G 1/16 – Disclaimers – History, Decision and Practice

C. Mercer (UK)

This article was written with valuable input form D. Goodmann (GB)

There has been a great deal of interest in G 1/16, the most recent decision of the Enlarged Board of Appeal (EB). epi’s European Patent Practice Committee (EPPC) formed a Working Group to contribute to the Enlarged Board’s deliberations. The Working Group provided a first set of comments after the EB had indicated that it was seeking views from interested parties. During the EB proceedings, the EB issued a preliminary view of the points which still needed discussion and the Working Group provided a second set of comments addressing the points made by the EB. These can both be found on the epi website[1]. A member of the Working Group attended the oral proceedings.

So what is all the fuss about?


Going back to basics, the case was all about disclaimers. As we all know, a disclaimer is a negative claim limitation, typically excluding specific embodiments or areas. A simple example of a claim with a disclaimer in it is “A metal, wherein the metal is not steel”.

Disclaimers are then divided into undisclosed disclaimers and disclosed disclaimers. The example above would be an undisclosed disclaimer if there was no mention of steel in the application. However, if the application did mention steel, for instance by stating that: “In some embodiments, the metal is not steel” or, sometimes, “In some embodiments, the metal is steel”, then the disclaimer is a disclosed disclaimer. Disclaimers have been dealt with by the EB before. I will refer to the two main cases here.

Undisclosed Disclaimers

The first case is G1/03 which deals with undisclosed disclaimers. G1/03 held that undisclosed disclaimers are allowable provided that they meet a four step test. Step 1: Is there a suitable reason for a disclaimer? Step 2: Does the disclaimer remove no more than is necessary? Step 3: Is the disclaimer unrelated to inventive step and sufficiency? Step 4: Is the disclaimer clear and concise? The answer must be “yes” to each question, otherwise the disclaimer adds matter.

Step 1 can be answered with “yes” if the disclaimer restores novelty over Article 54(3) prior art or over an “accidental” anticipation in Article 54(2) prior art or removes subject-matter excluded from patentability. As to what an accidental anticipation is, in G1/03, the EB said that “… from a technical point of view, the disclosure […] must be so unrelated and remote that the person skilled in the art would never have taken it into consideration when working on the invention”. Excluded subject-matter includes such things as methods of treatment of the human body, uses of human embryos for industrial or commercial purposes etc.

Step 2 can be answered with “yes” if the disclaimer is carefully drafted so that only that which is disclosed in the prior art or that which is excluded subject-matter is covered by the disclaimer. If you disclaim too little, the claim is not allowable because it still lacks novelty or still encompasses excluded subjectmatter. If you disclaim too much, it may not be allowable under Article 123(2) EPC.

Step 3 can be answered with “yes” only if the disclaiming of the subject-matter does not have any effect on inventive step or sufficiency. As was said in G1/03: “A disclaimer which is or becomes relevant for the assessment of inventive step or sufficiency of disclosure adds subject-matter contrary to Article 123(2) EPC” (reason 2.3).

Step 4 can be answered with “yes” only if it is possible to make a precise description of the subject-matter to be disclaimed. This can be difficult if the prior art containing the subject-matter is itself unclear. However, the EPO may, in such circumstances, allow an applicant to remove more than necessary for the sake of clarity or conciseness (T 2130/11; Guidelines H-V, 4.5).

Disclosed Disclaimers

The second case is G2/10, which dealt with the question of disclosed disclaimers. The question in that case was: “Does a disclaimer infringe Article 123(2) EPC if its subject-matter was disclosed as an embodiment of the invention in the application as filed?”. If, in the case of the claim set out above, the application stated that: “In some embodiments, the metal is not steel”, then it is usually the case that the disclaimer is allowed. More interesting is the situation where the application states that: “In some embodiments, the metal is steel”. In G 2/10, the EB decided that a disclosed disclaimer is allowable if the subject-matter remaining in the claim after the introduction of the disclaimer is explicitly or implicitly, directly and unambiguously disclosed to the skilled person using common general knowledge, in the application as filed. Determining whether or not that is the case requires a technical assessment of the overall technical circumstances of the individual case under consideration, taking into account the nature and extent of the disclosure in the application, the nature and extent of the disclaimed subject-matter and its relationship with the subject-matter remaining in the claim after the amendment.

Which Case Applies?

It can be seen that the rules governing the allowability of disclosed disclaimers seem to be more strict than those applying to undisclosed disclaimers. Therefore, the question arose as to whether the rules of G 2/10 should also apply to undisclosed disclaimers as well?

Case Law of the Boards of Appeal before the Reference (July 2016)

There were two lines of cases in relation to whether G 2/10 applied to undisclosed disclaimers as well as disclosed disclaimers.

T 1870/08 held that G 2/10 applies to an undisclosed disclaimer that seeks to establish novelty over novelty-only prior art. T 2464/10 said that G 2/10 did not consider G 1/03 to be exhaustive as to the conditions that needed to be fulfilled for an undisclosed disclaimer to be regarded as allowable under Article 123(2) EPC. This means that the Gold Standard test (the test of G 2/10) should be performed in addition to the tests in G 1/03. T 1441/13 said that the G 2/10 test is the overriding principle for any amendment to be allowable under Article 123(2) EPC. This applies equally to undisclosed and disclosed disclaimers.

However, T 74/11 said that G 1/03 was the correct test for assessing the possible introduction of an undisclosed disclaimer, not G 2/10.

EPO’s Guidelines for Examination (November 2017)

The EPO’s Guidelines for Examination (H-V, 4.1; November 2017) suggest that G 2/10 applies to undisclosed disclaimers. In addition to applying the four-step test of G 1/03, the Guidelines point out that: “However, the introduction of the undisclosed disclaimer should not lead, for example, to the singling out of compounds or sub-classes of compounds or other so-called intermediate generalisations not specifically mentioned or implicitly disclosed in the application as filed (see G 2/10). More generally, the test applicable under Art. 123(2), as defined by G 2/10 (see HV, 4.2), also applies to so-called undisclosed disclaimers (see T 1176/09)”.

The G 1/16 Referral

The case from which the reference originated is T 437/14. The claim at issue contained two undisclosed disclaimers in view of accidental anticipations. The Appeal Board (AB) hearing that case felt that it should apply G 1/03 and G 2/10, but was not sure how it could do that. The AB accepted that the disclosures were indeed accidental and justified according to G 1/03. However, the AB also thought that G 2/10 was universal and, if applied, would mean that the disclaimers would contravene Article 123(2) EPC. The AB was therefore unable to decide whether the claim complied with Art 123(2) EPC.

The AB therefore referred the following questions to the EB: 1. Is the Gold Standard referred to in G 2/10 applicable to undisclosed disclaimers? 2. If the answer to 1 is yes, is G 1/03 set aside? 3. If the answer to 2 is no, may the G 2/10 standard be modified in view of G 1/03?

There were a large number of submissions made to the EB. In favour of applying the Gold Standard of G 2/10 to all disclaimers were arguments to the effect that: this would lead to a uniform concept of disclosure; G 1/03 did not define exceptions to the Gold Standard, but instead further limited the circumstances in which an undisclosed disclaimer could be used; G 2/10 did not provide any justification for not applying the Gold Standard to undisclosed disclaimers; and the Gold Standard should be applied for disclaiming excluded subject-matter only.

Against applying the Gold Standard to undisclosed disclaimers were arguments to the effect that: G 1/03 allowed a specific narrow exception to requirements of Article 123(2) EPC for legal, non-technical reasons; and by definition an undisclosed disclaimer does not have basis in the application as filed. The majority of submissions presented such arguments.

The G 1/16 Decision

The EB decided that undisclosed disclaimers need to satisfy only the G 1/03 test but that disclosed disclaimers need to satisfy the G 2/10 Gold Standard test. The main reason for this decision was that applying G 2/10 to undisclosed disclaimers “… leaves virtually no chance of an undisclosed disclaimer being allowable … where an undisclosed disclaimer is introduced into the claim it (almost) automatically follows that the subject-matter remaining in the claim after the introduction … can hardly be considered to have been explicitly or implicitly, and directly and unambiguously, disclosed in the application as filed”.

Practice Points

It is worth noting that disclaimers are still dangerous, especially because of the Article 123(2) / Article 123(3) trap. Article 123(3) EPC states that: “The European patent may not be amended in such a way as to extend the protection it confers”. If a disclaimer is judged to add matter post-grant, it will often be impossible to remove the disclaimer without impermissibly broadening the scope of the granted claim.

This should have an influence on your drafting practice. It may be better to use positive limitations instead of a disclaimer, but these can only be used if they have been included in the application. You may even want to consider including disclaimers in your drafts if it is clear that they may be needed (e.g. to disclaim subject matter that is typically excluded from patentability in Europe). In making amendments, if you are going to try using a disclaimer, then it might be advisable to provide an additional independent claim that is narrower than the claim containing the disclaimer, but which recites positive limitations only. Another option is to file a divisional with an alternative limitation that addresses the novelty or excluded subjectmatter issue in a different way. Certainly, if you have to use an undisclosed disclaimer, it should be as narrow as possible to exclude only the subject-matter which needs to be disclaimed. Finally, you should ensure that all of the claims that are dependent on a claim containing an undisclosed disclaimer also require that disclaimer. If a dependent claim recites a limitation that already addresses the prior art or excluded subject-matter issue, then the incorporation of an undisclosed disclaimer through a claim dependency may add matter.


It almost seems that there was a fuss over nothing as the EB basically left a clear distinction between disclosed and undisclosed disclaimers. However, the EB decision does make it plain that the provisions in G 2/10 are not to be applied in the case of undisclosed disclaimers. Moreover, the fact that the EB keeps considering disclaimers means that they are trouble and should be avoided.

  1. http://patentepi.org/en/epi-papers/g1-16-oral-proceedings.html