Treat every patentability question as a two-step routing problem: chart the claim elements against the cited art, determine whether a single reference discloses everything (novelty) or whether a combination is needed (inventive step), and write the argument that matches the routing. The same charting habit then supports claim amendments and infringement analysis, which is why it is the first skill to drill and the last to skip.
One claim, two tests: separating novelty from inventive step
Novelty asks whether one single prior-art reference discloses every claim element. Inventive step asks whether a person skilled in the art could readily arrive at the invention from the art as a whole. Blend them and your answer answers neither.
A novelty analysis is strictly element-by-element against one reference, including matter that would be directly and unambiguously understood from that reference. If any claimed element, range, or structural relationship is absent, novelty stands, and that is the end of the novelty discussion. Common failure mode in study answers: describing why the invention is 'better' than the reference. Better results are irrelevant to novelty; the only question is disclosure.
An inventive step analysis compares the claimed invention with the closest prior art and asks whether a skilled person would have found the difference obvious, typically by combining another reference or common general knowledge. Here, motivation matters: the secondary reference must plausibly be consulted to solve the same problem or fit the same use context. An amendment that adds a distinguishing element usually rescues novelty but can simultaneously weaken inventive step by making the change look like a routine design choice.
- Novelty rebuttal: point to the specific missing element in the single reference.
- Inventive step rebuttal: attack the motivation to combine, or the teaching-away in the art.
- Amendment risk: a new distinguishing feature can be recast as an obvious selection.
| Question asked | Novelty | Inventive step |
|---|---|---|
| Body of art compared | One reference, read as a whole | Closest art plus combinations and general knowledge |
| Standard of disclosure | Every claim element must be found expressly or inherently | Difference must be obvious to a skilled person |
| Typical rebuttal | Identify the absent element or feature | Show no motivation, synergy, or teaching toward the difference |
| Amendment trade-off | Adding a missing element restores novelty | The same addition may be argued to be an obvious choice |
Worked scenario: answering a two-reference rejection the wrong way
An examiner cites reference A (a bottle with a filter) and reference B (a bypass valve in a coffee machine) against your claim. Arguing only that the combination 'would not be obvious' skips the step that protects you.
The plausible mistake: the candidate writes three paragraphs on why a skilled person would not combine a bottle filter with a coffee-machine valve, and never checks whether reference A actually discloses the valve at all. If A lacks the valve, the claim is novel over A alone regardless of B, and that element-by-element finding is the strongest sentence in the answer. By jumping to inventive step, the candidate implicitly treats novelty as lost and fights on the examiner's chosen ground.
The better decision: open with a two-column chart listing each claim element against reference A. Mark 'disclosed' or 'not disclosed' per element. The valve row reads 'not disclosed,' so the novelty argument writes itself and consumes one sentence. Only then argue, conditionally, that even if B were considered, it teaches a hot-liquid machine for a different purpose, so combining it is not straightforward. Why it matters: the chart forces the examiner's rebuttal to engage with a specific element rather than a general impression, and it keeps your inventive-step fallback from conceding anything.
From validity to infringement: literal scope first, equivalents second
Infringement analysis runs in the opposite direction from prosecution: map the accused product against the claim literally first. The doctrine of equivalents is a fallback for elements the accused product does not literally meet, and it carries its own limits.
Start with claim construction, then compare the accused product element by element against the construed claim. If every element is present, infringement is literal and the equivalents question never arises. Under Korean practice, the all-elements principle generally means a product missing even one claimed element falls outside literal scope. The plausible mistake in an exam answer: declaring 'no infringement' the moment one element is missing, without mentioning equivalents at all.
The disciplined answer continues: whether the missing or substituted element can be captured under the doctrine of equivalents, weighed against recognized constraints such as limitations that arose during prosecution, matter already in the public domain, and whether the substitution was foreseeable or changes an element essential to the invention. Practice stating these limits as a checklist rather than a vague appeal to fairness. Why it matters: the two-stage structure — literal, then equivalents with limits — is the same scaffold whether the question is a hypothetical infringement dispute or a discussion of how amendment wording narrowed a claim.
- Step 1: construe each claim term before comparing anything.
- Step 2: literal map — every element present or not.
- Step 3: equivalents only for the missing or substituted element.
- Step 4: test equivalents against prosecution history, prior art, foreseeability, and essentiality limits.
Worked scenario: choosing between the Paris route and the PCT route
A Korean applicant with a first filing at home must later decide how to seek protection in other countries. The common confusion: treating a PCT application as if it were a patent, or assuming one filing protects every country.
Scenario: a Korean applicant files a first application at home, then develops the invention further and wonders how to preserve rights overseas. The plausible mistake is to believe the PCT 'grants international protection' or that a first filing automatically extends abroad. Patent rights are territorial, so protection in each jurisdiction requires an application reaching that jurisdiction's office, within the priority period preserved by the first filing.
The better decision: lay out the two routes side by side. Under the Paris Convention route, the applicant files directly in each chosen country within the priority year following the first filing. Under the PCT route, a single international application preserves the priority and defers the national-phase decisions in the designated states until later, buying time to assess markets and results from the international search. Why it matters: exam questions on treaties turn on knowing which step happens when, and what the international application does and does not deliver. Confirm current timing rules for each office from the office itself rather than from memory of a textbook figure.
Post-grant pressure: opposition, invalidation, and what prosecution history costs you
After grant, an invention can be attacked through opposition procedures, through invalidation proceedings, and indirectly by narrowing claim interpretations based on the prosecution record. Each channel has different timing and grounds, and conflating them loses marks.
Keep three distinctions sharp. Opposition systems generally allow third parties to challenge a newly granted patent within a short statutory window, on specific grounds. Invalidation proceedings, such as Korea's trial system, typically remain available over the life of the patent and can rest on grounds like lack of novelty or inventive step. Separately, a defendant in an infringement action can raise invalidity as a defense within the litigation and may also pursue a separate invalidation trial before the patent tribunal. Matching the right channel to the facts is the analytical core of these questions.
Prosecution history feeds all three channels. Every statement an applicant makes to distinguish prior art — 'the valve is essential,' 'reference B teaches away' — can later narrow how the claim is construed or bar an equivalents argument that contradicts it. When you draft amendments in practice questions, annotate each one with what it would concede later. Why it matters: this connects drafting decisions made in the first hour of a case to enforcement outcomes years later, which is exactly the integrated reasoning the exam can test.
- Opposition: short window, limited grounds, third-party initiated.
- Invalidation trial: longer availability, broader grounds, affects the whole claim if successful.
- Maintenance: periodic fee lapses can end a patent without any challenger.
- Prosecution history: an interpretive weapon against the patentee, not the challenger.
Scored exercise: chart, argue, and audit one real patent
Pick one granted patent in a technology you know. In under an hour, produce an element chart against two references you find yourself, one novelty sentence, one inventive-step sentence, and one infringement map against a hypothetical device — then score it.
Exercise instructions: (1) List every element of independent claim 1 down the left column. (2) Fill in rows for reference A and reference B with 'disclosed / not disclosed / unclear.' (3) Write one sentence of novelty argument citing the absent element by name. (4) Write one sentence of inventive-step argument addressing motivation to combine. (5) Invent an accused product omitting one element and write a two-step infringement conclusion (literal, then equivalents with at least two limits named). Expected observations: your chart should contain at least one 'unclear' cell; resolving it — express disclosure, inherent disclosure, or absent — is where the analytical work lives.
Self-check rubric, scored 0–2 per item, total out of 12 (learning milestones only, not a prediction of any exam result): chart completeness (every element listed); disclosure accuracy (cells justified, not guessed); novelty sentence (names the element); inventive-step sentence (addresses motivation, not quality); infringement map (element-by-element, not impressionistic); equivalents limits (at least two named correctly). A score of 9 or above means the routing habit is forming; below that, repeat the exercise with a mechanical rather than a chemical invention.
An adaptable preparation sequence with concrete readiness checks
Sequence the syllabus so doctrine precedes drafting and drafting precedes enforcement: patentability first, claim language second, infringement and treaties third, post-grant last, then mixed timed sets.
A ten-week adaptable plan: weeks 1–2, novelty and inventive step with the chart drill from the exercise above on three different claims; weeks 3–4, claim drafting — rewrite the abstracts of granted patents into claims, then chart your own claims against the original; weeks 5–6, infringement and equivalents, including writing answers that deliberately stop after the literal step and then extend; week 7, priority and PCT mechanics with a dated timeline sketch per route; week 8, prosecution procedure, opposition, invalidation, and maintenance; weeks 9–10, mixed timed sets alternating one patentability answer with one infringement answer. Adjust the weighting toward your weakest rubric score, not equally.
Readiness checks before the exam: (1) you can produce a full element chart from an unseen claim and reference within a self-imposed time limit; (2) every argument you write names a specific element or a specific motivation rather than a conclusion; (3) you can state the equivalents limits from memory and attach each to a one-line example; (4) you can draw the Paris-versus-PCT timeline without consulting notes; (5) your amendment drafts include a note on what each change concedes. Note that exam schedules, eligibility, and administrative details are set by the exam administrator's official announcements — verify those there, and use this guide for doctrine and method.
- Weeks 1–2: charting drill on novelty and inventive step.
- Weeks 3–4: claim drafting and self-charting.
- Weeks 5–6: literal and equivalents infringement answers.
- Week 7: priority and PCT timelines.
- Week 8: opposition, invalidation, maintenance.
- Weeks 9–10: mixed timed practice sets.
References and further reading
Use these references to explore the concepts and check the latest information from the relevant organizations.