What amendments are permissible in order to be in line with the requirements under Article 123(2) and (3) EPC?
Chair: Manfred Vogel (AT)
Member of the Legal Board of Appeal, European Patent Office
What amendments are permissible in order to be in line with the requirements under Article 123(2) and (3) EPC?
I. Balance between freedom of the applicant/patentee and protection for third parties
Ladies and gentlemen,
I'm glad to have the opportunity to try to present the relevant issues under Article 123 EPC from the perspective of the boards of appeal. The narrow timeframe and the broad topic urge me to focus on general principles – which can be a good thing, because these principles tend to be forgotten sometimes amidst extensive discussions on specific aspects such as disclaimers, etc.
Article 123, "Amendments", forms part of Part VII ("Common provisions") of the Convention. Its first paragraph ensures that amendments may be made at all to applications after their filing, and it refers to the Implementing Regulations. The other two paragraphs are not merely of a formal or procedural nature, as we will see.
In practice, most amendments are made to the claims of a patent or patent application. Such amendments may be necessary to comply with formal requirements, such as the provision in Article 84 EPC relating to clarity and conciseness of the claims. However, most amendments to patent claims are made in order to distinguish or further distinguish the subject-matter from the prior art. This has to be kept in mind when it comes to the allowability of amendments.
As to the practical relevance of Article 123 EPC, I would like to quote just one figure. In the public database of decisions of the boards of appeal, 449 decisions were published last year in which either Article 123(2) or Article 123(3) EPC was cited as a legal basis; this is about 30% of all decisions. As it is not possible to give an overview of all the issues dealt with here and now, I would like to concentrate on some general principles.
2. Common goals of paragraphs 2 and 3
Looking at the wording, we see that paragraph 2 already applies to the patent application, not only to the granted patent. It sets a clear limit on the technical content of the patent application during its lifecycle: no technical content – which means technical information – may be added after the original filing date. On the one hand, this clearly limits the subject-matter to what the applicant had invented before he filed the patent application. On the other hand, any third party may conclude from the published original application how far the applicant might go in the final wording of his patent.
Paragraph 3 concerns the granted patent only. The scope of protection may not be extended after the patent has been granted. This rule primarily protects third parties. They can rest assured that after examination and grant the effects on third parties remain within the limits established by the granted patent.
Both limitations are so important that they may have effects throughout the lifecycle of a patent. The breach of either of the two rules in paragraphs 2 and 3 may lead to the invalidation of the patent – either in proceedings before the EPO or in national court proceedings.
II. Article 123(2) EPC as a limit on the technical content of an application
1. Principles developed in the case law of the boards of appeal
The basic question in assessing any amended wording in the claims or elsewhere is whether the technical teaching could be clearly and unambiguously derived from the application as originally filed. This formula conveys at least some good news: the wording of the amended application or patent is not limited to the literal wording of the original application. It is enough if the amended subject-matter can be derived from the original application by the relevant person skilled in the art. But – and this is a big "but" – the relevant teaching needs to be derivable in a clear and unambiguous manner from the original content of an application.
To explain the most relevant aspects of the magic formula "clearly and unambiguously", I would like to give a kind of schematic overview of a typical patent application. It contains the following elements:
- introduction/summary/abstract, summarising the most relevant aspects of an invention
- description of the relevant prior art (as far as known to the applicant)
- detailed description of the invention
- description of certain examples/ embodiments
- set of patent claims (generic independent claims and more specific dependent claims)
Every description or definition of a specific technical teaching consists of a limited number of technical features, which can be, for example, ingredients of a food product or cosmetic product, steps in a manufacturing process or components of a machine. Such features can be individual properties or numerical ranges; for specific features, there may also be a list of alternatives.
For specific subject-matter to be allowable in any amendment, all of its features have to be derivable clearly and unambiguously – in combination! – from the application as originally filed. This apparently simple rule may be infringed in various ways. In the following, I want to illustrate a number of patterns which are often disputed when it comes to examining a newly formulated patent claim under Article 123(2) EPC:
- No objections normally arise if a dependent claim is combined with the relevant independent claim.
- Generalisation of a definition: The omission of one or more features is normally not allowable if it is not entirely clear from the original application that the invention works without the specific feature(s). "Intermediate generalisation" is a term often used when a claim or generic description is supplemented with some but not all features of a specific example.
- Generalisation of a feature is critical. The replacement of "Diesel engine" by "combustion engine" introduces other combustion engines like Otto engines – which may or may have not been disclosed in the original application in the same context.
- "Mosaicking" a set of features from different parts of the description and/or from different claims is normally objected to because the original application did not show that the specific set of features may form a workable embodiment of the invention.
- Selections from a broader range may be made only under certain conditions. For example, a narrow range may be defined, taking the lower end of an originally disclosed broad range and the upper end of a preferred originally disclosed range – or vice versa.
- Selections from a list of alternatives are normally acceptable, as each alternative on the list is individually disclosed. However, if more than one selection needs to be made from lists or generic ranges, the result of the multiple selection is not considered to be within the range of the original disclosure. The term "singling out" is often used for such selections of specific teachings, which are not considered to be directly and unambiguously derivable from the original application.
In all these cases, where a newly introduced combination of features is objected to by the patent office or an opponent, the applicant or patentee has to convincingly argue why the skilled person could clearly and unambiguously derive the relevant teaching from the original application. In this context, not just logical arguments (set theory) must be considered but also the understanding of the relevant person skilled in the art – including the common general knowledge of this hypothetical person at the date of the application.
2. A typical example: dosage regime (T 612/09)
The invention relates to the dosage regime in the context of the treatment of patients with a known antibiotic, daptomycin. The original application referred to a preferred embodiment: 3 to 12 mg of daptomycin every 24 to 48 hours. In the course of the proceedings, the question arose whether the combination of a dosage of 3 to 10 mg and the interval of 48 hours was clearly and unambiguously derivable from the original application. The board of appeal came to a negative conclusion. In view of the principles set out above, this could not come as a surprise: the skilled person could not derive any sub-range of the originally disclosed dosage range, and the skilled person might have had doubts as to whether the lower dosage range could be combined with the upper end of the originally disclosed interval.
3. A systematic approach: who should get a patent?
This kind of case law – which might look strict sometimes– has to be considered in another context where the concept of "clearly and unambiguously disclosed" is used. Under the case law pertaining to novelty (under Article 54 EPC), an invention is considered novel if it has not been disclosed in a clear and unambiguous manner in the prior art. Some simple logical considerations may illustrate why the concept of clear and unambiguous disclosure has to be applied in the same manner under Article 123(2) EPC and when it comes to the question of novelty.
Let us use A for the original disclosure of a specific teaching and A' for the amended version, for example a definition where a numerical range has been limited to a narrower sub-range, or, as another example, the daptomycin dosage case just presented. A first application contains teaching A in its original version; later teaching A' is introduced into the same application. A second application containing A' in its original version is filed after the filing date of the first application but before A' is introduced into the first application.
If A' is considered to be directly and unambiguously disclosed within A, or, to put it another way, if A' is technically identical to A, the amendment of the first application would be allowed under Article 123(2) EPC, and teaching A' in the second application would face a novelty objection in view of teaching A in the first application. Only the first applicant would get a patent for A'.
If, on the other hand, A' is considered to be not identical to A (or not directly and unambiguously derivable from A), the amendment of the first application would not be allowed under Article 123(2) EPC, and teaching A' in the second application would be novel. Only the second applicant would get a patent for A'.
Under both assumptions, only the applicant who first introduces A' in his application has a chance to obtain a patent for A' – which is the only fair outcome in view of the "first-to-file" principle. Were the concept of "clearly and unambiguously disclosed" to be applied in different ways under Articles 54 and 123(2) EPC, the standard situation described would lead to difficult results:
- If A' is considered to be identical to A for the purposes of Article 123(2) EPC and not identical for the purposes of Article 54 EPC, the amendment of the first application would be allowed, and A' in the second application would be novel. Both applications could lead to a patent for A'.
- If A' is considered to be not identical to A for the purposes of Article 123(2) EPC and identical for the purposes of Article 54 EPC, the first application could not contain A' and the second application would face a successful novelty objection. Neither of the two applications could lead to a patent for A'.
In order to avoid such situations of "double patenting" or "zero patenting", application of the concept of "clear and unambiguous disclosure" needs to be the same under Articles 54 and 123(2) EPC. This means that novelty considerations can be used as a cross-check under Article 123(2) EPC. No teaching should be introduced into a patent or patent application which would be novel vis-à-vis the originally filed application.
It could be argued that this is a circular definition, defining "clearly and unambiguously" using "clearly and unambiguously" from another context. However, on the one hand, looking at novelty concepts opens a vast field of case law. On the other hand, keeping the disclosure criteria under Articles 54 and 123(2) EPC in line helps to avoid illogical outcomes.
III. Article 123(3) EPC as protection of third parties against extension of scope
1. Scope of protection delimited by the granting authority
Article 123(3) EPC is about the scope of protection conferred by a patent. Under Article 69 EPC, the scope of protection is primarily defined by the patent claims. Any alleged infringement falls within the scope of protection if it is covered by the wording of a claim, and that claim may need some interpretation. Interpreting the claims and determining the scope of protection is normally a task for the infringement courts. For this reason, the EPO has sometimes been reluctant to accept an amendment to a claim if it sees a risk that a national court, on the basis of national case law, could construe an amendment as an extension of the scope of protection. However, the Enlarged Board of Appeal held in an early decision (G 2/88) that the national laws of the contracting states relating to infringement should not be considered in the context of Article 123(3) EPC. Accordingly, the EPO could and had to develop a body of case law on the scope of protection in order to apply Article 123(3) EPC in a consistent and "European" manner.
If we look at this case law, we will find a number of decisions concerned with changes to claim categories. For example, a claim to a product may be converted into a claim to a specific use of the product. This amendment is acceptable because a product claim covers any use of a product. On the other hand, a claim to a manufacturing process for a specific product may not be converted into a claim to this specific product under Article 123(3) EPC because the product claim is broader, covering the product regardless of the manufacturing process leading to it.
2. Principles developed in the case law of the boards of appeal and a simplified example (T 2017/07)
For a set of other standard situations, I would like to refer to a simple example, which nevertheless can show that issues may get more complicated quite quickly. A simple patent claim to a food product could be worded as follows:
Food product, containing
- 30-60% yoghurt
- 5-10% sweetener
- up to 15% berries
In the course of opposition or limitation proceedings, several types of amendment may be made which may or may not be allowable:
- The deletion of a feature is normally not allowed, as it broadens the definition and the scope of protection. Deletion of the sweetener leads to a situation where products without sweetener are covered while these products were not covered by the patent as granted. This could severely affect any third party that produces unsweetened berry yoghurt.
- The generalisation of a feature regularly leads to the same problem. The replacement of "berries" by "fruit" means that apple yoghurt not containing any berries is covered after the amendment, while it was not covered before.
- The replacement of a feature by a narrow or more specific feature is normally not a problem as it further limits the scope of protection. Limiting the sweetener content to 5-8% means that a class of very sweet yoghurt is no longer protected under the claim.
In any case, the context of the feature and the whole meaning of the claim need to be considered. One possible limitation of the claim could be limiting the berries to strawberries. At first glance, this amendment narrows the definition and limits the scope of protection. On the other hand, the scope of the last condition becomes narrower – which could mean that the overall definition gets broader. A product containing 50% yoghurt, 10% sugar, 10% strawberries and 10% cranberries would not be within the scope of protection of the original claim because the berry content is above 15%. After the amendment, the same product would be covered by the claim because the strawberry content is less than 15% and the percentage of any other berries is no longer limited under the open claim. The situation would be different if the claim were not open, i.e. if the list of ingredients were exhaustive. Such lists are introduced by "consisting of" instead of "comprising".
In our case of an open definition, the limitation of "berries" to "strawberries" is not allowed because there is at least one embodiment which is covered only after the amendment of the granted claim. This is exactly the situation which Article 123(3) EPC seeks to avoid. For a post-grant amendment to fail under this provision, it is enough if one embodiment falls within the scope of protection after the amendment of the granted patent which did not fall within the scope of the patent when it was first granted.
IV. Conclusions: short answers to the questions in the title
If there are any short answers to the two questions in the title of this session, they could be worded as follows:
- An amendment is permissible under Article 123(2) EPC if the amended patent application or patent does not contain any subject-matter which would be novel vis-à-vis the application as originally filed.
- An amendment is permissible under Article 123(3) EPC if the scope of protection of the amended patent does not cover any embodiment which was not covered by the patent as granted.
But of course: the devil is in the detail. Let's work on the detail and at the same time remember some basic principles.
Thank you for your attention.
Date retrieved: 19 May 2021