Principle

Once the application is filed, the framework of the invention is set.

If subsequently the proprietor seeks to modify their claims to cover a « new invention » that they had not thought of at the time of filing (e.g., a competitor’s product close to their invention), it is normal to refuse this modification (Guidelines H-IV 2.1).

This is the principle of A123(2) EPC:

The European patent application or the European patent may not be amended in such a way that it contains subject-matter which extends beyond the content of the application as filed.

Subject-matter of the application

The « subject-matter » of the application within the meaning of A123(2) EPC includes:

  • the elements describing the invention (A83 EPC);
  • the presentation of the problem posed;
  • the solution;
  • the advantages it brings (R42(1) c) EPC).

Thus, there may be an extension problem for all these points, and not only for the claims, as is generally accepted.

Content of the application as filed

Included

Explicit disclosures

From the description

Of course, explicit disclosures in the description are part of the content of the application (G11/91).

From the claims

For the claims, they are part of the application if they were filed on the filing date (G11/91).

Disclosures from the drawings (under conditions)

The drawings are also part of the disclosure of the application (G11/91).

The drawings can also serve as a basis for a modification if, in the light of the rest of the document (T676/90):

  • the disclosure is clear and unambiguous (Guidelines H-V 6);
  • the disclosure is not a « negative » feature (absence of… T170/87);
  • the disclosure is not a measurement of the drawings (T523/88, unless a scale is indicated, T398/92);
  • The support for such a modification must clearly be perceived by the person skilled in the art as intentional (and not accidental) and deliberate on the part of the inventor in order to solve the technical problem (T398/00).

It should be noted that if the drawings are filed in color, the color can be used to understand the meaning of them and their scope (even if the color is a formal irregularity, T1544/08).

Implicit disclosures

Implicit contents are also part of the content of the application (T1599/18).

A disclosure is implicit if the characteristic object of the disclosure is imposed on the person skilled in the art as being the only and unique possibility given the explicit disclosures (i.e., a clear and unequivocal consequence of what is explicitly mentioned, Guidelines G-VI 6).

It is also said that the disclosure follows directly and unambiguously from the application (T514/88).

By way of illustration, the disclosure of a pair of shoes does not necessarily imply the presence of laces (scratches or other fastening systems may exist): laces are therefore not an implicit disclosure.

However, the disclosure of an airplane necessarily implies the existence of wings: wings are then implicit disclosures.

The decision T1599/18 even indicates that several alternatives can be implicitly disclosed: Thus, this decision does not consider that the notion « unequivocal » means that there are no multiple choices/alternatives/solutions.

Documents cited in the application (under conditions)

The content of the documents cited in the application is part of its content only if (Guidelines H-IV 2.3.1) it clearly emerges from the description of the invention as filed (T689/90) that, cumulatively:

  • protection is or could be sought for these characteristics;
  • these characteristics contribute to solving the technical problem of the invention;
  • these characteristics are included (at least implicitly) in the description of the invention;
  • these characteristics can be identified precisely in what the reference document discloses;
  • the cited document is accessible (T737/90):
    • to the EPO: on the filing date of the application,
    • to the public: on the publication date of the application.

Are not part

Abstract

The abstract is not part of the disclosure (T246/86 and Guidelines F-II 2.2).

Priority document

Priority documents are not part of the content of the application as filed (T260/85 and Guidelines H-IV 2.2.5).

Claims produced after filing

Similarly, the claims produced after filing (and contrary to the description or figures produced after filing, Guidelines H-IV 2.3.2) are not part of the content of the application as filed (Guidelines H-IV 2.3.3).

Analysis of the extension

Principle

Directly and unambiguously

There is an extension of the application if the modification does not follow directly and unambiguously from the information contained in the application as filed, even taking into account implicit elements for the person skilled in the art (Guidelines H-IV 2.2).

Application by the Unified Patent Court (UPC)

The UPC (UPC, CD Paris, 5 Nov. 2024, NJOY v. Juul, UPC_CFI_309/2023) recalled that the criteria for assessing modifications are aligned with those of the EPO, requiring that any modification be directly and unambiguously derived from the content of the application as filed. This decision also highlights Article 65(3) of the Agreement on the Unified Patent Court (AUPC), which allows for partial revocation of a patent.

Interpretation

To identify whether the modification causes an extension of content, all reasonable interpretations of the modification should be considered (T1791/16).

If a claim is ambiguous or unclear, all technically reasonable interpretations must be taken into consideration. It is sufficient that one of them contains subject-matter which extends beyond the application as filed to deduce the presence of added matter.

For the application of A123(2) EPC, A69(1) EPC and its interpretative protocol apply. The claims must be interpreted in their context, including the description and the figures, by a person skilled in the art. Only the technically reasonable interpretation is retained (T367/20, T556/02, T1599/18).

A question of scope?

Some people have already told me that a modification of the claims should be analyzed, with regard to A123(2) EPC, in terms of the scope of the claims: is the new scope of the claims supported by the description?

Nothing could be more false: the scope of the claims is not the criterion here…

Indeed, it is quite possible to modify the claims without modifying their scope, while the modification would be contrary to the provisions of A123(2) EPC (e.g., modification of an initial claim « device made of metal… » to « device made of metal, for example aluminum, … »).

Use of A69 EPC?

When we analyze an extension, we can legitimately ask ourselves whether A69 EPC should be used: should the claims be interpreted in the light of the description?

The answer is yes (T516/18 and T1473/19, 3.15), whether it is for an extensive interpretation of the scope or a restrictive one.

Using the description and the drawings to interpret the claims is permitted (T2475/18) and even necessary if the person skilled in the art, even with the will to understand, is faced with unclear and/or inconsistent features. For the assessment of patentability, the Enlarged Board requires that they always be consulted, and not only in case of unclarity or ambiguity (G1/24).

However, the primacy of the claims limits the influence of the description: a limiting feature that appears only in the description cannot be read into the claim, and the description cannot be used as a dictionary to give a term a meaning incompatible with its ordinary meaning (T1473/19, 3.16.1 and 3.16.2).

Furthermore, there is no principle according to which a claim should be interpreted so as to make it comply with A123(2) EPC (T1473/19, 4.4): the goodwill of the reader has its limits.

For A123(2) EPC, the boards disagree on the application of G1/24, but they reach the same result: the description cannot be used to "rescue" an amendment.

  • T405/24: G1/24 only concerns A52 EPC to A57 EPC; in any event, all technically reasonable interpretations of the contested feature must be taken into account, and not only the interpretation supported by the description (T405/24, 1.2.3);
  • T2488/22: the description and drawings must be consulted for all requirements of the EPC, the claims having to be interpreted uniformly (T2488/22, 16); however, restricting the claim to an embodiment that its wording does not require would deprive A123(2) EPC and A100(c) EPC of their meaning (T2488/22, 20 and 21);
  • T156/25: the application as filed may shed light on the interpretation and resolve a genuine ambiguity, but it cannot neutralise a feature added by amendment that has a coherent technical meaning (T156/25, 9.1 to 9.3).

The question has now been put to the Enlarged Board (third question of referral G1/26, from T873/24). See the article "Decisions of the Enlarged Board of Appeal".

Modification of drawings

If the drawings are modified based on drawings filed that were not in the language of the proceedings, there is no extension beyond the content as filed (T382/94).

Addition of features

When adding a feature to the application, it should be analyzed whether this feature directly and unambiguously derives from the application as filed (Guidelines H-IV 2.2 and T201/83).

It is not necessary for this feature to have a technical contribution (G1/93).

If so, this addition should be considered as meeting the criteria of A123(2) EPC.

Disclaimer

If, for legal reasons (e.g., to avoid an exception to patentability), a disclaimer is added, it is acceptable if it does not modify the technical content of the disclosure (G1/03 and G2/03).

For an undisclosed disclaimer, it is these criteria that apply, and not the « Gold standard » of G2/10: the disclaimer must not provide any technical contribution nor remove more than necessary (G1/16).

An undisclosed disclaimer based on an earlier application of the same applicant is in principle not allowable: for the examples of that earlier application, the later application cannot validly claim priority (it is not the first application), so that the earlier application, published before the filing date, is prior art under A54(2) EPC and not under A54(3) EPC; not being accidental, it cannot form the basis of a disclaimer under G1/03. The assessment is made on the claim before the disclaimer is inserted, in the light of G1/15 (T88/21, 1.3 to 1.7, departing from T1872/14).

The reverse situation is no simpler: the deletion of a disclaimer present in the application as filed, which expressly presented the excluded subject-matter as not forming part of the invention, contravenes A123(2) EPC if it leads to claiming, even partly, that excluded subject-matter. It does not matter that the application is a divisional and that the disclaimer was introduced for patent law reasons (e.g. prior art under A54(3) EPC) (T2327/18, 6.3, 7 and 8.3, relying on G2/10, 4.5.5).

Addition of non-technical limitations

It may happen that the claims are limited, during the procedure, in a non-technical manner (e.g., restriction of the claimed method to only certain times, or to only certain parameters).

In this hypothesis, the boards of appeal seem to consider that these limitations are not prohibited by A123(2) EPC (T1779/09): the principle here seems to be to prevent the proprietor from falling into the « pincers » of A123(2) EPC and A123(3) EPC.

However, an amendment concerning an element that is non-technical in itself escapes A123(2) EPC only if, in its context, it does not provide the skilled person with any new technically relevant information (T433/22, 1.2.3, relying on G2/10, 4.5.1, contra T619/05). This was the case there: replacing a frequency band "permitted" at a higher transmission power with a band "designed for" that power removes a feature that contributed to solving the technical problem (compliance with emission standards), and teaches that the power is no longer limited (T433/22, 1.2.5).

Deletion/substitution of features

The essentiality test or triple test

The deletion/substitution of features of a claim is possible if (Guidelines H-V 3.1 and T331/87):

  • this feature is not presented as essential in the disclosure of the invention,
  • this feature is not indispensable, as such, to the realization of the invention with regard to the technical problem that it proposes to solve, and
  • its deletion/substitution does not require truly modifying other features accordingly.

This test is most often called the « essentiality test » or the « triple test ».

Towards the end of the essentiality test or triple test

Some decisions challenge this test (T1852/13 or T1462/14) or at least affirm that this test does not define sufficient conditions: other conditions may be added depending on the case.

Indeed, it is noted that the decision T331/87 establishes a test in a specific case and does not affirm that this test is absolute (« may not violate A123(2) EPC« ).

For the board of appeal (T1852/13 or T172/17), the « Gold standard » (i.e., directly and unambiguously) must always apply (and it is much more restrictive than the triple test).

Thus, replacing a functional feature presented as necessary (e.g. a free biocide content such that the glass transition temperature of the binder does not drop by more than 20 °C) with a numerical value disclosed elsewhere is not allowable if the application does not teach that the two are equivalent. And the lack of clarity of the original feature is no excuse: it is attributable to the applicant, who drafted the application (T1099/21, 4 to 8).

Selection from two lists

Non-convergent lists

Making a selection from multiple non-convergent lists is not admissible under A123(2) EPC (T727/00 or T686/99).

A non-convergent list is a list of the type: « A or B or C or D« .

Furthermore, selecting two compounds from a single list is equivalent to selecting compounds from two identical lists and is therefore not admissible (T1374/07).

A list does not need to have any particular format (table, bullet points…): as soon as the application presents several items as equally preferred, they form a list. Thus, three independent claims with the same wording, each directed to one compound, form a list, and the fact that a compound is individualised in one of them is not a pointer to that compound (T1442/19, 2.4.1). It would be different for a dependent claim that is not in competition with other dependent claims (T2635/18, 3.1.1).

These considerations remain true even if the description includes a phrase such as « any combination of …« . Indeed, the number of combinations is often too large for a particular combination to be disclosed « directly and unambiguously » (T1374/07).

Convergent lists

The situation is more flexible if we are dealing with convergent lists (T2237/10 contra T812/09).

A convergent list is a list of the type: « A or preferably B or even more preferably C« .

However, not every selection from lists of convergent alternatives is automatically compliant with A123(2) EPC. According to T1621/16, at least two conditions are necessary:

  • the combination must not be associated with an undisclosed technical contribution (T1621/16 and T1020/21);
  • the combination must be supported by a pointer (examples, specific embodiments…).

However, some decisions do not go in this direction for the first condition. Apart from the special case of G1/93 (conflict between A123(2) EPC and A123(3) EPC), the notion of "technical contribution" has no relevance for assessing an amendment: only the « Gold standard » of G2/10 counts, i.e. what is directly and unambiguously disclosed (T1937/17, 4.3 and 4.3.1, contra T1621/16).

As for the second condition, examples are not always a sufficient pointer: where the claim results from a multiple selection among numerous dependent claims and parameters with various degrees of preference, examples that all fall within the most preferred options do not point to the intermediate combination claimed (T1137/21, 1.4 to 1.8, in line with T389/13 and T2273/10).

Combination of embodiments

The content of an application must not be considered as a reservoir from which features specific to distinct embodiments of the application can be extracted and combined in order to artificially create a particular embodiment (T296/96, T1206/07 ; T1239/08 ; T1648/11, T1799/12, T1853/13).

In the absence of any indication regarding the particular combination concerned, the corresponding selection of features does not clearly and unambiguously emerge for the person skilled in the art from the content of the application as filed (T686/99).

Combination of claims

We might think that combining claims does not violate A123(2) EPC.

In reality, this is not at all obvious (T389/13).

The test to be applied is based on what would be directly and unambiguously derived by the person skilled in the art from the application as filed, which implies analyzing the different features of the dependent claims in question and their relationships, as disclosed in the application, either explicitly, for example by a direct link, such as a reference to other claims, or implicitly, by analyzing their function and interactions.

Intermediate generalization

« Intermediate generalization » refers to extracting a feature from the description and isolating it from its context (e.g., a given embodiment, Guidelines H-V 3.2.1).

Such generalization is only possible if:

  • the extracted feature is not inextricably linked to the other features of this embodiment (T714/00),
  • the non-extracted features of this embodiment satisfy the essentiality test mentioned above,
  • the general disclosure justifies the isolation of the extracted feature, leading to a generalization, and its introduction into the claim.

This can particularly occur when the omitted features have their own function, independently of the rest of the system (T461/05).

According to T1762/21, Guidelines H-V 3.2.1 are to be read in the light of the « Gold standard »: features described together with the claimed ones, even if important for the general operation of the apparatus, may be omitted if the skilled person does not regard them as necessary to obtain the effect associated with the claimed features (e.g. anti-scatter grid, filter, collimator or rotating anode of a breast tomosynthesis system whose invention concerns the optimisation of the focal spot, T1762/21, 2.4 and 2.5).

Reformulation of the technical problem

In theory, A123(2) EPC is not relevant concerning the simple reformulation of the technical problem (T654/89). It becomes relevant if the applicant wants to add this reformulated technical problem to the application (Guidelines G-VII 11).

A reformulation of the technical problem is possible if the person skilled in the art can deduce the formulated problem from the application as filed and in light of the closest prior art (T13/84 and Guidelines H-V 2.4).

Case of a disclosure of ranges

Mixing of range limits

It may happen that an application discloses:

  • the presence of a compound X in a solution (i.e., greater than 0%),
  • the fact that preferably the compound X is between 5% and 20%;
  • the fact that even more preferably the compound X is between 8% and 15%.

The question that arises is whether it is contrary to the provisions of A123(2) EPC to claim:

  • between 5% and 15%;
  • between 0% and 15%;
  • etc.

The answer is « yes« : many decisions have recognized the applicant’s right to combine ranges together (T2/81, T1170/02).

However, it is forbidden to combine the two lower limits of the disclosed ranges to create a new sub-range (e.g., here, between 5% and 8%): the new sub-range does not correspond to a combination of disclosed ranges (T1170/02).

Use of a particular value as a limit

It may happen that a range [1; 1000] is claimed and that the value of 200 is given as an example.

The question that arises is whether one can claim the range [200;1000] or [1; 200].

In this case, it will depend on what is indicated in the application, but if the application teaches that any range can be used, the person skilled in the art would understand that the value 200 can serve as a limit (T1556/16).

Exclusion of an endpoint

It may also be necessary to consider the exclusion of an endpoint.

Indeed, if the interval [0;15%] is described in the application, is it possible to claim « less than 15% » (i.e., strictly less than 15%).

There is no definitive answer in all technical fields, but this has been allowed in the field of chemistry (T83/13): indeed, in chemistry, the person skilled in the art cannot see a difference between a concentration of 15% and a concentration of 14.9999%. Therefore, the technical teaching is the same.

However, it is worth noting the decision T1990/10 which goes in the opposite direction.

Addition of a state of the art

The mention of a state of the art in the description does not pose a problem of extension beyond the content as filed (T11/82 and Guidelines F-II 4.3).