Our partners and attorneys are highly qualified and highly experienced to advise you in all areas of Intellectual Property law. We advise start-ups, SMEs, and multinational corporations and ensure that your inventions, brands and designs are expertly protected.
Comma Conundrum: Avoiding Pitfalls in Patent Claims
Home / News & Articles / Comma Conundrum: Avoiding Pitfalls in Patent Claims
In Intellectual Property law, particularly for patents, precision in language and punctuation is crucial. If not used correctly, something as simple as a comma can lead to the loss of a patent.
A pertinent illustration of this is the EPO’s Board of Appeal decision T 1473/19 in which a missing comma in a claim led to an objection on added subject matter in opposition proceedings. This could not be rectified in the appeal proceedings without broadening the scope of the granted claim and fell into the “inescapable trap” of Article 123(2) and (3) EPC, which resulted in the patent being revoked.
This decision is a stark reminder of the importance of checking the text, including the amendments made by the examiner, which the EPO intends to grant, prior to approving the text in response to the Rule 71(3) EPC notification. The specific details of the case are discussed in detail below.
Background
In T 1473/19, an appeal was filed by the opponent against the Opposition Division’s decision to reject the opposition to the contested patent EP 2621341.
The respondent (patent proprietor) requested, that the patent be maintained as granted, or, as auxiliary measures, that the request for correction under Rule 139 EPC be granted, or that the patent be maintained in an amended form.
The contested patent relates to a contactless rotary joint for use, for example, in a CT scanner. Claim 1 of the patent describes a contactless rotary joint for a CT scanner, comprising a rotary joint body among other elements, and includes the following feature:
“said body having a free inner bore holding a capacitive data link”
The outcome of the case mainly hinged on the interpretation of this feature.
The respondent (patent proprietor) requested a correction under Rule 139 EPC to amend the above feature to:
“said body, having a free inner bore, holding a capacitive data link”
Missing comma and added subject matter
The opponent argued that the person skilled in the art, reading claim 1 as granted, would not have identified any ambiguity, and that they would have clearly and unambiguously understood from the expression in claim 1 “said body having a free inner bore holding a capacitive data link” that the body had a free inner bore and that this bore held a capacitive data link. The opponent further stated that this understanding of claim 1 was technically sensible and not illogical since a bore was not limited to an empty space but necessarily included a physical boundary, which was itself able to “hold” a capacitive link. They further argued that since claim 1 is clear, there is no need or justification to refer to the description to interpret the objected feature.
It was undisputed that a configuration where the body had a free inner bore and the bore held the capacitive data link was not disclosed in the application as filed.
The respondent (patent proprietor) argued that a person skilled in the art would have immediately identified an ambiguity in the expression objected to, and would have therefore consulted the description and the drawings to resolve this ambiguity to interpret the claims under Article 69 EPC, which was supported by established case law, for example, by T 131/15. They further argued that since the disclosure throughout the description showed the rotary joint body, and not the bore, held the capacitive data link, the person skilled in the art would have necessarily concluded that the objected feature of claim 1 could only be interpreted in this way.
Principles of claim interpretation
Since both parties disagreed on the principles of claim interpretation, it was necessary for the Board to interpret the claim in the following contexts:
– for the purposes of assessing whether it contains added subject-matter under Article 123(2) EPC;
– for the purposes of assessing whether it has been amended in the auxiliary requests in such a way that its extent of protection has been extended under Article 123(3) EPC.
The Board also noted that the two provisions in the EPC considered relevant to claim interpretation are Article 69 EPC and Article 84 EPC.
Article 84 EPC provides that: “The claims shall define the matter for which protection is sought. They shall be clear and concise and be supported by the description.”
Article 69 EPC provides that: “The extent of the protection conferred by a European patent or a European patent application shall be determined by the claims. Nevertheless, the description and drawings shall be used to interpret the claims.”
There are different views in the case law of the technical Boards of Appeal on the extent to which Article 69 EPC and the Protocol on the Interpretation of Article 69 EPC should be applied when interpreting patent claims.
In the present case, the Board considered both cases, which took the view that Article 69 is not applicable when determining added subject matter, and cases, which took the view that Article 69 is applicable when determining added subject matter.
In some cases such as in T 1279/04, the Board stated that the application of the principles of claim interpretation as laid down in Article 69 and the Protocol was limited to the determination of the extent of protection, which was primarily of concern in infringement proceedings. It further indicated that in examination and opposition proceedings before the EPO, Article 84, first sentence, provided a legal basis for applying “a strict definitional approach”.
The present Board noted that the main rationale underlying T 1279/04, seems to be that there is a difference between the subject-matter of a patent claim, which is determined in proceedings before the EPO and, the scope of the claims, which is determined under Article 123(3) EPC and in national infringement proceedings. While, the Board acknowledged a difference, it did not consider this difference a convincing reason not to apply Article 69 EPC when determining the claimed subject matter in proceedings before the EPO.
The Board also noted that this approach to claim interpretation is based on the principles set out in Article 69 EPC and the Protocol also serves the legitimate interests of the users of the European patent system, which includes the EPO opposition divisions and Boards of Appeal, the national courts and, soon, the Unified Patent Court.
Description and claim interpretation
The Board of Appeal noted there are divergent case law over the degree to which the description should be used to interpret the claims.
The Board noted that on the one hand in many decisions such as in T 1167/13 and T 2773/18 the description and the drawings have been used to interpret the claims and identify their subject matter. Whereas on the other hand, there is also a significant number of case law such as T 197/10 and T 1514/14 according to which the description and the drawings should only be used to interpret claim features which are ambiguous, and unambiguous terms in the claims should be interpreted without taking the description and the drawings into account.
In some cases such as T 1127/16 it has been stated that, for the purposes of assessing compliance with Article 123(2) EPC, the description and the drawings should not even be consulted in the case of ambiguous claim features.
Against this background, the Board had to take a view on whether or not the description should be used for claim interpretation. In line with some previous cases such as T 556/02, T 1646/12, T 2007/19, the Board agreed that patent claims must be interpreted in their context, which includes the description and adds that the description and the drawings provide context-specific information about the claimed subject-matter. Taking this information into account when interpreting a patent claim from the perspective of the person skilled in the art would make claim interpretation more accurate, which contributes to legal certainty; all the more so if, as is often the case, patentees use terms idiosyncratically in the claims.
The Board, however, added that although Article 69(1), second sentence, requires that generally an account be taken of the description and the drawings when interpreting a claim, the primacy of the claims according to Article 69(1), first sentence, limits the extent to which the meaning of a certain claim feature may be affected by the description and the drawings. Notably, the Board indicated that in the case of any discrepancies between the description and the claims, the ordinary meaning of the features in the claims should take precedence.
In the present case, the Board agreed with the interpretation of the appellant (the opponent) that, in the absence of any comma and any coordinating conjunction separating the various terms, the person skilled in the art, on a plain reading of this expression, would arrive at the construction that the body has a free inner bore and that this bore holds a capacitive data link and that there was no technical reason for the skilled person to depart from this interpretation. The Board of Appeal thus found no reason to depart from the normal meaning of the contested feature and the patent was revoked on the grounds of added subject matter.
The Board also noted that since the disputed expression of claim 1 was clear under the normal meaning a person skilled in the art would interpret it to mean that the free inner bore holds a capacitive link and therefore, amending the claim to indicate the rotary body holds a capacitive link would remove the limitation defined in claim 1 as granted that the free inner bore holds a capacitive link. Thus, the auxiliary requests were considered as not meeting the requirement of Article 123(3) EPC and not allowed.
Request for correction under Rule 139 EPC
The Board stated that Rule 139 EPC only allows correction of linguistic errors, errors of transcription and mistakes “in any document filed with the European Patent Office”.
The addition of the expression “having a free inner bore” in claim 1, was made by the Examining Division in the text intended for grant sent with the communication under Rule 71(3) EPC. The respondent (patent proprietor) approved the proposed text including this amendment. The Board took the view that this approval does not mean that the amendment was submitted by the respondent “in [a] document filed with the European Patent Office”. Thus, the requirement for a correction under Rule 139 EPC was considered as not met. Accordingly, the request for correction was refused at least for this reason alone.
Implications for Applicants and Attorneys
This case highlights that it is not only the choice of words that matter in patent claim interpretation, but grammar can be equally important.
The Board’s view on the interpretation of the claims is interesting, especially in light of the strict approach taken by the EPO in recent times, with respect to amendments of the description to be consistent with the allowed claims – For instance see T1024/18 (Amendments to the Patent Description: To what extent? Link)
It has long been the practice of the EPO to request applicants to amend the description to bring it into conformity with the allowed claims under Article 84 EPC. However, in the present decision T 1473/19, the Board appears to reject the view that Article 84 EPC is relevant to patent claim interpretation. The present Board notes that Article 84 EPC only defines the standard applied when assessing clarity, and thus appears to contradict the decisions supporting the description amendment requirement as justified by Article 84 EPC.
Also, a word of caution with respect to approval of text in response to the Notice of Intention to grant under Rule 71(3) EPC. In the present case the expression “having a free inner bore” in the contested feature in claim 1 was added by the Examining Division and was approved by the applicant. This decision is yet another reminder to applicants and patent attorneys to excises extra caution when approving the text in response to Rule 71(3) EPC notification, including any amendments by the examiner.
The Board of Appeal in T 1473/19 also made an interesting point on Rule 139 EPC that an approval of a text, including any proposed amendments by the examiner, in response to the Intention to grant notification does not fall within the meaning of “in [a] document filed with the European Patent Office”.
While, the Board indicated that Article 69 EPC should be used to interpret the claims, it is not fully clear as to why Article 69 and its Protocol should be considered when determining the presence of added subject matter under Article 123(2) EPC. We would need to watch out for more cases to see if the Boards of Appeal will continue to use Article 69 EPC to interpret claims when assessing whether or not the claims meet the requirement of Article 123(2) and 123(3) EPC.
Need Assistance?
If you would like to discuss any of the issues highlighted in this article, including patent drafting or oppositions, please contact Leonita or any of our Patent Attorneys for an initial discussion.
This website uses cookies so that we can provide you with the best user experience possible. Cookie information is stored in your browser and performs functions such as recognising you when you return to our website and helping our team to understand which sections of the website you find most interesting and useful.
The basics cookie, when enabled, means that we can save your preferences for the cookie settings panel and you won’t see the banner pop-up again unless you clear your browser’s cookie cache.
If you disable this cookie, we will not be able to save your preferences. This means that every time you visit this website you will need to interact with this panel again to enable or disable the cookies.
If you disable this cookie, we will not be able to save your preferences. This means that every time you visit this website you will need to enable or disable cookies again.
Analytics cookies
This website uses DoubleClick and Quancast to collect anonymous information such as the number of visitors to the site, and the most popular pages.
Keeping this cookie enabled helps us to improve our website.
Please enable Strictly Necessary Cookies first so that we can save your preferences!