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Guide · Glossary

Patent glossary: the terms you meet from brief to filing

Plain-English definitions of the patent-law terms that appear in landscapes, FTO reports and filing packages — from added matter to written description.

Updated: 28 August 2026 · 7 min read

1. A – C

  • Abstract — A short summary of the disclosure, used for search purposes only; it does not define the scope of protection.
  • Added matter — Subject-matter that extends beyond the application as filed. Prohibited by Article 123(2) EPC and Article L612-6 CPI; the most common ground on which amendments fail.
  • All-elements rule — A claim is literally infringed only if every one of its features is present in the accused product or process.
  • Bolar exemption — The statutory exemption for studies and trials required to obtain a marketing authorisation for a medicinal product (Article L613-5(d) CPI; Article 10(6) Directive 2001/83/EC; 35 U.S.C. § 271(e)(1)).
  • Claim — A single sentence defining the matter for which protection is sought. Independent claims stand alone; dependent claims refer back to and narrow another claim.
  • Claim construction — The process by which a court or office decides what the words of a claim mean, before comparing them with the prior art or with an accused product.
  • Clearance — Another name for a freedom-to-operate analysis.
  • Continuation / divisional — A later application that carries the parent's filing date for the subject-matter it shares with the parent. 'Divisional' is the European and French term; 'continuation' and 'continuation-in-part' are US concepts.
  • CPI (Code de la propriété intellectuelle) — The French intellectual-property code. 'CPI' also designates a conseil en propriété industrielle, the French patent-attorney qualification.

2. D – F

  • Design-around — A modification of a product so that it no longer reproduces at least one element of a blocking claim.
  • Doctrine of equivalents — The principle under which a product that does not literally reproduce a claim feature may still infringe if it uses an equivalent means. Tests differ by jurisdiction (function-way-result in the US; Actavis v Eli Lilly in the UK; same-function-same-result in France).
  • Double patenting — Two patents of the same owner claiming the same or an obvious variant of the same invention. In the US, obviousness-type double patenting is overcome with a terminal disclaimer.
  • Enablement — The requirement that the specification teach the skilled person how to make and use the invention across the full scope claimed without undue experimentation (35 U.S.C. § 112(a)). The European counterpart is sufficiency.
  • EPC — The European Patent Convention, the treaty under which the European Patent Office grants European patents.
  • Examination — The office procedure in which an examiner assesses novelty, inventive step, sufficiency and clarity, and in which the claims are usually amended.
  • Exhaustion — Once a patented product has been put on the market in the EEA by or with the patentee's consent, the patent cannot be used to control its resale.
  • Family — All applications and patents that share a priority claim; INPADOC and DOCDB families are the two common definitions.
  • Filing date — The date on which an application meeting the minimum requirements is received by the office. The starting point of the twenty-year term.
  • Foreign filing licence — The authorisation some countries require before an invention made on their territory is filed abroad (Article L612-9 CPI in France; 35 U.S.C. § 184 in the US).
  • Freedom to operate (FTO) — The analysis of whether a product or process can be commercialised in a territory without infringing patents in force there.

3. G – M

  • G 2/98 — Enlarged Board of Appeal decision holding that priority is only available for the 'same invention', i.e. subject-matter directly and unambiguously derivable from the earlier application.
  • G 1/15 — Enlarged Board decision establishing partial priority: a generic claim may enjoy the earlier date for the part of its scope disclosed in the priority application.
  • G 2/21 — Enlarged Board decision on post-published evidence: a technical effect may be relied on for inventive step if the skilled person would derive it as encompassed by the technical teaching and embodied by the application as filed.
  • Grace period — A period before filing during which the inventor's own disclosure does not count as prior art. One year in the US; none in Europe except in narrow cases of abuse or official exhibitions.
  • Independent claim — A claim that does not refer to another claim. The broadest statement of the invention in a claim set.
  • INPI — Institut National de la Propriété Industrielle, the French patent and trademark office.
  • Inventive step / non-obviousness — The requirement that the invention not be obvious to the skilled person in view of the prior art. The EPO applies the problem-solution approach; US law applies Graham v. John Deere and KSR.
  • Inventor — The natural person who conceived the invention. A machine cannot be an inventor (J 8/20; Thaler v. Vidal; Thaler v Comptroller-General).
  • ISR — International search report, established under the PCT by an International Searching Authority, usually around month sixteen from priority.
  • Markush claim — A claim defining a genus by listing alternative members ('selected from the group consisting of A, B and C'). Standard in chemistry.
  • MPEP — Manual of Patent Examining Procedure, the USPTO examiner's handbook.

4. N – P

  • National phase — The stage at which a PCT application is converted into national or regional applications, thirty or thirty-one months from priority.
  • Novelty — The requirement that the claimed invention not be disclosed, in a single reference, before the effective filing date.
  • Opposition — A post-grant procedure (nine months from grant at the EPO) in which a third party asks for the patent to be revoked or limited.
  • Paris Convention — The 1883 treaty establishing, among other things, the twelve-month priority period for patents.
  • PCT — The Patent Cooperation Treaty, providing a single international application and search before national phases.
  • Person skilled in the art (PHOSITA) — The hypothetical practitioner of ordinary skill and common general knowledge against whom novelty, inventive step and sufficiency are assessed.
  • Plausibility — The requirement, developed by EPO case law and framed by G 2/21, that a claimed technical effect be credibly disclosed in the application as filed.
  • Prior art — Everything made available to the public anywhere in the world before the effective filing date, in any form.
  • Priority — The right, for twelve months, to file later applications that are treated as filed on the date of the first application for the same invention.
  • Prosecution history — The written record of exchanges between applicant and office during examination; used to construe claims and, in the US, to limit equivalents (estoppel).
  • Provisional application — In France, a demande provisoire (Articles R612-3-1 ff. CPI): a filing on the basis of a description, to be regularised within twelve months. In the US, a provisional application under 35 U.S.C. § 111(b) serves a similar purpose.

5. R – W

  • Regularisation — The step by which a French provisional becomes a standard application: claims and abstract filed, search fee paid, within twelve months.
  • Restoration of priority — The exceptional procedure for a priority period missed by a short time (Rule 26bis.3 PCT; Article 122 EPC), on an 'unintentional' or 'due care' standard depending on the office.
  • Search report — The office's list of prior-art documents considered relevant to the claims, with category codes (X, Y, A) indicating their relevance.
  • Sequence listing — The standardised presentation of nucleotide and amino-acid sequences in an application, in WIPO Standard ST.26 XML since July 2022.
  • SPC — Supplementary protection certificate, extending protection for a medicinal or plant-protection product by up to five years to compensate for regulatory delay (Regulation (EC) No 469/2009).
  • Sufficiency of disclosure — The requirement that the application disclose the invention clearly and completely enough for the skilled person to carry it out (Article 83 EPC; Article L612-5 CPI).
  • Swiss-type / purpose-limited product claim — The European formats for claiming a known substance for a new medical use, since methods of treatment are not patentable in Europe.
  • Term — Twenty years from the filing date, subject to renewal fees, plus any SPC or patent term extension.
  • Unitary Patent / UPC — A European patent with unitary effect in participating EU states, litigated before the Unified Patent Court, available since June 2023.
  • Written description — The US requirement (35 U.S.C. § 112(a)) that the specification show the inventor possessed the claimed invention at filing; the closest European relative is the added-matter test.
  • White space — The region of a technology landscape not covered by any live claim: both the safest place to operate and the most promising place to file.