MPEP § 2143.03 — All Claim Limitations Must Be Considered (Annotated Rules)

§2143.03 All Claim Limitations Must Be Considered

USPTO MPEP version: BlueIron's Update: 2026-01-10

This page consolidates and annotates all enforceable requirements under MPEP § 2143.03, including statutory authority, regulatory rules, examiner guidance, and practice notes. It is provided as guidance, with links to the ground truth sources. This is information only, it is not legal advice.

All Claim Limitations Must Be Considered

This section addresses All Claim Limitations Must Be Considered. Primary authority: 35 U.S.C. 103, 35 U.S.C. 112(b), and 35 U.S.C. 112. Contains: 2 prohibitions, 3 guidance statements, and 2 other statements.

Key Rules

Topic

Appeal to Federal Circuit

3 rules
StatutoryInformativeAlways
[mpep-2143-03-9c25ca4710913d4ff3cdf536]
Both Rejections Required for Indefinite Claims
Note:
When a claim is indefinite, both indefiniteness and prior art rejections must be made to avoid piecemeal appellate review.

A claim limitation which is considered indefinite cannot be disregarded. If a claim is subject to more than one interpretation, at least one of which would render the claim unpatentable over the prior art, the examiner should reject the claim as indefinite under 35 U.S.C. 112(b) or pre-AIA 35 U.S.C. 112, second paragraph (see MPEP § 2175) and should reject the claim over the prior art based on the interpretation of the claim that renders the prior art applicable. Ex parte Ionescu, 222 USPQ 537 (Bd. Pat. App. & Inter. 1984) (Claims on appeal were rejected on indefiniteness grounds only; the rejection was reversed and the case remanded to the examiner for consideration of pertinent prior art.). Making both rejections, when appropriate, avoids piecemeal appellate review. See Ionescu, 222 USPQ at 540 n.9 (citing CCPA and Federal Circuit cases.). See also In re Wilson, 424 F.2d 1382, 165 USPQ 494 (CCPA 1970) (The Board erred because it ignored claim language that it considered to be indefinite, and reached a conclusion that the claim would have been obvious based only on the rest of the claim.). However, an examiner should not simply speculate about the meaning of the claim language and then enter an obviousness rejection in view of that speculative interpretation. In re Steele, 305 F.2d 859,134 USPQ 292 (CCPA 1962) (The “considerable speculation” by the examiner and the Board as to the scope of the claims did not provide a proper basis for an obviousness rejection.). A claim should not be rejected over prior art just because it is indefinite. Ionescu, 222 USPQ at 540 (citing Steele). Although a claim that is indefinite because it is susceptible to more than one interpretation may be rejected over prior art, an examiner should not base a prior art rejection on a claim interpretation that is not reasonable; see MPEP § 2111 regarding proper claim interpretation.

Jump to MPEP SourceAppeal to Federal CircuitAlternative Limitations (MPEP 2173.05(h))Lack of Antecedent Basis (MPEP 2173.05(e))
StatutoryRecommendedAlways
[mpep-2143-03-10ba3e50fe73a9ddb0fdb5d1]
Claim Language Must Not Be Speculatively Interpreted for Obviousness Rejection
Note:
An examiner should not speculate on claim language to support an obviousness rejection; instead, reject the claim as indefinite if it is susceptible to multiple interpretations.

A claim limitation which is considered indefinite cannot be disregarded. If a claim is subject to more than one interpretation, at least one of which would render the claim unpatentable over the prior art, the examiner should reject the claim as indefinite under 35 U.S.C. 112(b) or pre-AIA 35 U.S.C. 112, second paragraph (see MPEP § 2175) and should reject the claim over the prior art based on the interpretation of the claim that renders the prior art applicable. Ex parte Ionescu, 222 USPQ 537 (Bd. Pat. App. & Inter. 1984) (Claims on appeal were rejected on indefiniteness grounds only; the rejection was reversed and the case remanded to the examiner for consideration of pertinent prior art.). Making both rejections, when appropriate, avoids piecemeal appellate review. See Ionescu, 222 USPQ at 540 n.9 (citing CCPA and Federal Circuit cases.). See also In re Wilson, 424 F.2d 1382, 165 USPQ 494 (CCPA 1970) (The Board erred because it ignored claim language that it considered to be indefinite, and reached a conclusion that the claim would have been obvious based only on the rest of the claim.). However, an examiner should not simply speculate about the meaning of the claim language and then enter an obviousness rejection in view of that speculative interpretation. In re Steele, 305 F.2d 859,134 USPQ 292 (CCPA 1962) (The “considerable speculation” by the examiner and the Board as to the scope of the claims did not provide a proper basis for an obviousness rejection.). A claim should not be rejected over prior art just because it is indefinite. Ionescu, 222 USPQ at 540 (citing Steele). Although a claim that is indefinite because it is susceptible to more than one interpretation may be rejected over prior art, an examiner should not base a prior art rejection on a claim interpretation that is not reasonable; see MPEP § 2111 regarding proper claim interpretation.

Jump to MPEP SourceAppeal to Federal CircuitLack of Antecedent Basis (MPEP 2173.05(e))Relative Terminology (MPEP 2173.05(b))
StatutoryInformativeAlways
[mpep-2143-03-a8d3284ce101fc5ca57e51d4]
Claim Limitation Must Be Considered Before Prior Art Rejection
Note:
A claim limitation that is indefinite cannot be disregarded; it must be considered before a rejection over prior art can be made.

A claim limitation which is considered indefinite cannot be disregarded. If a claim is subject to more than one interpretation, at least one of which would render the claim unpatentable over the prior art, the examiner should reject the claim as indefinite under 35 U.S.C. 112(b) or pre-AIA 35 U.S.C. 112, second paragraph (see MPEP § 2175) and should reject the claim over the prior art based on the interpretation of the claim that renders the prior art applicable. Ex parte Ionescu, 222 USPQ 537 (Bd. Pat. App. & Inter. 1984) (Claims on appeal were rejected on indefiniteness grounds only; the rejection was reversed and the case remanded to the examiner for consideration of pertinent prior art.). Making both rejections, when appropriate, avoids piecemeal appellate review. See Ionescu, 222 USPQ at 540 n.9 (citing CCPA and Federal Circuit cases.). See also In re Wilson, 424 F.2d 1382, 165 USPQ 494 (CCPA 1970) (The Board erred because it ignored claim language that it considered to be indefinite, and reached a conclusion that the claim would have been obvious based only on the rest of the claim.). However, an examiner should not simply speculate about the meaning of the claim language and then enter an obviousness rejection in view of that speculative interpretation. In re Steele, 305 F.2d 859,134 USPQ 292 (CCPA 1962) (The “considerable speculation” by the examiner and the Board as to the scope of the claims did not provide a proper basis for an obviousness rejection.). A claim should not be rejected over prior art just because it is indefinite. Ionescu, 222 USPQ at 540 (citing Steele). Although a claim that is indefinite because it is susceptible to more than one interpretation may be rejected over prior art, an examiner should not base a prior art rejection on a claim interpretation that is not reasonable; see MPEP § 2111 regarding proper claim interpretation.

Jump to MPEP SourceAppeal to Federal CircuitAlternative Limitations (MPEP 2173.05(h))Lack of Antecedent Basis (MPEP 2173.05(e))
Topic

35 U.S.C. 112(b) – Definiteness (MPEP 2171-2173)

2 rules
StatutoryProhibitedAlways
[mpep-2143-03-18f7df72b22f469478d304a1]
Claim Limitation Indefiniteness Must Not Be Ignored
Note:
A claim with indefinite limitations must not be disregarded; it should be rejected as indefinite and evaluated based on the most reasonable interpretation that could render it unpatentable over prior art.

A claim limitation which is considered indefinite cannot be disregarded. If a claim is subject to more than one interpretation, at least one of which would render the claim unpatentable over the prior art, the examiner should reject the claim as indefinite under 35 U.S.C. 112(b) or pre-AIA 35 U.S.C. 112, second paragraph (see MPEP § 2175) and should reject the claim over the prior art based on the interpretation of the claim that renders the prior art applicable. Ex parte Ionescu, 222 USPQ 537 (Bd. Pat. App. & Inter. 1984) (Claims on appeal were rejected on indefiniteness grounds only; the rejection was reversed and the case remanded to the examiner for consideration of pertinent prior art.). Making both rejections, when appropriate, avoids piecemeal appellate review. See Ionescu, 222 USPQ at 540 n.9 (citing CCPA and Federal Circuit cases.). See also In re Wilson, 424 F.2d 1382, 165 USPQ 494 (CCPA 1970) (The Board erred because it ignored claim language that it considered to be indefinite, and reached a conclusion that the claim would have been obvious based only on the rest of the claim.). However, an examiner should not simply speculate about the meaning of the claim language and then enter an obviousness rejection in view of that speculative interpretation. In re Steele, 305 F.2d 859,134 USPQ 292 (CCPA 1962) (The “considerable speculation” by the examiner and the Board as to the scope of the claims did not provide a proper basis for an obviousness rejection.). A claim should not be rejected over prior art just because it is indefinite. Ionescu, 222 USPQ at 540 (citing Steele). Although a claim that is indefinite because it is susceptible to more than one interpretation may be rejected over prior art, an examiner should not base a prior art rejection on a claim interpretation that is not reasonable; see MPEP § 2111 regarding proper claim interpretation.

Jump to MPEP Source35 U.S.C. 112(b) – Definiteness (MPEP 2171-2173)Appeal to Federal CircuitAlternative Limitations (MPEP 2173.05(h))
StatutoryRecommendedAlways
[mpep-2143-03-15c015ad477957909f400271]
Indefinite Claims Not Rejected Over Prior Art
Note:
A claim should not be rejected based on prior art if it is indefinite and subject to multiple interpretations.

A claim limitation which is considered indefinite cannot be disregarded. If a claim is subject to more than one interpretation, at least one of which would render the claim unpatentable over the prior art, the examiner should reject the claim as indefinite under 35 U.S.C. 112(b) or pre-AIA 35 U.S.C. 112, second paragraph (see MPEP § 2175) and should reject the claim over the prior art based on the interpretation of the claim that renders the prior art applicable. Ex parte Ionescu, 222 USPQ 537 (Bd. Pat. App. & Inter. 1984) (Claims on appeal were rejected on indefiniteness grounds only; the rejection was reversed and the case remanded to the examiner for consideration of pertinent prior art.). Making both rejections, when appropriate, avoids piecemeal appellate review. See Ionescu, 222 USPQ at 540 n.9 (citing CCPA and Federal Circuit cases.). See also In re Wilson, 424 F.2d 1382, 165 USPQ 494 (CCPA 1970) (The Board erred because it ignored claim language that it considered to be indefinite, and reached a conclusion that the claim would have been obvious based only on the rest of the claim.). However, an examiner should not simply speculate about the meaning of the claim language and then enter an obviousness rejection in view of that speculative interpretation. In re Steele, 305 F.2d 859,134 USPQ 292 (CCPA 1962) (The “considerable speculation” by the examiner and the Board as to the scope of the claims did not provide a proper basis for an obviousness rejection.). A claim should not be rejected over prior art just because it is indefinite. Ionescu, 222 USPQ at 540 (citing Steele). Although a claim that is indefinite because it is susceptible to more than one interpretation may be rejected over prior art, an examiner should not base a prior art rejection on a claim interpretation that is not reasonable; see MPEP § 2111 regarding proper claim interpretation.

Jump to MPEP Source35 U.S.C. 112(b) – Definiteness (MPEP 2171-2173)Appeal to Federal CircuitAlternative Limitations (MPEP 2173.05(h))
Topic

35 U.S.C. 103 – Obviousness

1 rules
StatutoryProhibitedAlways
[mpep-2143-03-c5c527cfdb5d0c4f01befb1b]
Dependent Claims Must Be Nonobvious If Independent Claim Is
Note:
If an independent claim is nonobvious under 35 U.S.C. 103, any dependent claims must also be nonobvious unless the dependent claim is not properly dependent or its effective filing date is later than the independent claim's.

If an independent claim is nonobvious under 35 U.S.C. 103, then any claim depending therefrom is nonobvious. In re Fine, 837 F.2d 1071, 5 USPQ2d 1596 (Fed. Cir. 1988). However, this conclusion of the Fine court may not apply if a claim is not properly dependent or if the effective filing date of a dependent claim is later than the effective filing date of an independent claim from which the dependent claim depends. See MPEP § 608.01(n) for a discussion of dependent claims and MPEP § 2133.01 and § 2152.01 for a discussion of effective filing date of a claimed invention determined on a claim-by-claim basis.

Topic

Alternative Limitations (MPEP 2173.05(h))

1 rules
StatutoryRecommendedAlways
[mpep-2143-03-c57dbce4af1f0e8126892c76]
Indefinite Claim Rejection and Prior Art Consideration
Note:
If a claim can be interpreted in multiple ways, at least one of which makes it unpatentable over prior art, the examiner must reject the claim as indefinite and consider prior art based on that interpretation.

A claim limitation which is considered indefinite cannot be disregarded. If a claim is subject to more than one interpretation, at least one of which would render the claim unpatentable over the prior art, the examiner should reject the claim as indefinite under 35 U.S.C. 112(b) or pre-AIA 35 U.S.C. 112, second paragraph (see MPEP § 2175) and should reject the claim over the prior art based on the interpretation of the claim that renders the prior art applicable. Ex parte Ionescu, 222 USPQ 537 (Bd. Pat. App. & Inter. 1984) (Claims on appeal were rejected on indefiniteness grounds only; the rejection was reversed and the case remanded to the examiner for consideration of pertinent prior art.). Making both rejections, when appropriate, avoids piecemeal appellate review. See Ionescu, 222 USPQ at 540 n.9 (citing CCPA and Federal Circuit cases.). See also In re Wilson, 424 F.2d 1382, 165 USPQ 494 (CCPA 1970) (The Board erred because it ignored claim language that it considered to be indefinite, and reached a conclusion that the claim would have been obvious based only on the rest of the claim.). However, an examiner should not simply speculate about the meaning of the claim language and then enter an obviousness rejection in view of that speculative interpretation. In re Steele, 305 F.2d 859,134 USPQ 292 (CCPA 1962) (The “considerable speculation” by the examiner and the Board as to the scope of the claims did not provide a proper basis for an obviousness rejection.). A claim should not be rejected over prior art just because it is indefinite. Ionescu, 222 USPQ at 540 (citing Steele). Although a claim that is indefinite because it is susceptible to more than one interpretation may be rejected over prior art, an examiner should not base a prior art rejection on a claim interpretation that is not reasonable; see MPEP § 2111 regarding proper claim interpretation.

Jump to MPEP SourceAlternative Limitations (MPEP 2173.05(h))Lack of Antecedent Basis (MPEP 2173.05(e))Numerical Ranges and Amounts (MPEP 2173.05(c))
Topic

Interpreting Claims (MPEP 2173.01)

1 rules
StatutoryRecommendedAlways
[mpep-2143-03-5b034d9f294c337f048e7f5c]
Proper Claim Interpretation for Prior Art Rejection
Note:
An examiner must not base a prior art rejection on an unreasonable claim interpretation; reject claims as indefinite if susceptible to multiple interpretations and then consider pertinent prior art.

A claim limitation which is considered indefinite cannot be disregarded. If a claim is subject to more than one interpretation, at least one of which would render the claim unpatentable over the prior art, the examiner should reject the claim as indefinite under 35 U.S.C. 112(b) or pre-AIA 35 U.S.C. 112, second paragraph (see MPEP § 2175) and should reject the claim over the prior art based on the interpretation of the claim that renders the prior art applicable. Ex parte Ionescu, 222 USPQ 537 (Bd. Pat. App. & Inter. 1984) (Claims on appeal were rejected on indefiniteness grounds only; the rejection was reversed and the case remanded to the examiner for consideration of pertinent prior art.). Making both rejections, when appropriate, avoids piecemeal appellate review. See Ionescu, 222 USPQ at 540 n.9 (citing CCPA and Federal Circuit cases.). See also In re Wilson, 424 F.2d 1382, 165 USPQ 494 (CCPA 1970) (The Board erred because it ignored claim language that it considered to be indefinite, and reached a conclusion that the claim would have been obvious based only on the rest of the claim.). However, an examiner should not simply speculate about the meaning of the claim language and then enter an obviousness rejection in view of that speculative interpretation. In re Steele, 305 F.2d 859,134 USPQ 292 (CCPA 1962) (The “considerable speculation” by the examiner and the Board as to the scope of the claims did not provide a proper basis for an obviousness rejection.). A claim should not be rejected over prior art just because it is indefinite. Ionescu, 222 USPQ at 540 (citing Steele). Although a claim that is indefinite because it is susceptible to more than one interpretation may be rejected over prior art, an examiner should not base a prior art rejection on a claim interpretation that is not reasonable; see MPEP § 2111 regarding proper claim interpretation.

Jump to MPEP SourceInterpreting Claims (MPEP 2173.01)35 U.S.C. 112(b) – Definiteness (MPEP 2171-2173)Appeal to Federal Circuit
Topic

Claims Directed To

1 rules
StatutoryRequiredAlways
[mpep-2143-03-17a46d275f77fa0472564968]
All Claim Limitations Must Be Considered When Evaluating Obviousness
Note:
When assessing claims for obviousness under 35 U.S.C. 103, all claim limitations must be evaluated, even those not originally supported in the specification.

When evaluating claims for obviousness under 35 U.S.C. 103, all the limitations of the claims must be considered and given weight, including limitations which do not find support in the specification as originally filed (i.e., new matter). Ex parte Grasselli, 231 USPQ 393 (Bd. App. 1983) aff’d mem. 738 F.2d 453 (Fed. Cir. 1984) (Claim to a catalyst expressly excluded the presence of sulfur, halogen, uranium, and a combination of vanadium and phosphorous. Although the negative limitations excluding these elements did not appear in the specification as filed, it was error to disregard these limitations when determining whether the claimed invention would have been obvious in view of the prior art.). “All words in a claim must be considered in judging the patentability of that claim against the prior art.” In re Miller, 441 F.2d 689, 694, 169 USPQ 597, 600 (CCPA 1971) (quoting In re Wilson, 424 F.2d 1382, 1385, 165 USPQ 494, 496 (CCPA 1970)).

Jump to MPEP SourceClaims Directed ToRequired Claim ContentPrior Art in Reissue
Topic

Claim Subject Matter

1 rules
StatutoryInformativeAlways
[mpep-2143-03-9695aa991726b5c0bdebdf0c]
Negative Limitations Must Be Considered When Determining Obviousness
Note:
All claim limitations, including negative ones not originally in the specification, must be considered when assessing obviousness over prior art.

When evaluating claims for obviousness under 35 U.S.C. 103, all the limitations of the claims must be considered and given weight, including limitations which do not find support in the specification as originally filed (i.e., new matter). Ex parte Grasselli, 231 USPQ 393 (Bd. App. 1983) aff’d mem. 738 F.2d 453 (Fed. Cir. 1984) (Claim to a catalyst expressly excluded the presence of sulfur, halogen, uranium, and a combination of vanadium and phosphorous. Although the negative limitations excluding these elements did not appear in the specification as filed, it was error to disregard these limitations when determining whether the claimed invention would have been obvious in view of the prior art.). “All words in a claim must be considered in judging the patentability of that claim against the prior art.” In re Miller, 441 F.2d 689, 694, 169 USPQ 597, 600 (CCPA 1971) (quoting In re Wilson, 424 F.2d 1382, 1385, 165 USPQ 494, 496 (CCPA 1970)).

Jump to MPEP SourceClaim Subject MatterPrior Art in Reissue
Topic

Required Claim Content

1 rules
StatutoryRequiredAlways
[mpep-2143-03-076ae8c8059639fba6b5fda8]
All Claim Limitations Must Be Considered
Note:
When evaluating claims for patentability, all limitations must be considered against the prior art, including those not originally supported in the specification.

When evaluating claims for obviousness under 35 U.S.C. 103, all the limitations of the claims must be considered and given weight, including limitations which do not find support in the specification as originally filed (i.e., new matter). Ex parte Grasselli, 231 USPQ 393 (Bd. App. 1983) aff’d mem. 738 F.2d 453 (Fed. Cir. 1984) (Claim to a catalyst expressly excluded the presence of sulfur, halogen, uranium, and a combination of vanadium and phosphorous. Although the negative limitations excluding these elements did not appear in the specification as filed, it was error to disregard these limitations when determining whether the claimed invention would have been obvious in view of the prior art.). “All words in a claim must be considered in judging the patentability of that claim against the prior art.” In re Miller, 441 F.2d 689, 694, 169 USPQ 597, 600 (CCPA 1971) (quoting In re Wilson, 424 F.2d 1382, 1385, 165 USPQ 494, 496 (CCPA 1970)).

Jump to MPEP SourceRequired Claim ContentPrior Art in Reissue

Citations

Primary topicCitation
35 U.S.C. 103 – Obviousness
Claim Subject Matter
Claims Directed To
Required Claim Content
35 U.S.C. § 103
35 U.S.C. 112(b) – Definiteness (MPEP 2171-2173)
Alternative Limitations (MPEP 2173.05(h))
Appeal to Federal Circuit
Interpreting Claims (MPEP 2173.01)
35 U.S.C. § 112
35 U.S.C. 112(b) – Definiteness (MPEP 2171-2173)
Alternative Limitations (MPEP 2173.05(h))
Appeal to Federal Circuit
Interpreting Claims (MPEP 2173.01)
35 U.S.C. § 112(b)
35 U.S.C. 103 – Obviousness37 CFR § 2152.01
35 U.S.C. 112(b) – Definiteness (MPEP 2171-2173)
Alternative Limitations (MPEP 2173.05(h))
Appeal to Federal Circuit
Interpreting Claims (MPEP 2173.01)
MPEP § 2111
MPEP § 2111.02
MPEP § 2111.04
MPEP § 2111.05
35 U.S.C. 103 – ObviousnessMPEP § 2133.01
35 U.S.C. 112(b) – Definiteness (MPEP 2171-2173)
Alternative Limitations (MPEP 2173.05(h))
Appeal to Federal Circuit
Interpreting Claims (MPEP 2173.01)
MPEP § 2175
MPEP § 2181
35 U.S.C. 103 – ObviousnessMPEP § 608.01(n)
Griffin v. Bertina, 285 F.3d 1029, 1034, 62 USPQ2d 1431 (Fed. Cir. 2002)
35 U.S.C. 103 – ObviousnessIn re Fine, 837 F.2d 1071, 5 USPQ2d 1596 (Fed. Cir. 1988)
Claim Subject Matter
Claims Directed To
Required Claim Content
In re Miller, 441 F.2d 689, 694, 169 USPQ 597, 600 (CCPA 1971)
35 U.S.C. 112(b) – Definiteness (MPEP 2171-2173)
Alternative Limitations (MPEP 2173.05(h))
Appeal to Federal Circuit
Interpreting Claims (MPEP 2173.01)
In re Steele, 305 F.2d 859,134 USPQ 292 (CCPA 1962)
35 U.S.C. 112(b) – Definiteness (MPEP 2171-2173)
Alternative Limitations (MPEP 2173.05(h))
Appeal to Federal Circuit
Claim Subject Matter
Claims Directed To
Interpreting Claims (MPEP 2173.01)
Required Claim Content
In re Wilson, 424 F.2d 1382, 1385, 165 USPQ 494, 496 (CCPA 1970)

Source Text from USPTO’s MPEP

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BlueIron Last Updated: 2026-01-10