One Claim, Many Paths: Multiple Dependent Claims in the United States, Europe, China, Korea, and Japan

Executive summary. A multiple dependent claim can compress several claim combinations into one numbered claim. That economy is attractive in offices that charge by numbered claim, but it is less attractive in the United States, where fee calculations expand the claim into its alternative dependencies and a separate surcharge applies. The most consequential difference is nested dependency: PCT Rule 6.4 and the rules of the United States, China, Korea, and Japan bar a multiple dependent claim from serving as the basis for another multiple dependent claim, while EPO practice has no comparable categorical prohibition and instead polices the structure principally through clarity. The practical lesson is that multiple dependency is not merely a drafting shortcut; it is claim architecture that must be designed for fees, examination, amendment, and national-phase portability.

1. The Small Drafting Choice With Portfolio-Wide Consequences

 

Dependent claims are often treated as the quiet infrastructure of a patent application. They preserve narrower fallback positions, map commercial embodiments, and give an examiner routes to allowance. Multiple dependent claims perform the same work more compactly: one numbered claim can place the same added limitation onto two or more earlier claims.

Dependency is therefore a form of claim architecture. It determines which limitations travel together, which combinations remain visible as separate fallback positions, and how readily a claim set can be reorganized when an office applies a different formal rule. The printed number of claims may be small even though the set contains many legally distinct paths. Conversely, a longer list of single dependent claims may be easier to prosecute, audit, and amend because each intended combination is stated expressly.

That compactness, however, is not portable in the same way everywhere. An ordinary alternative-only multiple dependent claim may trigger a U.S. fee or an EPO clarity review. Cumulative multiple references are improper in the United States, China, and Korea; nested alternative dependency is also barred in those offices and can supply a reason for refusal in Japan for governed filings. The differences matter most in PCT applications, where a tree that conflicts with Rule 6.4 can impair the international search and require later restructuring without adding subject matter.

The issue is therefore not merely whether an office permits a multiple dependent claim. Counsel must also ask four additional questions: Must the references be alternative? May a multiple dependent claim depend on another multiple dependent claim? How are the alternatives counted for fees? And how will the office examine or refuse an improper structure?

This article compares five major PCT destinations because they illustrate materially different approaches to multiple-dependent form, nested dependency, and fees. It addresses drafting, international- and national-phase amendment, prosecution, and fee treatment, not claim construction, validity, infringement, or other post-grant questions. Authorities and fees are current through August 2026; official sources are used, with English-language texts where available.

Among the five offices examined, the procedurally most portable claim tree is not necessarily the economically optimal one. Counsel should therefore use PCT Rule 6.4 as a portability baseline, preserve important combinations in the disclosure and a dependency map, and selectively localize claim structure when national fee and examination rules justify it.

2. Definitions and the PCT Baseline

 

A simple dependent claim refers to one earlier claim. An ordinary multiple dependent claim refers to two or more earlier claims and applies its added limitation separately to each referenced claim. A multi-multi claim is a multiple dependent claim that depends, directly or through an intervening chain, on another multiple dependent claim.

Claim 1. A device comprising element A.Claim 2. The device of claim 1, further comprising element B.Claim 3. The device of claim 1, further comprising element C.Claim 4. The device of claim 2 or 3, further comprising element D.Claim 5. The device of claim 4, further comprising element E.Claim 6. The device of claim 3 or 5, further comprising element F.

Claim 4 is an ordinary multiple dependent claim, creating paths 4/2 and 4/3. Claim 5 is a single dependent claim from claim 4 and carries both paths forward. Claim 6 is a multi-multi claim because its claim-5 branch ultimately depends on claim 4, another multiple dependent claim. This direct/indirect distinction, not the mere presence of more than one reference, is the fault line in several jurisdictions.

The PCT supplies a useful common baseline. Rule 6.4(a) requires references to multiple claims to be in the alternative and bars a multiple dependent claim from serving as the basis for another. Rule 6.4(b) explains how the referenced limitations are incorporated; Rule 6.4(c) addresses grouping claims that refer back to preceding claims. Noncompliance may affect the international search when the International Searching Authority's national law does not permit the drafting form and meaningful search is impaired. Noncompliance has no effect in a designated State if the form actually used satisfies that State's national law. PCT Rule 6.4; PCT art. 17(2)(a)(ii), (b); PCT International Search and Preliminary Examination Guidelines para. 9.41 (in force Jan. 1, 2026).

Printed claims and substantive combinations

 

The distinction between a numbered claim and a claim combination is essential. Claim 4 is one printed claim but represents paths 4/2 and 4/3; claim 5 carries both paths through claim 4. Claim 6 adds a separate branch and, in jurisdictions that bar multi-multi dependency, is improper because its claim-5 branch reaches claim 4. Offices may count and examine those paths differently, but each must be tracked for prior-art analysis, amendment, and claim-status tracking.

This explains why multiple dependency can be economical without being simple. It reduces the visible claim count, yet it can increase the number of combinations that counsel and the examiner must track. A useful drafting record therefore identifies both the printed claim number and every direct and indirect dependency path represented by that number.

3. Formal-Rule and Fee Snapshot

Office	Ordinary MDC form	Multi-multi	Fee consequence
United States	Yes; alternative only; earlier claims	Prohibited	Special MDC fee; alternatives counted for claim fees
EPO	Yes; broad references if clear	No categorical ban	Numbered-claim thresholds; no MDC multiplier stated
China	Yes; alternative only; earlier claims	Prohibited	One numbered claim; extra filing fee above ten claims
Korea	Yes; alternative only; earlier claims	Prohibited, including specified indirect structures	One claim for examination-fee calculation
Japan	Ordinary MDC permitted	Prohibited since Apr. 2022	Claim-number-based fees; no U.S.-style permutation multiplier

Primary form authorities: 35 U.S.C. § 112(e); EPC Rule 43(4); China Implementing Rules art. 25; Korean Enforcement Decree art. 5(5)-(7); and JPO multi-multi guidance. Fee authorities are collected below under Selected Authorities and Data Sources.

4. United States: Permitted, but Often Economically Unattractive

 

Form and legal effect

 

U.S. law permits a claim to refer to more than one earlier claim, but only in the alternative. A multiple dependent claim may not serve as the basis for another multiple dependent claim. Thus, "the device of claim 2 or 3" may be proper, while "the device of claim 2 and 3" is ordinarily improper, as is a multiple dependent claim that includes another multiple dependent claim among its alternatives. 35 U.S.C. § 112(e); 37 C.F.R. § 1.75(c); MPEP § 608.01(n)(I).

The alternatives are not cumulative. Each is construed separately with the limitations of the particular referenced claim. Examination likewise proceeds by embodiment or permutation, and different alternatives may receive different treatment in restriction or on the merits. MPEP § 608.01(n)(I)(C).

Direct and indirect dependency

 

The U.S. prohibition extends beyond an obvious direct reference. A single dependent claim may depend on a proper multiple dependent claim, but a later multiple dependent claim cannot refer to that descendant if doing so indirectly uses the earlier multiple dependent claim as a base. The dependency tree must therefore be reviewed through every intervening claim, not merely by checking the claims named in the final sentence. MPEP § 608.01(n)(I).

That distinction also affects office treatment. A proper multiple dependent claim is examined as the equivalent of its separate alternatives. An improper multiple dependent claim is normally objected to under 37 C.F.R. § 1.75(c) and ordinarily is not further treated on the merits until corrected. MPEP § 608.01(n)(I)(B), form para. 7.45. Detecting the problem before filing avoids building a prosecution strategy around a branch that the Office will not examine in its submitted form.

Fees drive drafting behavior

 

The U.S. fee system removes much of the apparent numerical economy. A proper multiple dependent claim is counted, for fee purposes, as the number of claims to which it directly refers. A claim depending directly or indirectly from that proper multiple dependent claim is counted using the same multiplier. For an original nonprovisional application filed under 35 U.S.C. § 111(a), at least one proper multiple dependent claim triggers the fee under 37 C.F.R. § 1.16(j); a national-stage application under § 371 instead implicates 37 C.F.R. § 1.492(f). MPEP § 608.01(n)(I)(G)(2)(a).

As a practical result, collapsing several single dependent claims into one multiple dependent claim may save claim numbers without saving fees. It can instead make fee calculations and prosecution tracking more complicated. U.S. counsel may therefore rationally favor explicit single dependencies, particularly when the desired combinations are few and strategically selected.

A worked counting example

 

Using claims 1-5 above, claims 1-3 count once each. Claim 4 counts as two for U.S. fee purposes because it directly refers to claims 2 and 3; claim 5 also counts as two because it depends from claim 4. Thus, five printed claims count as seven claims, and the separate multiple-dependent-claim fee applies. Claim 6 is excluded from this arithmetic because it is an improper multiple dependent claim and must be corrected before merits treatment. MPEP § 608.01(n)(I)(G)(2)(c)(i), Claims 4 and 5.

The comparison with explicit single dependencies is not purely mathematical. Separate claims make the intended combinations immediately visible, simplify claim-status charts, and permit counsel to cancel or amend one path without rewriting the others. A multiple dependent format is most useful when those administrative costs are outweighed by a genuine drafting or portfolio advantage.

Limited U.S. administrative evidence

 

USPTO paperwork-burden estimates are consistent with fee-triggering proper multiple dependent claims being uncommon in current U.S. practice. In a 2024 Paperwork Reduction Act notice, the USPTO projected 1,270 annual multiple-dependent-claim fee responses. The same notice projected 366,005 annual application responses across the utility and plant application categories associated with those fee rows (items 1, 2, 4-6, and 9), yielding an author-calculated ratio of approximately 0.35%. Agency Information Collection Activities; Submission to the Office of Management and Budget (OMB) for Review and Approval; Comment Request; Initial Patent Applications, 89 Fed. Reg. 1,557, 1,560-61 (Jan. 10, 2024). A 2025 notice projected 1,016 national-stage multiple-dependent-claim fee responses and 108,371 basic national-stage fee responses, yielding an author-calculated ratio of approximately 0.94%. Agency Information Collection Activities; Submission to the Office of Management and Budget for Review and Approval; Comment Request; Patent Cooperation Treaty, 90 Fed. Reg. 26,555, 26,558 (June 23, 2025).

These are ratios of projected administrative fee events, not observed incidence rates or matched application cohorts. Moreover, the separate fee applies if an application contains at least one proper multiple dependent claim, while an application containing only improper multiple dependent claims does not trigger it. MPEP § 607; MPEP § 608.01(n)(I)(G)(2)(b). The estimates therefore support only the narrower inference that fee-triggering proper multiple dependent claims are uncommon; they do not measure all multiple-dependent-claim drafting or permit cross-office frequency comparisons.

5. EPO: Broad Structural Flexibility, Limited by Clarity

 

Form

 

Rule 43(4) EPC defines dependent claims by reference to another claim, and the Guidelines expressly permit a dependent claim to refer to one or more independent claims, one or more dependent claims, or both. EPC Rule 43(4); EPO Guidelines for Examination pt. F, ch. IV, § 3.4 (Apr. 2026).

Unlike the PCT rule and the rules in the United States, China, Korea, and Japan, the EPC framework does not categorically bar a multiple dependent claim from referring to another multiple dependent claim or require alternative-only references. Cross-category references and nested dependency are not objectionable on those grounds alone, but clarity, conciseness, support, unity, claim-category, and other EPC requirements still apply. EPO Guidelines for Examination pt. F, ch. IV, §§ 3.4, 3.8 (Apr. 2026).

That flexibility is not a license to build an unreadable dependency lattice. A claim may be formally possible yet strategically poor if an examiner cannot determine which limitations are present in a given branch or if the structure creates uncertainty about category, antecedent basis, or amendment options.

Clarity and amendment discipline

 

At the EPO, the central question is not whether the tree fits a prescribed dependency pattern, but whether the reader can determine the subject matter of each branch. Article 84 EPC requires the claims to be clear, concise, and supported by the description. A multi-multi structure that mixes claim categories, creates incompatible alternatives, or leaves incorporated features uncertain can therefore attract an objection even though cross-category or nested dependency is not objectionable by itself.

Amendment support is a separate concern. Flattening a dense dependency tree may require counsel to state expressly a combination that was previously conveyed only through several references. The application as filed should make the important combinations directly and unambiguously derivable so that later amendments comply with Article 123(2) EPC. EPO Guidelines for Examination pt. H, ch. IV, § 2.2 (Apr. 2026). Fee-efficient drafting should not come at the expense of a reliable basis for amendment.

Fees

 

EPO claims fees are assessed by numbered claim: a fee is due for each claim over 15, with a higher fee amount for each claim over 50. Because the schedule contains no alternative-path multiplier, an ordinary multiple dependent claim occupies one claim number for these thresholds. EPO Guidelines for Examination pt. A, ch. III, § 9 (Apr. 2026). Multiple dependency can therefore compress fallback combinations for EPO fee purposes.

6. China: Alternative References and a Flat Claim Count

 

Form

 

Article 25 requires a dependent claim to identify the referenced claim number and subject title, followed by the additional technical features. A dependent claim may refer only to earlier claims. A claim referring to two or more claims must do so in the alternative, and such a multiple dependent claim may not serve as the basis for another multiple dependent claim. Implementing Regulations of the Patent Law of the People's Republic of China art. 25 (amended Dec. 11, 2023; effective Jan. 20, 2024).

A U.S.- or PCT-compliant ordinary multiple dependent claim will therefore often fit Chinese formal practice, provided the reference wording and subject designation are adapted correctly. A claim tree containing cumulative or multi-multi dependency already conflicts with PCT Rule 6.4 and should normally be flattened before PCT filing; if it remains in the international application, it must be corrected for Chinese practice.

Flattening without losing coverage

 

Flattening does not necessarily require copying every theoretical permutation into a separate claim. Counsel can first identify the combinations that correspond to commercial embodiments, likely design-arounds, and meaningful patentability fallbacks, and then express those paths through proper single or ordinary multiple dependency. The exercise should be completed against the Chinese claim text, because translation can change whether a reference reads as alternative or cumulative. China Implementing Rules art. 25.

Fees and strategy

 

CNIPA's published fee schedule charges an additional filing fee for each claim exceeding ten. Because the schedule charges by numbered claim and prescribes no multiple-dependent-claim multiplier, an ordinary multiple dependent claim is treated as one numbered claim for this threshold. CNIPA patent fee schedule. That structure can make multiple dependency useful for preserving combinations while controlling the numbered claim count.

7. Korea: Alternative Form, No Multi-Multi Structure

 

Form

 

Article 5(5)-(7) of Korea's Enforcement Decree requires a claim referring to two or more claims to list the references in the alternative and to cite preceding claims. It also bars such a claim from referring to another multiple dependent claim. The February 2026 Guidelines provide detailed examples of direct and indirect noncompliance. Enforcement Decree of the Patent Act art. 5(5)-(7); Ministry of Intellectual Property, Patent Examination Guidelines pt. II, ch. 2, §§ 6.5-6.7, at 163-66 (Feb. 2026).

The Korean guidance is particularly useful because it distinguishes genuine alternative dependency from a claim that cites two components merely to describe a combined invention. The label is less important than the claim's legal operation: examiners assess whether the reference creates alternative dependent embodiments and whether it ultimately relies on another multiple dependency.

The indirect-dependency trap

 

Korean review must follow the entire ancestry of the referring multiple dependent claim. A claim can appear to cite only ordinary parents while still recreating a prohibited structure through an intervening dependent claim. For each multiple dependent claim, expand every referenced path to an independent claim and flag any path containing another multiple dependent claim. The official examples supply useful templates for this graph-based review. Korean Patent Examination Guidelines pt. II, ch. 2, §§ 6.5-6.7.

Fee treatment

 

Korea's filing fee is not assessed per claim. The current schedule, however, includes per-claim components in examination, registration, and annual fees. For examination-fee calculations, the Guidelines state that claims are counted by numbered claim regardless of whether they are independent or dependent, and that even a claim depending on two or more claims is counted as one. There is no U.S.-style permutation multiplier. Korean Patent Examination Guidelines at 87-88; KIPO fee schedule.

8. Japan: Ordinary Multiple Dependency Survives the Multi-Multi Ban

 

The April 2022 change

 

For patent and utility-model applications governed by a filing date on or after April 1, 2022, Japan prohibits multi-multi claims while continuing to permit ordinary multiple dependent claims; for a PCT national-phase application, the relevant date is the international filing date. The restriction reaches claims that depend, directly or indirectly, on another multiple dependent claim, including dependencies across claim categories. JPO, Restriction of Multi-Multi Claims; JPO, Revision of Examination Guidelines and Examination Handbook for Patent and Utility Model in Japan (Apr. 2022).

The procedural consequences make early cleanup important. In patent examination, the JPO generally does not examine the offending multi-multi claim, or claims depending from it, for substantive requirements beyond the ministerial-ordinance defect before issuing a reason for refusal. If the applicant later fixes the dependency and a different substantive rejection emerges, the later action may be final, narrowing amendment freedom. In utility-model practice, an unresolved basic-requirement defect can lead to dismissal.

A PCT national-phase claim set should therefore be screened before Japanese entry and corrected before substantive examination, with amendment timing selected in consultation with Japanese counsel. That approach preserves the opportunity to choose which paths to retain instead of responding under avoidable procedural pressure.

Entry-stage amendment planning

 

A Japanese entry amendment should do more than delete the offending reference. Counsel should map the commercial and patentability value of each affected path, preserve the paths worth pursuing, and confirm that the revised wording has support in the international application. That approach avoids an overcorrection in which formal compliance is achieved by surrendering useful fallback positions. The JPO guidance includes examples suitable for a pre-entry screening checklist.

Fees

 

Japanese examination and post-grant fee schedules use the number of claims, without the U.S. system's separate multiple-dependent surcharge and dependency multiplier. JPO fee schedule. Ordinary multiple dependency can therefore reduce the numbered claim count even though nested multi-multi structures are barred.

9. Synthesis and Cross-Border Drafting Protocol

 

Multiple dependency trades printed-claim compression against visibility, local fee savings against later administrative cost, global portability against local optimization, and coverage density against amendment resilience. No office-neutral form maximizes all four. For a portfolio expected to enter all five jurisdictions, PCT Rule 6.4 supplies a sound portability baseline: state multiple references in the alternative and do not use a multiple dependent claim as the basis for another. Local counsel can then retain ordinary multiple dependency where national fee rules and examination practice justify it.

Compression should be used only when its administrative savings exceed the costs of local review, translation, fee modeling, later flattening, and claim-status tracking. Important combinations and intermediate generalizations should remain supported in the application as filed so that a prohibited or unclear branch can be rewritten without added matter.

Build a dependency matrix

 

Before international filing, create a matrix with one row for each numbered claim and fields for claim category, added limitation, direct parents, expanded dependency paths, commercial or patentability purpose, and planned national-phase treatment.

The matrix distinguishes printed claims from substantive combinations and shows which paths survive allowance, rejection, cancellation, or amendment of a parent. Treat it as a living prosecution record and recompute the paths after any renumbering or change of parent.

A national-phase workflow

 

1. Inventory and trace. Identify every ordinary multiple dependent claim. For each multiple dependent claim, trace every direct and indirect parent path and flag any path containing another multiple dependent claim. Record category changes or incompatible limitations.

2. Classify. Rank each path by commercial relevance and patentability value, preserving important combinations before eliminating remote permutations.

3. Localize. Apply destination-office form rules, correct structures that conflict with PCT Rule 6.4 before international filing when possible, and address remaining national defects before they impair search or examination.

4. Model costs. Compare claim-count fees, special multiple-dependent-claim fees, translation and review costs, and prosecution-tracking burden.

5. Verify and re-run. Confirm support in the application as filed, then recompute the dependency graph after every amendment or renumbering.

10. Conclusion

 

Multiple dependent claims expose a broader truth about global patent drafting: the same words can carry different procedural and economic consequences across offices. The United States permits ordinary multiple dependency but charges for its alternatives. The EPO offers the broadest structural flexibility among the offices examined, subject to clarity and other EPC requirements. China and Korea permit alternative multiple dependency while prohibiting nested forms, with per-claim fee components based on numbered claims. Japan preserves ordinary multiple dependency but bars multi-multi structures for applications governed by filing dates on or after April 1, 2022.

The USPTO projections are consistent with, but do not independently establish, the conclusion that fee-triggering proper multiple dependent claims are uncommon in current U.S. practice. They are projected administrative fee events, not observed incidence rates or matched application cohorts, and they do not support comparisons of usage across offices.

The practical response is controlled localization. Use PCT Rule 6.4 as a portability baseline, preserve support and a dependency map for important combinations, and adapt the claim tree only when national form, fee, and examination rules justify the change.