- The EPO requirement to amend the description to conform with allowed claims is changing significantly. Examiners have already been given internal guidance and revisions to the EPO Guidelines for Applicants are expected in March 2021.
- Key changes include the requirement to delete embodiments not covered by the claims or prominently mark this subject-matter as not being part of the invention.
- It is doubtful that amending ‘embodiment’ to ‘instance’, or ‘invention’ to ‘disclosure’ (either on a passage by passage basis or on a ‘blanket’ basis) will be sufficient under the new Guidelines to ‘prominently mark’ subject-matter.
- The description is used to interpret the claims and so how the description is amended can have a significant impact on claim interpretation in post-grant opposition and national litigation proceedings, and so this change is important.
Based on our experience, and having also spent time speaking to EPO Examiners since issue of their internal guidance, we have assembled a ‘toolbox’ of strategies for amending a description in advance of the official release of the new Guidelines. Based on the extensive EPO Opposition and Appeal experience of CMS patent attorneys as well as important input regarding national considerations from CMS patent litigators from the UK, France and Germany, we understand that there can be high risks associated with adopting a one-size-fits-all approach to amending a description. We are able to assess the pros and cons of various approaches to ensure that the best one is adopted for each individual case.
This article discusses the expected changes and identifies the possible issues, particularly from a life sciences and chemistry perspective, that might arise and which will need careful consideration with your EP counsel.
Since the introduction of the EPC in 1973, approaches for amending the description have developed over time and the often complex considerations for a strategy for amending the description can come as a surprise to Applicants from different jurisdictions which do not have this requirement, such as the US.
Perhaps due to the variety of different approaches taken, the EPO appears to consider that harmonisation is required. Revisions to the EPO Guidelines are expected in March 2021 but, importantly, EPO Examiners have already been given internal guidance, and this now is evident in Examination Reports issued by the EPO. However, until the revision of the EPO Guidelines is published, Applicants have little guidance as to the EPO’s expectations for the many different types of scenario that might arise. Further, even when the Guidelines are published, it seems likely that there will still be uncertainty as to the best practice for meeting the EPO’s requirements whilst also minimising any risks for the Applicant.
So, what’s all the fuss about?
Where does this requirement come from?
The requirement stems from Rule 42(1)(c) EPC, which states that “the description shall disclose the invention, as claimed, …”. Current EPO Guidelines describe examples of inconsistencies that might exist between the description and the claims, as well as stating some of the more formal requirements that the description must conform to.
The current approaches for amending a description to address the EPO’s more formal requirements are, in general, fairly standardised. These include including a sentence stating that ”the invention is as defined in the claims” and removing any clause-like statements from the description. However the patent attorney profession as a whole has adopted a range of approaches for adapting the description in order to address whether subject-matter in individual passages falls within the scope of the claims, for example passages that might relate to broader subject-matter than that claimed or perhaps to a different embodiment.
One approach is to reword such passages to refer to the subject-matter of the claims, although extreme care must be taken with this approach to avoid changing the meaning of a passage and adding subject-matter. Another approach is to delete such passages, although for some specifications this could amount to deleting large portions of text. Many attorneys prefer to avoid deleting passages by amending these to instead recite e.g. “in one instance” or “the present disclosure” rather than “in one embodiment” or “the present invention” (an approach which has arisen out of the current EPO Guidelines). In some cases, rather than taking an approach that requires consideration of every sentence of the description, a more ‘blanket’ approach is adopted of amending all occurrences of “invention” or “embodiment” throughout a description. These different approaches each have associated risks and benefits, and careful assessment is required on case by case basis in order to determine the most appropriate strategy.
New guidance from EPO expected
Through our close-working with the EPO, we have become aware that EPO Examiners have been given new internal guidance on amending the description into conformity with the claims, and it is expected that updates on practice will appear in the March 2021 revision of the EPO Guidelines.
Some of the more established and more formal sides of amending the description do not look set to substantively change. The main changes we are aware of so far appear to relate to how subject-matter that falls outside the allowed claims or is excluded from patentability should be dealt with (see boxes below).
Embodiments not covered by the claims
All embodiments which are not covered by the claims anymore must be deleted, unless these embodiments can reasonably be considered to be useful for highlighting specific aspects of the amended subject-matter. In such case, they must be prominently marked as not being part of the present invention (T 1808/06):
- [For example, independent claim <X> has been amended by limiting it to the feature of <feature A>. Ways of carrying out the invention using features presented as alternatives to this feature must either be deleted or the fact that they are not encompassed by the claims must be prominently stated.]
- [Any combinations of features which do not fall under the scope of the amended independent claims must be prominently marked as not being part of the present invention. For example, amended claim <X> comprises features <A>, <B> and <C> and the description on page X refers only to B+C as an embodiment of the invention. It must be marked as not being part of the invention.]
- [Statements such as “The following examples/aspects/embodiments X, Y, Z are not according to the invention and are present for illustration purposes only” may be used at the start of the description (or in the list of figures) when such a situation arises.]
At first sight, the new requirements stated by the EPO appear relatively straightforward and are rooted in existing EPO Technical Board of Appeal case law. The overriding message is that all embodiments which are not covered by the claims must be deleted, unless these embodiments can reasonably be considered to be useful for highlighting specific aspects of the amended subject-matter. In such case, they must be prominently marked as not being part of the present invention.
The examples outlined by the EPO (box above) relating to marking embodiments as not being part of the claimed invention, appear to relate to specific scenarios including (i) where a claim is narrowed to be directed to only one of a number of alternative embodiments originally claimed, or (ii) where a claim is narrowed to make a previously optional feature essential. Such scenarios might arise as a result of voluntary amendment or following a prior art or unity objection. An example of the former could relate to a claim originally reciting a mono- or di-galactoside that is amended during prosecution to recite only di-galactosides. There will be subject-matter in the description relating to mono-galactosides which arguably falls outside the normal meaning of the amended claim. On the latter, making a previously optional feature essential can take many guises, such as incorporating an entirely new element into the claim (as in, for example, amending an originally claimed mono-therapy to a combination therapy) or reciting additional properties, features or even parameters of an existing feature (such as incorporating the diameter or zeta potential of a claimed nanoparticle or reciting a modification pattern on a claimed siRNA molecule).
Even for these scenarios, it is understandable that Applicants might be reluctant to delete such passages now apparently falling outside the normal meaning of the amended claim and also reluctant to explicitly state that certain subject-matter is outside the scope of the claims. Both options might have implications in other jurisdictions which do not have prosecution estoppel as well as potentially any equivalence argument the Applicant might wish to later rely on. Taking a simple example of equivalence, in a situation where a chemical group in a molecule has been narrowed to specify a particular element from a list of possibilities, is it more preferable for the Applicant to delete all of the other alternatives from the description or to ‘prominently mark’ that they are not part of the invention?
Further, given that the language proposed by the EPO to ‘prominently mark’ subject-matter is positive in explicitly reciting which embodiments are not according to the invention, it is doubtful that amending ‘embodiment’ to ‘instance’, or ‘invention’ to ‘disclosure’ (either on a passage by passage basis or on a blanket basis) will be sufficient under the new Guidelines to ‘prominently mark’ subject-matter as not being part of the present invention. In fact, many EPO Examiners are now including an explicit statement to this effect in Examination Reports.
Other, and potentially more complex, scenarios can also be envisaged where it is less clear is how it might be possible to ‘prominently mark’ subject-matter as not being part of the present invention.
For example, if a description was originally drafted as referring to an ‘antagonist of antigen X’ and the claims were later amended to recite ‘an anti-X antibody’, it is likely that very few passages of the description would relate specifically to the anti-X antibody. Instead, the description would likely be littered with individual sentences/ paragraphs of the description that still “highlight specific aspects of the amended subject-matter” (such as referring to aspects of therapeutic or diagnostic use), but which are strictly “not covered by the claims” because they use the generic term ‘antagonist of antigen X’ and not the specific term ‘antibody’.
Again, it is understandable that Applicants would be reluctant to delete such passages because of their potential use in still defining helpful or even important aspects of the invention as claimed, but there is currently less explicit guidance as to how to ‘prominently mark’ this subject-matter as not being part of the present invention, or indeed whether any amendment to such passages even is required. Based on the suggestion in (c) in the box above, an overarching statement at the beginning of the description might be considered as sufficient to ‘prominently mark’ if appropriate language could be crafted. Alternatively, each passage might be marked as not being part of the present invention.
Of course, the Guidelines cannot cover every eventuality, however it does appear that in practice, especially in the life sciences area, the new requirement to ‘prominently mark’ might not be straightforward to implement. Careful consideration of the appropriate strategy to take will be required on a case-by-case basis.
Exclusions from patentability
Subject-matter in the description being excluded from patentability under Article 53 EPC needs to be excised, reworded such that it does not fall under the exceptions to patentability or prominently marked as not being according to the claimed invention.
As for embodiments not covered by the claims, particular considerations also apply to dealing with subject-matter excluded from patentability. Many specifications in the life sciences field having medical use claims (e.g. EPC 2000 purpose-limited product claims) will have sentences/paragraphs relating to excluded subject-matter, such as methods of treatment.
As discussed above, it is understandable that Applicants would be reluctant to delete such passages as they are highly likely to be useful for highlighting specific aspects of the amended subject-matter, but there is currently less explicit guidance as to how to ‘reword’ or ‘prominently mark’ this subject-matter as not being according to the invention. Again, potential added-matter as well as claim interpretation post-grant will need to be carefully considered.
Why is this all important?
This is a question that we are often asked by our clients. In some cases, the description can be crucial for interpreting the claims and so amendments made to the description can play an important role in determining the scope of the claims.
As a cautionary tale, we have successfully argued post-grant in EPO Opposition proceedings that a claim feature should be interpreted as having a particular meaning, based on an unamended passage of the description. The Opposition Division considered this feature, when interpreted in this way in the light of the description, to add subject-matter and, consequently, the patent was revoked.
One can also imagine that a pitfall to amending a description on a ‘blanket’ basis in combination with a newly introduced overarching statement relating to what subject-matter is outside the scope of the claims is that it is left to the reader (at least to some extent) to decide what passages should be excluded. There are obvious advantages and disadvantages to this approach with respect to claim interpretation.
Of course, beyond the EPO, a further consideration is of course how national courts might view any amendments that have been introduced, especially with a view to the recent jurisprudence introducing a doctrine of equivalents into UK law.
A further layer of complexity is perhaps the recent obiter approval by Arnold LJ sitting in the UK High Court of the established jurisprudence in the Bundesgerichtshof (German Federal Court of Justice), whereby if a Patentee discloses embodiments of the invention that are subsequently not claimed, then they should not be considered to be encompassed by the claims on either a literal or equivalence basis. An important consideration therefore is perhaps the balance of Arnold’s ‘disclosed but not claimed is disclaimed’ approach with the UK court’s reluctance to delve into the file history of a case.
This is a rapidly developing area of EP practice, which will likely affect a number of other areas of our practice, such as how we draft specifications or the types of arguments that centre around claim interpretation that might be worth pursuing during EPO Opposition or Appeal.
Based on our experience and also having spent time speaking to EPO Examiners since issue of their internal guidance, we have assembled a ‘toolbox’ of strategies for amending a description in advance of the official release of the new Guidelines. There are, of course, pros and cons for each approach, but what is clear is that there can be high risks associated with adopting a one-size-fits-all approach to amending a description. Different considerations might apply on a case by case basis as to claim interpretation or even national considerations, should these be considered to be of particular relevance.
The patent attorneys at CMS are skilled in this area and CMS also has a team of patent litigators in UK, France and Germany who are on hand to advise.
 EPO Guidelines F-IV, 4.3
 EPO Guidelines F-II, 4.2 & 4.5
 Legal basis cited is EPO Board of Appeal decision T 1808/06 (see Case law of the Boards of Appeal of the EPO book (9th edition, July 2019), chapter II-A section 5.3).
 Article 69 EPC & Protocol on the Interpretation of Article 69 EPC
 Eli Lilly v Actavis UK Ltd & Ors  UKSC 48 (12 July 2017)
 Akebia Therapeutics Inc v Fibrogen, Inc  EWHC 866 (Pat) (20 April 2020)