Consistent terminology doesn’t always mean accurate translation. See what EPO decision G 1/25 reveals about context in patent translation.
A patent claim can seem clear at first glance. The terms look familiar. The technical features appear well defined. But a closer look at the description or drawings may change how we understand them.
For patent translators, this raises a familiar question: Does the usual translation of a term really fit this invention?
On September 3, 2026, the Enlarged Board of Appeal of the European Patent Office issued decision G 1/25 (Hydroponics). It builds on G1/24 and addresses the relationship between patent claims and descriptions.
The decision deals with patent-law interpretation, not translation. Still, it touches on something we know well at Montero: a word’s meaning depends on the technology behind it.
What G 1/25 Says About Claims and Descriptions
The Enlarged Board had to answer a specific question: When amended claims no longer match the description, does the description need to change?
Not in every case.
Under G 1/25, the description must be adapted when an inconsistency leads to non-compliance with the European Patent Convention (EPC). A difference between the claims and description is not, by itself, enough to require an amendment.
The decision also builds on G 1/24. That ruling established that the description and drawings must always be consulted when interpreting patent claims, even when the wording seems clear. This also applies when assessing clarity under Article 84 EPC.
There are limits, though. The claim wording still sets the boundaries. The description cannot add limitations or extend the claimed subject matter without support in that wording.
A patent may also give a technical term its own specific meaning. Such definitions can guide interpretation if they are technically reasonable and fit the patent’s overall teaching.
For translators, that last point has a practical consequence. A familiar term may need a closer look before we choose its equivalent.
How Technical Context Shapes Patent Translation
Patent claims pack a lot of technical information into very few words. The description fills in much of the detail.
This matters when translating. A term may have several accepted equivalents, and a dictionary may offer little help in choosing between them. The answer often lies in how the invention works.
The binder in G 1/25
The case behind G 1/25 offers an example. An amended claim 1 defined a binder in a way that no longer matched paragraphs [0013] and [0016] of the description.
The Enlarged Board did not determine what binder means. It ruled on when such a mismatch requires the description to be adapted.
In a translation project, the description may explain what a component does or what makes it different from similar components. Drawings can also help a translator see how the parts fit together.
That context can change a terminology decision. A standard industry equivalent may look right at first, then prove too broad or too specific once the technical details are clear.
First understand the concept. Then choose the term.
Consistent Is Not the Same as Correct
Consistent terminology helps readers navigate a multilingual patent portfolio. If the same concept appears in several parts of a patent, using the same equivalent makes those connections easier to follow.
But an incorrect term does not become accurate just because it is used consistently.
Think about what happens when a translation team starts a new patent project. The translation memory suggests a term used in an earlier application. It looks familiar, and it has already been approved. So, should the translator use it again?
That depends on the invention.
The earlier equivalent may be perfectly suitable. Or the new patent may use the same source term for a different technical concept.
A translation memory can retrieve a previous choice. It cannot tell us whether that choice still fits. This is why glossaries and translation memories need to be used with technical judgment. They help teams work consistently, but the terminology they contain still needs to match the current document.
Three questions can guide that review:
- What does the term mean here? Look at its technical role and how the patent describes it.
- Does the equivalent fit? Check whether the target-language term conveys the same concept.
- Is it used consistently? Once the choice is sound, apply it wherever the same concept appears.
These are translation quality checks, separate from the legal test for inconsistency in G 1/25.
When Claims Change, Terminology Deserves Another Look
Patent claims often change during prosecution. An amendment may alter how a feature is defined or how it relates to the rest of the invention.
For translators, this creates a problem that is easy to overlook: confirming which version of the patent they are working from.
Imagine receiving a set of amended claims, an older description, and translations from previous filing stages. Some terms may have been right when first chosen and need a second look now.
That doesn’t mean starting from scratch. Earlier translations remain valuable. The task is to check that their terms still match the current text.
For international patent portfolio managers, three practices help:
- Version control: Confirm which claims and supporting documents apply before translation begins.
- Terminology management: Review existing equivalents when amendments affect technical meaning.
- Specialized review: Check terminology choices against the latest documentation.
Sometimes an amendment leaves the terminology untouched. Sometimes it changes what a term needs to convey.
The translation team needs enough context to tell the difference.
Good Patent Translation Starts with Technical Expertise
Understanding the invention takes more than linguistic skill. It calls for subject-matter expertise and the ability to recognize how technical concepts are used in context.
At Montero, our specialized patent translators bring that technical knowledge to their work, helping them make informed terminology choices that preserve the intended meaning throughout the patent.
Need a translation team that understands your technology? Get in touch with Montero to discuss your patent translation needs.
