specification.

I.   TERMS OF DEGREE

When a term of degree is used in the claim, the examiner should determine whether the specification provides some standard for measuring that degree. Hearing Components, Inc. v. Shure Inc., 600 F.3d 1357, 1367, 94 USPQ2d 1385, 1391 (Fed. Cir. 2010); Enzo Biochem, Inc., v. Applera Corp., 599 F.3d 1325, 1332, 94 USPQ2d 1321, 1326 (Fed. Cir. 2010); Seattle Box Co., Inc. v. Indus. Crating & Packing, Inc., 731 F.2d 818, 826, 221 USPQ 568, 574 (Fed. Cir. 1984). If the specification does not provide some standard for measuring that degree, a determination must be made as to whether one of ordinary skill in the art could nevertheless ascertain the scope of the claim (e.g., a standard that is recognized in the art for measuring the meaning of the term of degree). The claim is not indefinite if the specification provides examples or teachings that can be used to measure a degree even without a precise numerical measurement (e.g., a figure that provides a standard for measuring the meaning of the term of degree). See, e.g., Young v. Lumenis, Inc., 492 F.3d 1336, 1346 (Fed. Cir. 2007); Exxon Research and Eng’g Co. v. United States, 265 F.3d 1371, 1381, 60 USPQ2d 1272, 1281 (Fed. Cir. 2001). During prosecution, an applicant may also overcome an indefiniteness rejection by providing evidence that the meaning of the term can be ascertained by one of ordinary skill in the art when reading the disclosure. For example, in Enzo Biochem, the applicant submitted a declaration under 37 CFR 1.132 showing examples that met the claim limitation and examples that did not. Enzo Biochem, 599 F.3d at 1335, 94 USPQ2d at 1328 (noting that applicant overcame an indefiniteness rejection over “not interfering substantially” claim language by submitting a declaration under 37 CFR 1.132 listing eight specific linkage groups that applicant declared did not substantially interfere with hybridization or detection).

Even if the specification uses the same term of degree as in the claim, a rejection is proper if the scope of the term is not understood when read in light of the specification. While, as a general proposition, broadening modifiers are standard tools in claim drafting in order to avoid reliance on the doctrine of equivalents in infringement actions, when the scope of the claim is unclear a rejection under 35 U.S.C. 112(b) or pre-AIA 35 U.S.C. 112, second paragraph, is proper. See In re Wiggins, 488 F. 2d 538, 541, 179 USPQ 421, 423 (CCPA 1973).

When relative terms are used in claims wherein the improvement over the prior art rests entirely upon size or weight of an element in a combination of elements, the adequacy of the disclosure of a standard is of greater criticality.

II.   REFERENCE TO AN OBJECT THAT IS VARIABLE MAY RENDER A CLAIM INDEFINITE

A claim may be rendered indefinite by reference to an object that is variable. See, e.g., Ex parte Miyazaki, 89 USPQ2d 1207 (Bd. Pat. App. & Int. 2008) (precedential) and Ex parte Brummer, 12 USPQ2d 1653 (Bd. Pat. App. & Inter. 1989). In Miyazaki, the Board held that claims to a large printer were not sufficiently definite because:

The language of claim 1 attempts to claim the height of the paper feeding unit in relation to a user of a specific height who is performing operations on the printer.... Claim 1 fails to specify, however, a positional relationship of the user and the printer to each other.

Miyazaki, 89 USPQ2d at 1212. In Brummer, the Board held that a limitation in a claim to a bicycle that recited “said front and rear wheels so spaced as to give a wheelbase that is between 58 percent and 75 percent of the height of the rider that the bicycle was designed for” was indefinite because the relationship of parts was not based on any known standard for sizing a bicycle to a rider, but on a rider of unspecified build. Brummer, 12 USPQ2d at 1655.

On the other hand, a claim limitation specifying that a certain part of a pediatric wheelchair be “so dimensioned as to be insertable through the space between the doorframe of an automobile and one of the seats” was held to be definite. Orthokinetics, Inc.v.Safety Travel Chairs, Inc., 806 F.2d 1565, 1 USPQ2d 1081 (Fed. Cir. 1986). The court stated that the phrase “so dimensioned” is as accurate as the subject matter permits, noting that the patent law does not require that all possible lengths corresponding to the spaces in hundreds of different automobiles be listed in the patent, let alone that they be listed in the claims.

A.   “About”

In determining the range encompassed by the term "about" , one must consider the context of the term as it is used in the specification and claims of the application. Ortho-McNeil Pharm., Inc. v. Caraco Pharm. Labs., Ltd., 476 F.3d 1321, 1326, 81 USPQ2d 1427, 1432 (Fed. Cir. 2007). InW.L. Gore & Associates, Inc.v.Garlock, Inc., 721 F.2d 1540, 220 USPQ 303 (Fed. Cir. 1983), the court held that a limitation defining the stretch rate of a plastic as “exceeding about 10% per second” is definite because infringement could clearly be assessed through the use of a stopwatch. However, in another case, the court held that claims reciting “at least about” were invalid for indefiniteness where there was close prior art and there was nothing in the specification, prosecution history, or the prior art to provide any indication as to what range of specific activity is covered by the term “about.” Amgen, Inc. v.Chugai Pharmaceutical Co., 927 F.2d 1200, 18 USPQ2d 1016 (Fed. Cir. 1991).

B.   “Essentially”

The phrase “a silicon dioxide source that is essentially free of alkali metal” was held to be definite because the specification contained guidelines and examples that were considered sufficient to enable a person of ordinary skill in the art to draw a line between unavoidable impurities in starting materials and essential ingredients. In reMarosi, 710 F.2d 799, 218 USPQ 289 (CCPA 1983). The court further observed that it would be impractical to require applicants to specify a particular number as a cutoff between their invention and the prior art.

C.   “Similar”

The term “similar” in the preamble of a claim that was directed to a nozzle “for high-pressure cleaning units or similar apparatus” was held to be indefinite since it was not clear what applicant intended to cover by the recitation “similar” apparatus. Ex parteKristensen, 10 USPQ2d 1701 (Bd. Pat. App. & Inter. 1989).

A claim in a design patent application which read: “The ornamental design for a feed bunk or similar structure as shown and described.” was held to be indefinite because it was unclear from the specification what applicant intended to cover by the recitation of “similar structure.” Ex partePappas, 23 USPQ2d 1636 (Bd. Pat. App. & Inter. 1992).

D.   “Substantially”

The term “substantially” is often used in conjunction with another term to describe a particular characteristic of the claimed invention. It is a broad term. In reNehrenberg, 280 F.2d 161, 126 USPQ 383 (CCPA 1960). The court held that the limitation “to substantially increase the efficiency of the compound as a copper extractant” was definite in view of the general guidelines contained in the specification. In reMattison, 509 F.2d 563, 184 USPQ 484 (CCPA 1975). The court held that the limitation “which produces substantially equal E and H plane illumination patterns” was definite because one of ordinary skill in the art would know what was meant by “substantially equal.” Andrew Corp.v.Gabriel Electronics, 847 F.2d 819, 6 USPQ2d 2010 (Fed. Cir. 1988).

E.   “Type”

The addition of the word “type” to an otherwise definite expression (e.g., Friedel-Crafts catalyst) extends the scope of the expression so as to render it indefinite. Ex parteCopenhaver, 109 USPQ 118 (Bd. App. 1955). Likewise, the phrase “ZSM-5-type aluminosilicate zeolites” was held to be indefinite because it was unclear what “type” was intended to convey. The interpretation was made more difficult by the fact that the zeolites defined in the dependent claims were not within the genus of the type of zeolites defined in the independent claim. Ex parteAttig, 7 USPQ2d 1092 (Bd. Pat. App. & Inter. 1986).

F.   Other Terms

The phrases “relatively shallow,” “of the order of,” “the order of about 5mm,” and “substantial portion” were held to be indefinite because the specification lacked some standard for measuring the degree intended and, therefore, properly rejected as indefinite under 35 U.S.C. 112(b) or pre-AIA 35 U.S.C. 112, second paragraph. Ex parteOetiker, 23 USPQ2d 1641 (Bd. Pat. App. & Inter. 1992).

The term “or like material” in the context of the limitation “coke, brick, or like material” was held to render the claim indefinite since it was not clear how the materials other than coke or brick had to resemble the two specified materials to satisfy the limitations of the claim. Ex parteCaldwell, 1906 C.D. 58 (Comm’r Pat. 1906).

The terms “comparable” and “superior” were held to be indefinite in the context of a limitation relating the characteristics of the claimed material to other materials - “properties that are superior to those obtained with comparable” prior art materials. Ex parteAnderson, 21 USPQ2d 1241 (Bd. Pat. App. & Inter. 1991). It was not clear from the specification which properties had to be compared and how comparable the properties would have to be to determine infringement issues. Further, there was no guidance as to the meaning of the term “superior.”

III.   SUBJECTIVE TERMS

When a subjective term is used in the claim, the examiner should determine whether the specification supplies some standard for measuring the scope of the term, similar to the analysis for a term of degree. Some objective standard must be provided in order to allow the public to determine the scope of the claim. A claim that requires the exercise of subjective judgment without restriction may render the claim indefinite. In re Musgrave, 431 F.2d 882, 893 (CCPA 1970). Claim scope cannot depend solely on the unrestrained, subjective opinion of a particular individual purported to be practicing the invention. Datamize LLC v. Plumtree Software, Inc., 417 F.3d 1342, 1350, 75 USPQ2d 1801, 1807 (Fed. Cir. 2005).

For example, in Datamize, the invention was directed to a computer interface screen with an “aesthetically pleasing look and feel.” Datamize, 417 F.3d at 1344-45. The meaning of the term “aesthetically pleasing” depended solely on the subjective opinion of the person selecting features to be included on the interface screen. Nothing in the intrinsic evidence (e.g., the specification) provided any guidance as to what design choices would result in an “aesthetically pleasing” look and feel. Id. at 1352. The claims were held indefinite because the interface screen may be “aesthetically pleasing” to one user but not to another. Id. at 1350.

During prosecution, the applicant may overcome a rejection by providing evidence that the meaning of the term can be ascertained by one of ordinary skill in the art when reading the disclosure, or by amending the claim to remove the subjective term.

2173.05(c)   Numerical Ranges and Amounts Limitations

Generally, the recitation of specific numerical ranges in a claim does not raise an issue of whether a claim is definite.

I.   NARROW AND BROADER RANGES IN THE SAME CLAIM

Use of a narrow numerical range that falls within a broader range in the same claim may render the claim indefinite when the boundaries of the claim are not discernible. Description of examples and preferences is properly set forth in the specification rather than in a single claim. A narrower range or preferred embodiment may also be set forth in another independent claim or in a dependent claim. If stated in a single claim, examples and preferences lead to confusion over the intended scope of the claim. In those instances where it is not clear whether the claimed narrower range is a limitation, a rejection under 35 U.S.C. 112(b) or pre-AIA 35 U.S.C. 112, second paragraph should be made. The Examiner should analyze whether the metes and bounds of the claim are clearly set forth. Examples of claim language which have been held to be indefinite are (A) “a temperature of between 45 and 78 degrees Celsius, preferably between 50 and 60 degrees Celsius”; and (B) “a predetermined quantity, for example, the maximum capacity.”

While a single claim that includes both a broad and a narrower range may be indefinite, it is not improper under 35 U.S.C. 112(b) or pre-AIA 35 U.S.C.112, second paragraph, to present a dependent claim that sets forth a narrower range for an element than the range set forth in the claim from which it depends. For example, if claim 1 reads “A circuit … wherein the resistance is 70-150 ohms.” and claim 2 reads “The circuit of claim 1 wherein the resistance is 70-100 ohms.”, then claim 2 should not be rejected as indefinite.

II.   OPEN-ENDED NUMERICAL RANGES

Open-ended numerical ranges should be carefully analyzed for definiteness. For example, when an independent claim recites a composition comprising “at least 20% sodium” and a dependent claim sets forth specific amounts of nonsodium ingredients which add up to 100%, apparently to the exclusion of sodium, an ambiguity is created with regard to the “at least” limitation (unless the percentages of the nonsodium ingredients are based on the weight of the nonsodium ingredients). On the other hand, the court held that a composition claimed to have a theoretical content greater than 100% (i.e., 20-80% of A, 20-80% of B  and 1-25% of C) was not indefinite simply because the claims may be read in theory to include compositions that are impossible in fact to formulate. It was observed that subject matter which cannot exist in fact can neither anticipate nor infringe a claim. In reKroekel, 504 F.2d 1143, 183 USPQ 610 (CCPA 1974).

In a claim directed to a chemical reaction process, a limitation required that the amount of one ingredient in the reaction mixture should “be maintained at less than 7 mole percent” based on the amount of another ingredient. The examiner argued that the claim was indefinite because the limitation sets only a maximum amount and is inclusive of substantially no ingredient resulting in termination of any reaction. The court did not agree, holding that the claim was clearly directed to a reaction process, and explaining that “[t]he imposition of a maximum limit on the quantity of one of the reactants without specifying a minimum does not warrant distorting the overall meaning of the claim to preclude performing the claimed process.”In reKirsch, 498 F.2d 1389, 1394, 182 USPQ 286, ___ (CCPA 1974).

Some terms have been determined to have the following meanings in the factual situations of the reported cases: the term “up to” includes zero as a lower limit, In reMochel, 470 F.2d 638, 176 USPQ 194 (CCPA 1974); and “a moisture content of not more than 70% by weight” reads on dry material, Ex parteKhusid, 174 USPQ 59 (Bd. App. 1971).

III.   “EFFECTIVE AMOUNT”

The common phrase “an effective amount” may or may not be indefinite. The proper test is whether or not one skilled in the art could determine specific values for the amount based on the disclosure. See In reMattison, 509 F.2d 563, 184 USPQ 484 (CCPA 1975). The phrase “an effective amount . . . for growth stimulation” was held to be definite where the amount was not critical and those skilled in the art would be able to determine from the written disclosure, including the examples, what an effective amount is. In reHalleck, 422 F.2d 911, 164 USPQ 647 (CCPA 1970). The phrase “an effective amount” has been held to be indefinite when the claim fails to state the function which is to be achieved and more than one effect can be implied from the specification or the relevant art. In reFredericksen, 213 F.2d 547, 102 USPQ 35 (CCPA 1954). The more recent cases have tended to accept a limitation such as “an effective amount” as being definite when read in light of the supporting disclosure and in the absence of any prior art which would give rise to uncertainty about the scope of the claim. In Ex parteSkuballa, 12 USPQ2d 1570 (Bd. Pat. App. & Inter. 1989), the Board held that a pharmaceutical composition claim which recited an “effective amount of a compound of claim 1” without stating the function to be achieved was definite, particularly when read in light of the supporting disclosure which provided guidelines as to the intended utilities and how the uses could be effected.

2173.05(d)   Exemplary Claim Language (“for example,” “such as”)

Description of examples or preferences is properly set forth in the specification rather than the claims. If stated in the claims, examples and preferences may lead to confusion over the intended scope of a claim. In those instances where it is not clear whether the claimed narrower range is a limitation, a rejection under 35 U.S.C. 112(b) or pre-AIA 35 U.S.C. 112, second paragraph should be made. The examiner should analyze whether the metes and bounds of the claim are clearly set forth. Note that the mere use of the phrase "such as" or "for example" in a claim does not by itself render the claim indefinite.

Examples of claim language which have been held to be indefinite because the intended scope of the claim was unclear are:

  • (A) “R is halogen, for example, chlorine”;
  • (B) “material such as rock wool or asbestos” Ex parteHall, 83 USPQ 38 (Bd. App. 1949);
  • (C) “lighter hydrocarbons, such, for example, as the vapors or gas produced” Ex parteHasche, 86 USPQ 481 (Bd. App. 1949); and
  • (D) “normal operating conditions such as while in the container of a proportioner” Ex parteSteigerwald, 131 USPQ 74 (Bd. App. 1961).

The above examples of claim language which have been held to be indefinite are fact specific and should not be applied as per se rules. See MPEP § 2173.02 for guidance regarding when it is appropriate to make a rejection under 35 U.S.C. 112(b) or pre-AIA 35 U.S.C. 112, second paragraph.

2173.05(e)   Lack of Antecedent Basis

A claim is indefinite when it contains words or phrases whose meaning is unclear. The lack of clarity could arise where a claim refers to “said lever” or “the lever,” where the claim contains no earlier recitation or limitation of a lever and where it would be unclear as to what element the limitation was making reference. Similarly, if two different levers are recited earlier in the claim, the recitation of “said lever” in the same or subsequent claim would be unclear where it is uncertain which of the two levers was intended. A claim which refers to “said aluminum lever,” but recites only “a lever” earlier in the claim, is indefinite because it is uncertain as to the lever to which reference is made. Obviously, however, the failure to provide explicit antecedent basis for terms does not always render a claim indefinite. If the scope of a claim would be reasonably ascertainable by those skilled in the art, then the claim is not indefinite. Energizer Holdings Inc. v. Int’l Trade Comm’n, 435 F.3d 1366, 77 USPQ2d 1625 (Fed. Cir. 2006) (holding that “anode gel” provided by implication the antecedent basis for “zinc anode”); Ex parte Porter, 25 USPQ2d 1144, 1145 (Bd. Pat. App. & Inter. 1992) (“controlled stream of fluid” provided reasonable antecedent basis for “the controlled fluid”). Inherent components of elements recited have antecedent basis in the recitation of the components themselves. For example, the limitation “the outer surface of said sphere” would not require an antecedent recitation that the sphere has an outer surface. See Bose Corp. v. JBL, Inc., 274 F.3d 1354, 1359, 61 USPQ2d 1216, 1218-19 (Fed. Cir 2001) (holding that recitation of “an ellipse” provided antecedent basis for “an ellipse having a major diameter” because “[t]here can be no dispute that mathematically an inherent characteristic of an ellipse is a major diameter”).

I.   EXAMINER SHOULD SUGGEST CORRECTIONS TO ANTECEDENT PROBLEMS

Antecedent problems in the claims are typically drafting oversights that are easily corrected once they are brought to the attention of applicant. The examiner’s task of making sure the claim language complies with the requirements of the statute should be carried out in a positive and constructive way, so that minor problems can be identified and easily corrected, and so that the major effort is expended on more substantive issues. However, even though indefiniteness in claim language is of semantic origin, it is not rendered unobjectionable simply because it could have been corrected. In re Hammack, 427 F.2d 1384 n.5, 166 USPQ 209 n.5 (CCPA 1970).

II.   A CLAIM TERM WHICH HAS NO ANTECEDENT BASIS IN THE DISCLOSURE IS NOT NECESSARILY INDEFINITE

The mere fact that a term or phrase used in the claim has no antecedent basis in the specification disclosure does not mean, necessarily, that the term or phrase is indefinite. There is no requirement that the words in the claim must match those used in the specification disclosure. Applicants are given a great deal of latitude in how they choose to define their invention so long as the terms and phrases used define the invention with a reasonable degree of clarity and precision.

III.   A CLAIM IS NOT PER SE INDEFINITE IF THE BODY OF THE CLAIM RECITES ADDITIONAL ELEMENTS WHICH DO NOT APPEAR IN THE PREAMBLE

The mere fact that the body of a claim recites additional elements which do not appear in the claim’s preamble does not render the claim indefinite under 35 U.S.C. 112(b) or pre-AIA 35 U.S.C. 112, second paragraph. See In re Larsen, No. 01-1092 (Fed. Cir. May 9, 2001) (unpublished) (The preamble of the Larsen claim recited only a hanger and a loop but the body of the claim positively recited a linear member. The examiner rejected the claim under 35 U.S.C. 112, second paragraph, because the omission from the claim’s preamble of a critical element (i.e., a linear member) renders that claim indefinite. The court reversed the examiner’s rejection and stated that the totality of all the limitations of the claim and their interaction with each other must be considered to ascertain the inventor’s contribution to the art. Upon review of the claim in its entirety, the court concluded that the claim at issue apprises one of ordinary skill in the art of its scope and, therefore, serves the notice function required by 35 U.S.C. 112, paragraph 2.).

2173.05(f)   Reference to Limitations in Another Claim

A claim which makes reference to a preceding claim to define a limitation is an acceptable claim construction which should not necessarily be rejected as improper or confusing under 35 U.S.C. 112(b) or pre-AIA 35 U.S.C. 112, second paragraph. For example, claims which read: “The product produced by the method of claim 1.” or “A method of producing ethanol comprising contacting amylose with the culture of claim 1 under the following conditions .....” are not indefinite under 35 U.S.C. 112(b) or pre-AIA 35 U.S.C. 112, second paragraph, merely because of the reference to another claim. See also Ex partePorter, 25 USPQ2d 1144 (Bd. Pat. App. & Inter. 1992) (where reference to “the nozzle of claim 7” in a method claim was held to comply with 35 U.S.C. 112, second paragraph). However, where the format of making reference to limitations recited in another claim results in confusion, then a rejection would be proper under 35 U.S.C. 112(b) or pre-AIA 35 U.S.C. 112, second paragraph.

When examining a dependent claim, the examiner should also determine whether the claim complies with 35 U.S.C. 112(d) or pre-AIA 35 U.S.C. 112, fourth paragraph. See MPEP § 608.01(n), subsection II.

2173.05(g)   Functional Limitations

A claim term is functional when it recites a feature “by what it does rather than by what it is” (e.g., as evidenced by its specific structure or specific ingredients). In reSwinehart, 439 F.2d 210, 212, 169 USPQ 226, 229 (CCPA 1971). There is nothing inherently wrong with defining some part of an invention in functional terms. Functional language does not, in and of itself, render a claim improper. Id. In fact, 35 U.S.C. 112(f) and pre-AIA 35 U.S.C. 112, sixth paragraph, expressly authorize a form of functional claiming (means- (or step-) plus- function claim limitations discussed in MPEP § 2181et seq.). Functional language may also be employed to limit the claims without using the means-plus-function format. See, e.g., K-2 Corp. v. Salomon S.A., 191 F.3d 1356, 1363 (Fed. Cir. 1999). Unlike means-plus-function claim language that applies only to purely functional limitations, Phillips v. AWH Corp, 415 F.3d 1303, 1311 (Fed. Cir. 2005) (en banc) (“Means-plus-function claiming applies only to purely functional limitations that do not provide the structure that performs the recited function.”), functional claiming often involves the recitation of some structure followed by its function. For example, in In re Schreiber, the claims were directed to a conical spout (the structure) that “allow[ed] several kernels of popped popcorn to pass through at the same time” (the function). In re Schreiber, 128 F.3d 1473, 1478 (Fed. Cir. 1997). As noted by the court in Schreiber, “[a] patent applicant is free to recite features of an apparatus either structurally or functionally.” Id.

A functional limitation must be evaluated and considered, just like any other limitation of the claim, for what it fairly conveys to a person of ordinary skill in the pertinent art in the context in which it is used. A functional limitation is often used in association with an element, ingredient, or step of a process to define a particular capability or purpose that is served by the recited element, ingredient or step. In Innova/Pure Water Inc. v. Safari Water Filtration Sys. Inc., 381 F.3d 1111, 1117-20, 72 USPQ2d 1001, 1006-08 (Fed. Cir. 2004), the court noted that the claim term “operatively connected” is “a general descriptive claim term frequently used in patent drafting to reflect a functional relationship between claimed components,” that is, the term “means the claimed components must be connected in a way to perform a designated function.” “In the absence of modifiers, general descriptive terms are typically construed as having their full meaning.” Id. at 1118, 72 USPQ2d at 1006. In the patent claim at issue, “subject to any clear and unmistakable disavowal of claim scope, the term ‘operatively connected’ takes the full breath of its ordinary meaning, i.e., ‘said tube [is] operatively connected to said cap’ when the tube and cap are arranged in a manner capable of performing the function of filtering.” Id. at 1120, 72 USPQ2d at 1008.

Other examples of permissible function language:

It was held that the limitation used to define a radical on a chemical compound as “incapable of forming a dye with said oxidizing developing agent” although functional, was perfectly acceptable because it set definite boundaries on the patent protection sought. In reBarr, 444 F.2d 588, 170 USPQ 330(CCPA 1971).

In a claim that was directed to a kit of component parts capable of being assembled, the Court held that limitations such as “members adapted to be positioned” and “portions . . . being resiliently dilatable whereby said housing may be slidably positioned” serve to precisely define present structural attributes of interrelated component parts of the claimed assembly. In reVenezia, 530 F.2d 956, 189 USPQ 149 (CCPA 1976).

Notwithstanding the permissible instances, the use of functional language in a claim may fail “to provide a clear-cut indication of the scope of the subject matter embraced by the claim” and thus be indefinite. In re Swinehart, 439 F.2d 210, 213 (CCPA 1971). For example, when claims merely recite a description of a problem to be solved or a function or result achieved by the invention, the boundaries of the claim scope may be unclear. Halliburton Energy Servs., Inc. v. M-I LLC, 514 F.3d 1244, 1255, 85 USPQ2d 1654, 1663 (Fed. Cir. 2008) (noting that the Supreme Court explained that a vice of functional claiming occurs “when the inventor is painstaking when he recites what has already been seen, and then uses conveniently functional language at the exact point of novelty”) (quoting General Elec. Co. v. Wabash Appliance Corp., 304 U.S. 364, 371 (1938)); see also United Carbon Co. v. Binney & Smith Co., 317 U.S. 228, 234 (1942) (holding indefinite claims that recited substantially pure carbon black “in the form of commercially uniform, comparatively small, rounded smooth aggregates having a spongy or porous exterior”). Further, without reciting the particular structure, materials or steps that accomplish the function or achieve the result, all means or methods of resolving the problem may be encompassed by the claim. Ariad Pharmaceuticals., Inc. v. Eli Lilly & Co., 598 F.3d 1336, 1353, 94 USPQ2d 1161, 1173 (Fed. Cir. 2010) (en banc). Unlimited functional claim limitations that extend to all means or methods of resolving a problem may not be adequately supported by the written description or may not be commensurate in scope with the enabling disclosure, both of which are required by 35 U.S.C. 112(a) and pre-AIA 35 U.S.C. 112, first paragraph. In re Hyatt, 708 F.2d 712, 714, 218 USPQ 195, 197 (Fed. Cir. 1983); Ariad, 598 F.3d at 1340, 94 USPQ2d at 1167. For instance, a single means claim covering every conceivable means for achieving the stated result was held to be invalid under 35 U.S.C. 112, first paragraph because the court recognized that the specification, which disclosed only those means known to the inventor, was not commensurate in scope with the claim. Hyatt, 708 F.2d at 714-715, 218 USPQ at 197. For more information regarding the written description requirement and enablement requirement under 35 U.S.C. 112(a) or pre-AIA 35 U.S.C. 112, first paragraph, see MPEP §§ 2161-2164.08(c). keeping in mind that whether or not the functional limitation complies with 35 U.S.C. 112(a) or pre-AIA 35 U.S.C. 112, second paragraph, is a different issue from whether the limitation is properly supported under 35 U.S.C. 112(a) or pre-AIA 35 U.S.C. 112, first paragraph, or is distinguished over the prior art.

When a claim limitation employs functional language, the examiner’s determination of whether the limitation is sufficiently definite will be highly dependent on context (e.g., the disclosure in the specification and the knowledge of a person of ordinary skill in the art). Halliburton Energy Servs., 514 F.3d at 1255, 85 USPQ2d at 1663. For example, a claim that included the term “fragile gel” was found to be indefinite because the definition of the term in the specification was functional, i.e., the fluid is defined by what it does rather than what it is (“ability of the fluid to transition quickly from gel to liquid, and the ability of the fluid to suspend drill cuttings at rest”), and it was ambiguous as to the requisite degree of the fragileness of the gel, the ability of the gel to suspend drill cuttings (i.e., gel strength), and/or some combination of the two. Halliburton Energy Servs., 514 F.3d at 1255-56, 85 USPQ2d at 1663. In another example, the claims directed to a tungsten filament for electric incandescent lamps were held invalid for including a limitation that recited “comparatively large grains of such size and contour as to prevent substantial sagging or offsetting during a normal or commercially useful life for such a lamp or other device.” General Elec. Co., 304 U.S. at 370-71, 375. The Court observed that the prior art filaments also “consisted of comparatively large crystals” but they were “subject to offsetting” or shifting, and the court further found that the phrase “of such size and contour as to prevent substantial sagging and offsetting during a normal or commercially useful life for a lamp or other device” did not adequately define the structural characteristics of the grains (e.g., the size and contour) to distinguish the claimed invention from the prior art.Id. at 370. Similarly, a claim was held invalid because it recited “sustantially (sic) pure carbon black in the form of commercially uniform, comparatively small, rounded smooth aggregates having a spongy or porous exterior.” United Carbon Co., 317 U.S. at 234. In the latter example, the Court observed various problems with the limitation: “commercially uniform” meant only the degree of uniformity buyers desired; “comparatively small” did not add anything because no standard for comparison was given; and “spongy” and “porous” are synonyms that the Court found unhelpful in distinguishing the claimed invention from the prior art. Id. at 233.

In comparison, a claim limitation reciting “transparent to infrared rays” was held to be definite because the specification showed that a substantial amount of infrared radiation was always transmitted even though the degree of transparency varied depending on certain factors. Swinehart, 439 F.2d at 214, 169 USPQ at 230. Likewise, the claims in another case were held definite because applicant provided “a general guideline and examples sufficient to enable a person of ordinary skill in the art to determine whether a process uses a silicon dioxide source ‘essentially free of alkali metal’ to make a reaction mixture ‘essentially free of alkali metal’ to produce a zeolitic compound ‘essentially free of alkali metal.’” In re Marosi, 710 F.2d 799, 803, 218 USPQ 289, 293 (Fed. Cir. 1983).

Examiners should consider the following factors when examining claims that contain functional language to determine whether the language is ambiguous: (1) whether there is a clear cut indication of the scope of the subject matter covered by the claim; (2) whether the language sets forth well-defined boundaries of the invention or only states a problem solved or a result obtained; and (3) whether one of ordinary skill in the art would know from the claim terms what structure or steps are encompassed by the claim. These factors are examples of points to be considered when determining whether language is ambiguous and are not intended to be all inclusive or limiting. Other factors may be more relevant for particular arts. The primary inquiry is whether the language leaves room for ambiguity or whether the boundaries are clear and precise.

During prosecution, applicant may resolve the ambiguities of a functional limitation in a number of ways. For example: (1) “the ambiguity might be resolved by using a quantitative metric (e.g., numeric limitation as to a physical property) rather than a qualitative functional feature” (see Halliburton Energy Servs., 514 F.3d at 1255-56, 85 USPQ2d at 1663); (2) applicant could demonstrate that the “specification provide[s] a formula for calculating a property along with examples that meet the claim limitation and examples that do not” (see id. at 1256, 85 USPQ2d at 1663 (citing Oakley, Inc. v. Sunglass Hut Int’l, 316 F.3d 1331, 1341, 65 USPQ2d 1321, 1326 (Fed. Cir. 2003))); (3) applicant could demonstrate that the specification provides a general guideline and examples sufficient to teach a person skilled in the art when the claim limitation was satisfied (see Marosi, 710 F.2d at 803, 218 USPQ at 292); or (4) applicant could amend the claims to recite the particular structure that accomplishes the function.

2173.05(h)   Alternative Limitations

I.   MARKUSH GROUPS

Alternative expressions are permitted if they present no uncertainty or ambiguity with respect to the question of scope or clarity of the claims. A “Markush” claim recites a list of alternatively useable species. In re Harnisch, 631 F.2d 716, 719-20, 206 USPQ 300, 303-04 (CCPA 1980); Ex parte Markush, 1925 Dec. Comm’r Pat. 126, 127 (1924). A Markush claim is commonly formatted as: “selected from the group consisting of A, B, and C;” however, the phrase “Markush claim” means any claim that recites a list of alternatively useable species regardless of format.

Ex parte Markush sanctions claiming a genus expressed as a group consisting of certain specified materials. Inventions in metallurgy, refractories, ceramics, pharmacy, pharmacology and biology are most frequently claimed under the Markush formula but purely mechanical features or process steps may also be claimed by using the Markush style of claiming. See Ex parteHead, 214 USPQ 551 (Bd. App. 1981); In reGaubert, 524 F.2d 1222, 187 USPQ 664 (CCPA 1975); In reHarnisch, 631 F.2d 716, 206 USPQ 300 (CCPA 1980). It is improper to use the term “comprising” instead of “consisting of.” Ex parteDotter, 12 USPQ 382 (Bd. App. 1931).

The use of Markush claims of diminishing scope should not, in itself, be considered a sufficient basis for objection to or rejection of claims. However, if such a practice renders the claims indefinite or if it results in undue multiplicity, an appropriate rejection should be made.

A Markush claim may encompass a large number of alternative species, but is not necessarily indefinite under 35 U.S.C. 112(b) or pre-AIA 35 U.S.C. 112, second paragraph for such breadth. In re Gardner, 427 F.2d 786, 788 (CCPA 1970) (“Breadth is not indefiniteness.”). In certain circumstances, however, a Markush group may be so expansive that persons skilled in the art cannot determine the metes and bounds of the claimed invention. For example, a Markush group that encompasses a massive number of distinct alternative species may be indefinite under 35 U.S.C. 112(b) or pre-AIA 35 U.S.C. 112, second paragraph if one skilled in the art cannot determine the metes and bounds of the claim due to an inability to envision all of the members of the Markush group. In such a circumstance, an examiner may reject the claim for indefiniteness under 35 U.S.C. 112(b) or pre-AIA 35 U.S.C. 112, second paragraph.

Similarly, the double inclusion of an element by members of a Markush group is not, in itself, sufficient basis for objection to or rejection of claims. Rather, the facts in each case must be evaluated to determine whether or not the multiple inclusion of one or more elements in a claim renders that claim indefinite. The mere fact that a compound may be embraced by more than one member of a Markush group recited in the claim does not necessarily render the scope of the claim unclear. For example, the Markush group, “selected from the group consisting of amino, halogen, nitro, chloro and alkyl” should be acceptable even though “halogen” is generic to “chloro.”

The materials set forth in the Markush group ordinarily must belong to a recognized physical or chemical class or to an art-recognized class. However, when the Markush group occurs in a claim reciting a process or a combination (not a single compound), it is sufficient if the members of the group are disclosed in the specification to possess at least one property in common which is mainly responsible for their function in the claimed relationship, and it is clear from their very nature or from the prior art that all of them possess this property. While in the past the test for Markush-type claims was applied as liberally as possible, present practice which holds that claims reciting Markush groups are not generic claims (MPEP § 803) may subject the groups to a more stringent test for propriety of the recited members. Where a Markush expression is applied only to a portion of a chemical compound, the propriety of the grouping is determined by a consideration of the compound as a whole, and does not depend on there being a community of properties in the members of the Markush expression.

When materials recited in a claim are so related as to constitute a proper Markush group, they may be recited in the conventional manner, or alternatively. For example, if “wherein R is a material selected from the group consisting of A, B, C and D” is a proper limitation, then “wherein R is A, B, C or D” shall also be considered proper.

  Subgenus Claim

Genus, subgenus, and Markush-type claims, if properly supported by the disclosure, are all acceptable ways for applicants to claim their inventions. They provide different ways to present claims of different scope. Examiners should therefore not reject Markush-type claims merely because there are genus claims that encompass the Markush-type claims.

See also MPEP § 608.01(p) and § 715.03.

See MPEP § 803.02 for restriction practice re Markush-type claims.

II.   “OR” TERMINOLOGY

Alternative expressions using “or” are acceptable, such as “wherein R is A, B, C, or D.” The following phrases were each held to be acceptable and not in violation of 35 U.S.C. 112, second paragraph in In reGaubert, 524 F.2d 1222, 187 USPQ 664 (CCPA 1975): “made entirely or in part of”; “at least one piece”; and “iron, steel or any other magnetic material.”

III.   “OPTIONALLY”

An alternative format which requires some analysis before concluding whether or not the language is indefinite involves the use of the term “optionally.” In Ex parteCordova, 10 USPQ2d 1949 (Bd. Pat. App. & Inter. 1989) the language “containing A, B, and optionally C” was considered acceptable alternative language because there was no ambiguity as to which alternatives are covered by the claim. A similar holding was reached with regard to the term “optionally” in Ex parteWu, 10 USPQ2d 2031 (Bd. Pat. App. & Inter. 1989). In the instance where the list of potential alternatives can vary and ambiguity arises, then it is proper to make a rejection under 35 U.S.C. 112(b) or pre-AIA 35 U.S.C. 112, second paragraph, and explain why there is confusion.

2173.05(i)   Negative Limitations

The current view of the courts is that there is nothing inherently ambiguous or uncertain about a negative limitation. So long as the boundaries of the patent protection sought are set forth definitely, albeit negatively, the claim complies with the requirements of 35 U.S.C. 112(b) or pre-AIA 35 U.S.C. 112, second paragraph. Some older cases were critical of negative limitations because they tended to define the invention in terms of what it was not, rather than pointing out the invention. Thus, the court observed that the limitation “R is an alkenyl radical other than 2-butenyl and 2,4-pentadienyl” was a negative limitation that rendered the claim indefinite because it was an attempt to claim the invention by excluding what the inventors did not invent rather than distinctly and particularly pointing out what they did invent. In re Schechter, 205 F.2d 185, 98 USPQ 144 (CCPA 1953).

A claim which recited the limitation “said homopolymer being free from the proteins, soaps, resins, and sugars present in natural Hevea rubber” in order to exclude the characteristics of the prior art product, was considered definite because each recited limitation was definite. In re Wakefield, 422 F.2d 897, 899, 904, 164 USPQ 636, 638, 641 (CCPA 1970). In addition, the court found that the negative limitation “incapable of forming a dye with said oxidized developing agent” was definite because the boundaries of the patent protection sought were clear. In re Barr, 444 F.2d 588, 170 USPQ 330 (CCPA 1971).

Any negative limitation or exclusionary proviso must have basis in the original disclosure. If alternative elements are positively recited in the specification, they may be explicitly excluded in the claims. See In re Johnson, 558 F.2d 1008, 1019, 194 USPQ 187, 196 (CCPA 1977) (“[the] specification, having described the whole, necessarily described the part remaining.”). See also Ex parte Grasselli, 231 USPQ 393 (Bd. App. 1983), aff’d mem., 738 F.2d 453 (Fed. Cir. 1984). The mere absence of a positive recitation is not basis for an exclusion. Any claim containing a negative limitation which does not have basis in the original disclosure should be rejected under 35 U.S.C. 112(a) or pre-AIA 35 U.S.C. 112, first paragraph, as failing to comply with the written description requirement. Note that a lack of literal basis in the specification for a negative limitation may not be sufficient to establish a prima facie case for lack of descriptive support. Ex parte Parks, 30 USPQ2d 1234, 1236 (Bd. Pat. App. & Inter. 1993). See MPEP § 2163 - § 2163.07(b) for a discussion of the written description requirement of 35 U.S.C. 112(a) and pre-AIA 35 U.S.C. 112, first paragraph.

2173.05(j)   Old Combination

  A CLAIM SHOULD NOT BE REJECTED ON THE GROUND OF OLD COMBINATION

With the passage of the 1952 Patent Act, the courts and the Board have taken the view that a rejection based on the principle of old combination is NO LONGER VALID. Claims should be considered proper so long as they comply with the provisions of 35 U.S.C. 112(b) or pre-AIA 35 U.S.C. 112, second paragraph.

A rejection on the basis of old combination was based on the principle applied in Lincoln Engineering Co. v. Stewart-Warner Corp., 303 U.S. 545, 37 USPQ 1 (1938). The principle was that an inventor who made an improvement or contribution to but one element of a generally old combination, should not be able to obtain a patent on the entire combination including the new and improved element. A rejection required the citation of a single reference which broadly disclosed a combination of the claimed elements functionally cooperating in substantially the same manner to produce substantially the same results as that of the claimed combination. The case of In re Hall, 208 F.2d 370, 100 USPQ 46 (CCPA 1953) illustrates an application of this principle.

The court pointed out in In re Bernhart, 417 F.2d 1395, 163 USPQ 611 (CCPA 1969) that the statutory language (particularly point out and distinctly claim) is the only proper basis for an old combination rejection, and in applying the rejection, that language determines what an applicant has a right and obligation to do. A majority opinion of the Board of Appeals held that Congress removed the underlying rationale of Lincoln Engineering in the 1952 Patent Act, and thereby effectively legislated that decision out of existence. Ex parte Barber, 187 USPQ 244 (Bd. App. 1974). Finally, the Court of Appeals for the Federal Circuit, in Radio Steel and Mfg. Co. v. MTD Products, Inc., 731 F.2d 840, 221 USPQ 657 (Fed. Cir. 1984), followed the Bernhart case, and ruled that a claim was not invalid under Lincoln Engineering because the claim complied with the requirements of 35 U.S.C. 112, second paragraph. Accordingly, a claim should not be rejected on the ground of old combination.

2173.05(k)   Aggregation

A claim should not be rejected on the ground of “aggregation.” In re Gustafson, 331 F.2d 905, 141 USPQ 585 (CCPA 1964) (an applicant is entitled to know whether the claims are being rejected under 35 U.S.C. 101, 102, 103, or 112); In re Collier, 397 F.2d 1003, 1006, 158 USPQ 266, 268 (CCPA 1968) (“[A] rejection for ‘aggregation’ is non-statutory.”).

If a claim omits essential matter or fails to interrelate essential elements of the invention as defined by applicant(s) in the specification, see MPEP § 2172.01.

2173.05(l)   [Reserved]

2173.05(m)    Prolix

Examiners should reject claims as prolix only when they contain such long recitations or unimportant details that the scope of the claimed invention is rendered indefinite thereby. Claims are rejected as prolix when they contain long recitations that the metes and bounds of the claimed subject matter cannot be determined.

2173.05(n)   Multiplicity

37 C.F.R. 1.75   Claim(s).

  • (a) The specification must conclude with a claim particularly pointing out and distinctly claiming the subject matter which the applicant regards as his invention or discovery.
  • (b) More than one claim may be presented provided they differ substantially from each other and are not unduly multiplied.

*****

Where, in view of the nature and scope of applicant’s invention, applicant presents an unreasonable number of claims which are repetitious and multiplied, the net result of which is to confuse rather than to clarify, a rejection on undue multiplicity based on 35 U.S.C. 112(b) or pre-AIA 35 U.S.C. 112, second paragraph, may be appropriate. As noted by the court in In re Chandler, 319 F.2d 211, 225, 138 USPQ 138, 148 (CCPA 1963), “applicants should be allowed reasonable latitude in stating their claims in regard to number and phraseology employed. The right of applicants to freedom of choice in selecting phraseology which truly points out and defines their inventions should not be abridged. Such latitude, however, should not be extended to sanction that degree of repetition and multiplicity which beclouds definition in a maze of confusion. The rule of reason should be practiced and applied on the basis of the relevant facts and circumstances in each individual case.” See also In re Flint, 411 F.2d 1353, 1357, 162 USPQ 228, 231 (CCPA 1969). Undue multiplicity rejections based on 35 U.S.C. 112(b) or pre-AIA 35 U.S.C. 112, second paragraph, should be applied judiciously and should be rare.

If an undue multiplicity rejection under 35 U.S.C. 112(b) or pre-AIA 35 U.S.C. 112, second paragraph, is appropriate, the examiner should contact applicant by telephone explaining that the claims are unduly multiplied and will be rejected under 35 U.S.C. 112(b) or pre-AIA 35 U.S.C. 112, second paragraph. Note MPEP § 408. The examiner should also request that applicant select a specified number of claims for purpose of examination. If applicant is willing to select, by telephone, the claims for examination, an undue multiplicity rejection on all the claims based on 35 U.S.C. 112(b) or pre-AIA 35 U.S.C. 112, second paragraph, should be made in the next Office action along with an action on the merits on the selected claims. If applicant refuses to comply with the telephone request, an undue multiplicity rejection of all the claims based on 35 U.S.C. 112(b) or pre-AIA 35 U.S.C. 112, second paragraph, should be made in the next Office action. Applicant’s reply must include a selection of claims for purpose of examination, the number of which may not be greater than the number specified by the examiner. In response to applicant’s reply, if the examiner adheres to the undue multiplicity rejection, it should be repeated and the selected claims will be examined on the merits. This procedure preserves applicant’s right to have the rejection on undue multiplicity reviewed by the Patent Trail and Appeal Board.

Also, it is possible to reject one claim over an allowed claim if they differ only by subject matter old in the art. This ground of rejection is set forth in Ex parteWhitelaw, 1915 C.D. 18, 219 O.G. 1237 (Comm’r Pat. 1914). The Ex parteWhitelaw doctrine is restricted to cases where the claims are unduly multiplied or are substantial duplicates. Ex parte Kochan, 131 USPQ 204, 206 (Bd. App. 1961).

2173.05(o)   Double Inclusion

There is no per se rule that “double inclusion” is improper in a claim. In re Kelly, 305 F.2d 909, 916, 134 USPQ 397, 402 (CCPA 1962) (“Automatic reliance upon a ‘rule against double inclusion’ will lead to as many unreasonable interpretations as will automatic reliance upon a ‘rule allowing double inclusion’. The governing consideration is not double inclusion, but rather is what is a reasonable construction of the language of the claims.”). Older cases, such as Ex parte White, 759 O.G. 783 (Bd. App. 1958) and Ex parte Clark, 174 USPQ 40 (Bd. App. 1971) should be applied with care, according to the facts of each case.

The facts in each case must be evaluated to determine whether or not the multiple inclusion of one or more elements in a claim gives rise to indefiniteness in that claim. The mere fact that a compound may be embraced by more than one member of a Markush group recited in the claim does not lead to any uncertainty as to the scope of that claim for either examination or infringement purposes. On the other hand, where a claim directed to a device can be read to include the same element twice, the claim may be indefinite. Ex parte Kristensen, 10 USPQ2d 1701 (Bd. Pat. App. & Inter. 1989).

2173.05(p)   Claim Directed to Product-By- Process or Product and Process

There are many situations where claims are permissively drafted to include a reference to more than one statutory class of invention.

I.   PRODUCT-BY-PROCESS

A product-by-process claim, which is a product claim that defines the claimed product in terms of the process by which it is made, is proper. In re Luck, 476 F.2d 650, 177 USPQ 523 (CCPA 1973); In re Pilkington, 411 F.2d 1345, 162 USPQ 145 (CCPA 1969); In re Steppan, 394 F.2d 1013, 156 USPQ 143 (CCPA 1967). A claim to a device, apparatus, manufacture, or composition of matter may contain a reference to the process in which it is intended to be used without being objectionable under 35 U.S.C. 112(b) or pre-AIA 35 U.S.C. 112, second paragraph, so long as it is clear that the claim is directed to the product and not the process.

An applicant may present claims of varying scope even if it is necessary to describe the claimed product in product-by-process terms. Ex partePantzer, 176 USPQ 141 (Bd. App. 1972).

II.   PRODUCT AND PROCESS IN THE SAME CLAIM

A single claim which claims both an apparatus and the method steps of using the apparatus is indefinite under 35 U.S.C. 112(b) or pre-AIA 35 U.S.C. 112, second paragraph. See In re Katz Interactive Call Processing Patent Litigation, 639 F.3d 1303, 97 USPQ2d 1737 (Fed. Cir. 2011). In Katz, a claim directed to “[a] system with an interface means for providing automated voice messages…to certain of said individual callers, wherein said certain of said individual callers digitally enter data” was determined to be indefinite because the italicized claim limitation is not directed to the system, but rather to actions of the individual callers, which creates confusion as to when direct infringement occurs. Katz, 639 F.3d at 1318 (citing IPXL Holdings v. Amazon.com, Inc., 430 F.2d 1377, 1384, 77 USPQ2d 1140, 1145 (Fed. Cir. 2005), in which a system claim that recited “an input means” and required a user to use the input means was found to be indefinite because it was unclear “whether infringement … occurs when one creates a system that allows the user [to use the input means], or whether infringement occurs when the user actually uses the input means.”); Ex parteLyell, 17 USPQ2d 1548 (Bd. Pat. App. & Inter. 1990) (claim directed to an automatic transmission workstand and the method of using it held ambiguous and properly rejected under 35 U.S.C. 112, second paragraph).

2173.05(q)   “Use” Claims

Attempts to claim a process without setting forth any steps involved in the process generally raises an issue of indefiniteness under 35 U.S.C. 112(b) or pre-AIA 35 U.S.C. 112, second paragraph. For example, a claim which read: “[a] process for using monoclonal antibodies of claim 4 to isolate and purify human fibroblast interferon” was held to be indefinite because it merely recites a use without any active, positive steps delimiting how this use is actually practiced. Ex parteErlich, 3 USPQ2d 1011 (Bd. Pat. App. & Inter. 1986).

Other decisions suggest that a more appropriate basis for this type of rejection is 35 U.S.C. 101. In Ex parteDunki, 153 USPQ 678 (Bd. App. 1967), the Board held the following claim to be an improper definition of a process: “The use of a high carbon austenitic iron alloy having a proportion of free carbon as a vehicle brake part subject to stress by sliding friction.” In Clinical Products Ltd. v. Brenner, 255 F. Supp. 131, 149 USPQ 475 (D.D.C. 1966), the district court held the following claim was definite, but that it was not a proper process claim under 35 U.S.C. 101: “The use of a sustained release therapeutic agent in the body of ephedrine absorbed upon polystyrene sulfonic acid.”

Although a claim should be interpreted in light of the specification disclosure, it is generally considered improper to read limitations contained in the specification into the claims. See In rePrater, 415 F.2d 1393, 162 USPQ 541 (CCPA 1969) and In re Winkhaus, 527 F.2d 637, 188 USPQ 129 (CCPA 1975), which discuss the premise that one cannot rely on the specification to impart limitations to the claim that are not recited in the claim.

I.   A “USE” CLAIM SHOULD BE REJECTED UNDER ALTERNATIVE GROUNDS BASED ON 35 U.S.C 101 AND 112

In view of the split of authority as discussed above, the most appropriate course of action would be to reject a “use” claim under alternative grounds based on 35 U.S.C. 101 and 112 .

II.   BOARD HELD STEP OF “UTILIZING” WAS NOT INDEFINITE

It is often difficult to draw a fine line between what is permissible, and what is objectionable from the perspective of whether a claim is definite. In the case of Ex partePorter, 25 USPQ2d 1144 (Bd. Pat. App. & Inter. 1992), the Board held that a claim which clearly recited the step of “utilizing” was not indefinite under 35 U.S.C. 112, second paragraph. (Claim was to “A method for unloading nonpacked, nonbridging and packed, bridging flowable particle catalyst and bead material from the opened end of a reactor tube which comprises utilizing the nozzle of claim 7.”).

2173.05(r)   Omnibus Claim

Some applications are filed with an omnibus claim which reads as follows: A device substantially as shown and described. This claim should be rejected under 35 U.S.C. 112(b) or pre-AIA 35 U.S.C. 112, second paragraph, because it is indefinite in that it fails to point out what is included or excluded by the claim language. See Ex parteFressola, 27 USPQ2d 1608 (Bd. Pat. App. & Inter. 1993), for a discussion of the history of omnibus claims and an explanation of why omnibus claims do not comply with the requirements of 35 U.S.C. 112(b) or pre-AIA 35 U.S.C. 112, second paragraph.

Such a claim can be rejected using form paragraph 7.35. See MPEP § 706.03(d).

For cancellation of such a claim by examiner’s amendment, see MPEP § 1302.04(b).

2173.05(s)   Reference to Figures or Tables

Where possible, claims are to be complete in themselves. Incorporation by reference to a specific figure or table “is permitted only in exceptional circumstances where there is no practical way to define the invention in words and where it is more concise to incorporate by reference than duplicating a drawing or table into the claim. Incorporation by reference is a necessity doctrine, not for applicant’s convenience.” Ex parteFressola, 27 USPQ2d 1608, 1609 (Bd. Pat. App. & Inter. 1993) (citations omitted).

Reference characters corresponding to elements recited in the detailed description and the drawings may be used in conjunction with the recitation of the same element or group of elements in the claims. See MPEP § 608.01(m).

2173.05(t)   Chemical Formula

Claims to chemical compounds and compositions containing chemical compounds often use formulas that depict the chemical structure of the compound. These structures should not be considered indefinite nor speculative in the absence of evidence that the assigned formula is in error. The absence of corroborating spectroscopic or other data cannot be the basis for finding the structure indefinite. See Ex parteMorton, 134 USPQ 407 (Bd. App. 1961), and Ex parteSobin, 139 USPQ 528 (Bd. App. 1962).

A claim to a chemical compound is not indefinite merely because a structure is not presented or because a partial structure is presented. For example, the claim language at issue in In reFisher, 427 F.2d 833, 166 USPQ 18 (CCPA 1970) referred to a chemical compound as a “polypeptide of at least 24 amino acids having the following sequence.” A rejection under pre-AIA 35 U.S.C. 112, second paragraph, for failure to identify the entire structure was reversed and the court held: “While the absence of such a limitation obviously broadens the claim and raises questions of sufficiency of disclosure, it does not render the claim indefinite.” Chemical compounds may be claimed by a name that adequately describes the material to one skilled in the art. See Martinv.Johnson, 454 F.2d 746, 172 USPQ 391 (CCPA 1972). A compound of unknown structure may be claimed by a combination of physical and chemical characteristics. See Ex parteBrian, 118 USPQ 242 (Bd. App. 1958). A compound may also be claimed in terms of the process by which it is made without raising an issue of indefiniteness.

2173.05(u)   Trademarks or Trade Names in a Claim

The presence of a trademark or trade name in a claim is not, per se, improper under 35 U.S.C. 112(b) or pre-AIA 35 U.S.C. 112, second paragraph, but the claim should be carefully analyzed to determine how the mark or name is used in the claim. It is important to recognize that a trademark or trade name is used to identify a source of goods, and not the goods themselves. Thus a trademark or trade name does not identify or describe the goods associated with the trademark or trade name. See definitions of trademark and trade name in MPEP § 608.01(v).

If the trademark or trade name is used in a claim as a limitation to identify or describe a particular material or product, the claim does not comply with the requirements of the 35 U.S.C. 112(b) or pre-AIA 35 U.S.C. 112, second paragraph. Ex parteSimpson, 218 USPQ 1020 (Bd. App. 1982). The claim scope is uncertain since the trademark or trade name cannot be used properly to identify any particular material or product. In fact, the value of a trademark would be lost to the extent that it became descriptive of a product, rather than used as an identification of a source or origin of a product. Thus, the use of a trademark or trade name in a claim to identify or describe a material or product would not only render a claim indefinite, but would also constitute an improper use of the trademark or trade name.

If a trademark or trade name appears in a claim and is not intended as a limitation in the claim, the question of why it is in the claim should be addressed. If its presence in the claim causes confusion as to the scope of the claim, then the claim should be rejected under 35 U.S.C. 112(b) or pre-AIA 35 U.S.C. 112, second paragraph.

2173.05(v)   Mere Function of Machine

Process or method claims are not subject to rejection by U.S. Patent and Trademark Office examiners under 35 U.S.C. 112(b) or pre-AIA 35 U.S.C. 112, second paragraph, solely on the ground that they define the inherent function of a disclosed machine or apparatus. In reTarczy-Hornoch, 397 F.2d 856, 158 USPQ 141 (CCPA 1968). The court in Tarczy-Hornoch held that a process claim, otherwise patentable, should not be rejected merely because the application of which it is a part discloses an apparatus which will inherently carry out the recited steps.

2173.06    Practice Compact Prosecution [R-11.2013]

I.   INTERPRET THE CLAIM AND APPLY ART WITH AN EXPLANATION OF HOW AN INDEFINITE TERM IS INTERPRETED

The goal of examination is to clearly articulate any rejection early in the prosecution process so that the applicant has the chance to provide evidence of patentability and otherwise reply completely at the earliest opportunity. See MPEP § 706. Under the principles of compact prosecution, the examiner should review each claim for compliance with every statutory requirement for patentability in the initial review of the application and identify all of the applicable grounds of rejection in the first Office action to avoid unnecessary delays in the prosecution of the application. See 37 CFR 1.104(a)(1) (“On taking up an application for examination or a patent in a reexamination proceeding, the examiner shall make a thorough study thereof and shall make a thorough investigation of the available prior art relating to the subject matter of the claimed invention. The examination shall be complete with respect both to compliance of the application . . . with the applicable statutes and rules and to the patentability of the invention as claimed, as well as with respect to matters of form, unless otherwise indicated.”).

Thus, when the examiner determines that a claim term or phrase renders the claim indefinite, the examiner should make a rejection based on indefiniteness under 35 U.S.C. 112(b) or pre-AIA 35 U.S.C. 112, second paragraph, as well as a rejection(s) in view of the prior art under 35 U.S.C. 102 or 103 that renders the prior art applicable based on the examiner’s interpretation of the claim. When making a rejection over prior art in these circumstances, it is important that the examiner state on the record how the claim term or phrase is being interpreted with respect to the prior art applied in the rejection. By rejecting each claim on all reasonable grounds available, the examiner can avoid piecemeal examination. See MPEP § 707.07(g) (“Piecemeal examination should be avoided as much as possible. The examiner ordinarily should reject each claim on all valid grounds available . . . .”).

II.   PRIOR ART REJECTION OF CLAIM REJECTED AS INDEFINITE

All words in a claim must be considered in judging the patentability of a claim against the prior art. In re Wilson, 424 F.2d 1382, 165 USPQ 494 (CCPA 1970). The fact that terms may be indefinite does not make the claim obvious over the prior art. When the terms of a claim are considered to be indefinite, at least two approaches to the examination of an indefinite claim relative to the prior art are possible.

First, where the degree of uncertainty is not great, and where the claim is subject to more than one interpretation and at least one interpretation would render the claim unpatentable over the prior art, an appropriate course of action would be for the examiner to enter two rejections: (A) a rejection based on indefiniteness under 35 U.S.C. 112(b) or pre-AIA 35 U.S.C. 112, second paragraph; and (B) a rejection over the prior art based on the interpretation of the claims which renders the prior art applicable. See, e.g., Ex parte Ionescu, 222 USPQ 537 (Bd. App. 1984). When making a rejection over prior art in these circumstances, it is important for the examiner to point out how the claim is being interpreted. Second, where there is a great deal of confusion and uncertainty as to the proper interpretation of the limitations of a claim, it would not be proper to reject such a claim on the basis of prior art. As stated in In reSteele, 305 F.2d 859, 134 USPQ 292 (CCPA 1962), a rejection under 35 U.S.C. 103 should not be based on considerable speculation about the meaning of terms employed in a claim or assumptions that must be made as to the scope of the claims.

The first approach is recommended from an examination standpoint because it avoids piecemeal examination in the event that the examiner’s 35 U.S.C. 112, second paragraph rejection is not affirmed, and may give applicant a better appreciation for relevant prior art if the claims are redrafted to avoid the 35 U.S.C. 112(b) or pre-AIA 35 U.S.C. 112, second paragraph rejection.

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