G 0001/93 - Limiting feature / The "inescapable trap" - #6

Citation rank: 6
No. of citations: 258

G 1/93 deals with the conflicting requirements of Art. 123(2) and (3), and with the harsh consequences that an undetected violation of Art. 123(2) during examination can have on the patentee.

Art. 123(2) holds that a patent application or patent may not be amended in such a way that it includes subject matter which goes beyond the content of the application as filed. Art. 123(3), on the other hand, holds that a patent may not be amended such that its scope of protection is extended.

In the underlying case, the applicant filed, upon prosecution, amended claims which included a limiting feature going beyond the content of the original application. The Examining Division failed to spot this. Hence a patent was granted despite a violation of Art. 123(2). The patent was opposed and the opponent raised, i.a., the ground of Art. 100(c) (extension of subject matter). The Opposition Division accepted that submission and revoked the patent. The proprietor appealed against that decision.

Upon appeal, the Technical Board considered the principal relationship between paragraphs 2 and 3 of Article 123 EPC. They noted that in such cases where an unallowed amendment is made in examination by introduction of an undisclosed limiting feature, but a patent was nevertheless granted on the amended claim, such limiting feature could in principle not be removed in opposition without violating Art. 123(3). The Technical Board found this situation somewhat unsatisfactory, because was a rather harsh consequence of an error, which was - after all - also not spotted by the Examining Division. The Board thus referred the following question to the Enlarged Board of Appeals:

 "If a European patent as granted contains subject-matter which extends beyond the content of the application as filed and also limits the scope of protection conferred by the claims, is it possible during the opposition proceedings to maintain the patent in view of paragraphs 2 and 3 of Article 123 EPC?"

The Enlarged Board looked a previous case law regarding this matter. They noted that insofar as in these cases the Boards of Appeal have found support in the original applications for replacing added undisclosed technical features by other features without violating Article 123(3) EPC, they seem to be uncontroversial. They also found that it was never disputed that an added undisclosed feature without any technical meaning may be deleted from a claim without violating Article 123(3) EPC. The situation addressed the referred question (where the added feature had technical meaning, i.e., a limiting character), however, was still not fully clarified by case law.

The Enlarged Board found that both Art. 123(2) and 123(3) have mandatory character and that paragraphs 2 and 3 of Article 123 EPC are mutually independent of each other. They stated:

"Thus, if a limiting feature is considered to fall under Article 123(2) EPC, it cannot be maintained in the patent in view of Article 100(c) EPC, nor can it be removed from the claims without violating Article 123(3) EPC. Only if the added feature can be replaced by another feature disclosed in the application as filed without violating Article 123(3) EPC, can the patent be maintained (in amended form). [...] In this sense, it must be admitted that Article 123(2) in combination with Article 123(3) EPC can operate rather harshly against an applicant, who runs the risk of being caught in an inescapable trap and losing everything by amending his application, even if the amendment is limiting the scope of protection." (point 14 of the reasons)

In some cases, however, where the undisclosed feature (while having a limiting effect on the scope of the claim) makes no technical contribution to the invention, the Enlarged Board found that the limiting feature may remain in the claim without infringing Art. 123(3). They stated:

"If such added feature, although limiting the scope of protection conferred by the patent, has to be considered as providing a technical contribution to the subject-matter of the claimed invention, it would, in the view of the Enlarged Board, give an unwarranted advantage to the patentee contrary to the above purpose of Article 123(2) EPC. Consequently, such feature would constitute added subject-matter within the meaning of that provision. A typical example of this seems to be the case, where the limiting feature is creating an inventive selection not disclosed in the application as filed or otherwise derivable therefrom. If, on the other hand, the feature in question merely excludes protection for part of the subject- matter of the claimed invention as covered by the application as filed, the adding of such feature cannot reasonably be considered to give any unwarranted advantage to the applicant. Nor does it adversely affect the interests of third parties (cf. paragraph 12 above). In the view of the Enlarged Board, such feature is, on a proper interpretation of Article 123(2) EPC, therefore not to be considered as subject-matter extending beyond the content of the application as filed within the meaning of that provision. It follows that a patent containing such a feature in the claims can be maintained without violating Article 123(2) EPC or giving rise to a ground for opposition under Article 100(c) EPC. The feature being maintained in the claims, there can be no violation of Article 123(3) EPC either." (point 16 of the reasons)

In other words, the Enlarged Board confirmed that an "inescapable trap" generally exists between Art. 123(2) and (3), but that in cases where the violating feature makes no technical contribution to the invention, an inescapable trap situation is not present.

Remark: G 1/93 in principle distinguishes between technical features, which make a technical contribution and those which do not. This concept has later been used by the Enlarged Board in G 1/03, G 2/03 when considering admissibility of undisclosed disclaimers (see here for a brief summary of G 2/03).

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Headnote:

1. If a European patent as granted contains subject-matter which extends beyond the content of the application as filed within the meaning of Article 123(2) EPC and which also limits the scope of protection conferred by the patent, such patent cannot be maintained in opposition proceedings unamended, because the ground for opposition under Article 100(c) EPC prejudices the maintenance of the patent. Nor can it be amended by deleting such limiting subject-matter from the claims, because such amendment would extend the protection conferred, which is prohibited by Article 123(3) EPC. Such a patent can, therefore, only be maintained if there is a basis in the application as filed for replacing such subject-matter without violating Article 123(3) EPC.

2. A feature which has not been disclosed in the application as filed but which has been added to the application during examination and which, without providing a technical contribution to the subject-matter of the claimed invention, merely limits the protection conferred by the patent as granted by excluding protection for part of the subject-matter of the claimed invention as covered by the application as filed, is not to be considered as subject-matter which extends beyond the content of the application as filed within the meaning of Article 123(2) EPC. The ground for opposition under Article 100(c) EPC therefore does not prejudice the maintenance of a European patent which includes such a feature.

The full text of G 1/93 can be found here.

T 0190/99 - Claims read by a "mind willing to understand" - #41

Citation rank: 41
No. of citations: 109

T 190/99 is famous for its statement that a patent claim must be "construed by a mind willing to understand not a mind desirous of misunderstanding" (cf. Headnote).

In the underlying appeal case the proprietor has amended claim 1 such that, if the original wording of claim 1 was interpreted literally, the amendment could be seen as extending the protection conferred over the one of the granted patent (Art. 123(3) EPC).

The invention related to a woven slide fastener, which included, i.a., "a plurality of binding warp threads (17, 18)", and "a plurality of tensioning warp threads (19)".

Original claim 1 required i.a.:

"the plurality of tensioning warp threads (19) extending parallel with and between said upper and lower binding warp threads (17, 18)".

When looking at the figures and the description (in particular Fig. 2 of the patent), it was immediately apparent that the tensioning warp threads 19 did not extend strictly parallel with (and between) the upper and lower binding warp threads 17, 18, as claimed. Instead, the tensioning warp threads 19 were arranged in some sort of a zig-zag pattern between parallel upper and lower binding warp threads 17 and 18.

Fig.2 of the patent (ref. numeral 19 added)

The patentee had filed an amendment by which the above claim feature was replaced by the following:

"each said tensioning warp thread (19) extending between adjacent upper binding warp threads (17,17) and between adjacent lower binding warp threads (18,18) in a plane parallel to planes in which the upper and lower binding warp threads (17,18) are disposed"

The appellant-opponent argued that the original claim feature unequivocally required parallel tensioning warp threads 19. The amended claim feature, however, now included embodiments in which the tensioning warp threads 19 were not strictly parallel to the upper and lower binding warp threads 17, 18, e.g., the feature now also covered the zig-zag pattern of the tensioning warp threads shown in Fig. 2. Art. 123(3) EPC would thus be infringed.

The Board, however, took a different stance. They considered that the literal interpretation of the original claim feature made little sense. They stated:

"2.2.3. It is of course part of the most basic knowledge of the skilled person that, in order to weave a fabric, the warp threads are arranged parallel to each other prior to inserting the weft thread. However in the finished fabric, e.g. a conventional plain weave fabric, each warp thread goes over one weft thread and under the next weft thread and so on. While the warp threads still appear to be parallel when the fabric is seen in plan, in cross section the warp threads can be seen to be running approximately sinusoidally in order to lock the warp and weft threads together. Thus the warp threads are not parallel in the strict sense of being equidistant straight lines.

2.2.4. Thus the skilled person, reading in claim 1 as granted that the tensioning [...] threads 19 [...] extend parallel with the upper and lower binding warp threads 17 and 18, would not unreservedly assume that "parallel" meant "parallel" in the strict geometrical sense of the word."

The skilled person would bear the description and drawings of the patent in mind when deciding what claim 1 as granted means. He would not adhere to the strict literal wording of the claim. Instead, he would would interpret the claim wording so that it makes sense:

"2.4. The board adds that the skilled person when considering a claim should rule out interpretations which are illogical or which do not make technical sense. He should try, with synthetical propensity i.e. building up rather than tearing down, to arrive at an interpretation of the claim which is technically sensible and takes into account the whole disclosure of the patent (Article 69 EPC). The patent must be construed by a mind willing to understand not a mind desirous of misunderstanding."

Applying these principles of interpretation, the amendment requested by the patentee was found not to infringe Art. 123(3) EPC.

The appeal was dismissed.

Remark: T 190/99 is sometimes used by applicants in response to clarity objections; the argument being that a "mind willing to understand" would be able to make sense of the claim wording, thus Art. 84 would not be infringed. I find that a distinction must be made between opposition cases (in which the possibilities of amending a claim are restricted Art. 123(3) EPC and cannot be contested under clarity, and examination proceedings (in which the claim language can be changed more freely). The Headnote of T 190/90 should not be over-streched and used as a justification for unclear or inconsistent claims upon examination.

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Headnote:

The skilled person when considering a claim should rule out interpretations which are illogical or which do not make technical sense. He should try, with synthetical propensity i.e. building up rather than tearing down, to arrive at an interpretation of the claim which is technically sensible and takes into account the whole disclosure of the patent (Article 69 EPC). The patent must be construed by a mind willing to understand not a mind desirous of misunderstanding. 

The full text of the decision can be accessed here.

Quotes from 10 random decisions citing T 190/99 can be found here.