The same invention may receive very different examination results at the USPTO, the EPO and the JPO, because the three offices differ systematically in inventive step, amendment flexibility, functional limitations and specification support.
Why can one invention produce different results?
The same invention may receive very different examination results at the USPTO, the EPO and the JPO, because the three offices differ systematically in how they judge inventive step, how much amendment flexibility they allow, how they interpret functional limitations, and what support requirements they impose on the specification. Understanding these differences explains why one PCT application yields grants of very different quality across jurisdictions and is the starting point of any drafting strategy for foreign filing.
I. Six dimensions where the offices diverge
| Dimension | USPTO | EPO | JPO |
|---|---|---|---|
| Inventive step methodology | Graham v. John Deere factors and flexible obviousness analysis after KSR v. Teleflex (2007) | Problem-Solution Approach anchored on the objective technical problem | Inventive step tested by whether a chain of logical reasoning holds; conceptually close to the EPO |
| Combining prior art | Multiple references combinable; motivation requirement relaxed after KSR | Starts from a single closest prior art, then asks whether the skilled person would combine | Starts from a primary reference; secondary references require an articulated motivation |
| Amendment flexibility | High: continuation, CIP and divisional practice allow new claims on the same specification for years | Low: amendments need “direct and unambiguous” basis (Art. 123(2) EPC); after grant, Art. 123(3) closes the “inescapable trap” | Medium: prosecution amendments restricted (no shift amendments); limited post-grant changes via correction trial |
| Functional limitations | Once §112(f) applies, scope is narrowed to disclosed embodiments and equivalents | Functional features allowed, but the effect must be achievable across the full claimed range | Broadly accepted, subject to adequate support under the Examination Guidelines |
| Specification support | Written description and enablement (§112(a)); particularly strict in life sciences and materials | Art. 83 sufficiency, plus Art. 84 clarity and support | Enablement and support requirements; parameter-defined inventions examined strictly |
| Pendency (qualitative) | Moderate; paid Track One acceleration is available | Longest of the three; a nine-month opposition window adds post-grant uncertainty | Fast once examination is requested, with accelerated and super-accelerated tracks |
Of the six, the first three matter most to foreign applicants: the inventive-step method dictates how responses must be argued, the combination rules dictate how examiners reject, and amendment flexibility dictates how much room the text leaves later.
II. Why one literal translation is the most expensive option
Filing the same claim set, literally translated, into all three offices looks like a drafting saving. In practice, it loses on three fronts at once.
1. At the EPO, you run out of amendment basis. The “direct and unambiguous” standard of Art. 123(2) is the strictest of the three; generalizing amendments and feature recombinations that pass routinely in the US are refused for lack of literal basis. If the specification was not drafted with intermediate generalizations, there is simply no ammunition left when the objection arrives.
2. At the USPTO, you waste the system's biggest gift. Without a claim-tier plan built around continuation practice, you forfeit the ability to reshape claims around a competitor's product later — the “second chance at claim strategy” that exists nowhere else.
3. At the JPO, you buy avoidable office actions. Multiple-dependency style and unity-of-invention differences generate formal rejections that a localized claim set would never have triggered.
The practical answer is to invert the logic: draft the specification to the strictest of the three standards at the PCT stage. Write intermediate generalization layers level by level (for EPO amendment limits); spread embodiments across parameter gradients and variants (for US written-description scrutiny and §112(f) narrowing); state explicitly which features produce which technical effects (for JPO support requirements). Then, at national phase entry, tailor the claims per office at marginal cost. Redundancy in the specification is ammunition for portfolio strategy, not a drafting cost — every extra generalization layer and embodiment is an option that pays off precisely when one office demands it.
III. Using Japan as an early test bed
The pendency gap between the offices is itself a strategic resource. JPO examination is fast once requested and its citations are consistently relevant, so it can pay to push the Japanese family member into examination first: the prior art surfaced in a Japanese office action frequently foreshadows what the EPO and USPTO will cite later, buying months of preparation time for the European and American responses — one low-cost examination sweeping for mines ahead of the whole family. A positive Japanese result can then be leveraged through the Patent Prosecution Highway (PPH) to accelerate examination in the US and elsewhere, converting the time gap into faster grants. Two cautions: statements made to the JPO enter the global file history and must be managed for consistency across the family; and PPH requires claims to “sufficiently correspond” to the allowed set — check that this correspondence does not import an unnecessarily narrow scope into other jurisdictions.
IV. A working checklist
1. Drafting stage: write the specification to the strictest standard; prepare an aggressive and a conservative independent-claim version for offices to choose between.
2. Entry stage: select offices by market weight and competitor filing density (main sales market > competitors' home turf > manufacturing base).
3. Prosecution stage: let Japan scout first; keep a continuation plan alive in the US; self-check every EPO amendment against Art. 123(2) before filing it.
4. Family management: align argument language across all three offices, so a statement that wins in office A does not become estoppel evidence in office B — or in court.
FAQ
Q1: Why does the same patent get granted in the US but refused in Europe? Two causes dominate. First, once the EPO reformulates the objective technical problem under the Problem-Solution Approach, the inventiveness story often collapses — the American-style “the examiner showed no motivation to combine” argument has no receiving slot in the EPO framework. Second, added subject-matter: generalizing amendments accepted in US practice are routinely held to lack basis under Art. 123(2). Part 4 of this series dissects the Problem-Solution Approach in full.
Q2: With a limited budget, which office should we enter first? There is no universal answer, but there is a stable ordering: main sales market first, then competitors' registration and manufacturing bases. Refine quantitatively: dense competitor filings at an office signal a high-conflict market where defensive value rises; sparse filings may justify downgrading to watch status. Both instinctive “file everywhere” and “US only” are common forms of budget mismatch.
Q3: Why is US continuation practice called a “second chance at claim strategy”? As long as a parent application remains pending, new claims can keep being filed on the same specification — including claims drafted after seeing a competitor's product, aimed at it. No other major office offers this dynamic tool, and it is where specification redundancy pays off most directly. Part 2 of this series covers the mechanics and strategy.
Q4: What comes next in this series? Part 2: US continuation practice (Continuation / CIP / Divisional) explained. Part 3: advanced office action response strategy with outcome data. Part 4: the EPO Problem-Solution Approach, a practitioner's breakdown. Part 5: answering §103 obviousness rejections after KSR.
About this series
Part 1 of the US & European Patent Practice in Depth series by Suzhou WISPRO Intellectual Property Agency (Agency Code 32235), drawing on the firm's prosecution experience before the USPTO, EPO, JPO and other major offices. The firm focuses on high-quality drafting and international patent portfolio strategy.