INFORMATION FROM THE CONTRACTING / EXTENSION STATES
Decision of the Bundespatentgericht (Federal Patent Court) - dated 25 August 1997
(20W (PAT) 31/96)*
Headword: Steuerbare Filterschaltung (Controllable filter switch)
Section 59, 21(1)(4), 22(1), 38 PatG (Patent Law)
Keyword: "Extent of protection conferred by a patent - no inadmissible extension of protection by deleting originally non-disclosed features in claims during opposition proceedings - Limitation of claims to scope of original disclosure takes precedence over prohibition on later extension of protection"
Under PatG 1981, as under previous legislation, a feature in a patent claim which was not disclosed in the original patent application documents as belonging to the claimed invention may be deleted in opposition proceedings. The resulting amendment does not constitute an extension of protection under Section 22(1), second alternative PatG, which would already be inadmissible in opposition proceedings (following BGH GRUR 1977, 714 - "Fadenvlies"; 1975, 310 -"Regelventil"; 1990, 432 - "Spleisskammer". Contrary to BPatG GRUR 1990, 114 - "Flanschverbindung"; BlPMZ 1991, 77 - "Elektrischer Kontaktstift"; 1990, 431 - "Gestellmagazin").1
From the reasons
1. The German Patent Office (...) revoked patent No. 29 38 994 in response to an opposition based solely on the allegation that the subject-matter of the patent extended beyond the content of the application as filed (...), after the patent proprietor had left the text of its patent unchanged.
In appeal proceedings, the patent proprietor seeks a decision to maintain the patent as granted. Auxiliarily, it submits two new versions of claim 1 during oral proceedings.
The patent proprietor requests that the impugned decision be set aside and the patent maintained as granted, and auxiliarily, that claim 1 be replaced by claim 1 according to auxiliary request I, (...) or, as a further alternative, that claim 1 be replaced by claim 1 according to auxiliary request II (...).
The patent proprietor argues essentially that the skilled person would have been able to infer from the original documents that the contested feature (...) belonged to the invention. At all events, it is possible to maintain the patent with a Schutzrechtsbeschränkungserklärung (footnote solution) according to the decision of the Federal Patent Court in "Flanschverbindung" (GRUR 1990, 114) (auxiliary request I) or (auxiliary request II) by replacing the contested feature with the measure which was indisputably disclosed, as under previous law (eg GRUR 1975, 310 - "Regelventil"). (...)
The opponent requests that the appeal be dismissed. It contests the main points of the patent proprietor's argument, and maintains that the text of the claim according to auxiliary request I is unclear and inconsistent and still contains the inadmissible feature, and that the text according to auxiliary request II is correct per se but inadmissible because it involves an extension of protection.
The claims 1 according to the main request (text as granted) and auxiliary request I (with "limiting declaration") are invalid, since their subject-matter extends beyond the content of the application as filed (Section 21(1) PatG). However, regarding claim 1 according to auxiliary request II, there is neither a ground for revocation (Section 21(1)(4) PatG) nor is there a broadening of scope within the meaning of Section 22(1), second alternative PatG (...).
1. Main request (...)
2. Auxiliary request I. Claim 1 according to auxiliary request I still contains the inadmissibly amending feature, albeit in conjunction with the appended statement (disclaimer) that this feature constitutes an inadmissible extension, which may be cited in proceedings against the patent proprietor. However, this statement does not lead to an allowable claim.
On several occasions, the Federal Patent Court and various commentators in the relevant literature have taken the view, referring to Section 22(1), 2nd alternative PatG, that a feature not originally disclosed in the patent claim cannot be deleted after grant, if the effect of deletion is to extend the protection conferred by the patent (see BPatG GRUR 1990, 114 - "Flanschverbindung"; and BPatG BlPMZ 1991, 77 - "Elektrischer Kontaktstift"; for utility model cancellation proceedings, BPatG BlPMZ 1990, 431 - "Gestellmagazin"; Benkard/Rogge, 9th ed., section 22, note 13; Benkard/Schäfers, 9th ed., section 38, note 43; Schulte, PatG, 5th ed., section 21, note 36; and Bernhardt/Krasser, Lehrbuch des Patentrechts, 4th ed., 438; see also the criticisms of Schwanhäusser in GRUR 1991, 165, 168.). According to this view, in order nevertheless to maintain the patent (in limited form), it is necessary in such a case to insert in the description a statement to the effect that the undisclosed feature constitutes an inadmissible extension from which no rights may be derived, but which may be cited in proceedings against the patent proprietor. A statement of this kind, occasionally referred to in the literature as a disclaimer or footnote solution, has been said to establish without amending the claims that this feature, on the one hand, is not part of the subject-matter of the protected teaching and is therefore not to be taken into consideration in the assessment of patentability, though on the other hand, the feature limits patent protection to those cases in which the same feature occurs (BlPMZ 1991, 77, 78 left-hand column, paragraph 2), so that the protection conferred by the patent is not extended.
The Court does not share this view. However, it does not agree with the reasoning of the Enlarged Board of Appeal of the EPO, which on the one hand has considered the insertion of a disclaimer to be incompatible with Article 69(1) EPC and on the other has ruled that, in the public interest, the conflict between the grounds for revocation under Articles 123(2) and 138(1)(c) EPC (inadmissible amendment of the patent) and Articles 123(3) and 138(1)(d) EPC (extension of protection) can only be resolved by revoking the patent (G 1/93, GRUR Int. 1994, 842, 844 - "Limiting feature"2), in so far as the feature not disclosed in the application as filed provides a technical contribution to the subject-matter of the claimed invention. Instead, the Court sees the following considerations as paramount:
(a) Under Section 21(2), second sentence, PatG, it is possible in principle to effect the limitation of a patent by amending the description or the drawings. However, it appears doubtful whether a clearly worded claim is in fact open to interpretation using the description under Section 14 PatG in the way intended ("no" in decision G 1/93 of the Enlarged Board of Appeal of the EPO, GRUR Int. 1994, 842, 844, point 141). The question does not require exhaustive discussion here, since in the present case the patent proprietor has not inserted the intended limitation ("this feature constitutes an inadmissible extension, which may be cited in proceedings against the patent proprietor") in the description but in the patent claim itself (...).
(c) The Court shares (...) the opponent's view that the statement inserted in claim 1 (...) does not remove the inadmissible amendment, since the statement neither suffices to prevent the legal consequence provided for in Section 21(1)(4) PatG, according to which the patent is to be entirely or partly revoked, nor can it prevent the patent proprietor from deriving rights from the undisclosed feature.
(aa) Even if, as is intended by inserting the disclaimer, the inadmissible amendment in the claim were not taken into consideration in the substantive examination of the patent and if, to this extent, the patent were to remain within the scope of the original disclosure, the extending feature would nevertheless in the event of infringement take on precisely the legal significance which the limitation is designed to remove. Since the inadmissible feature may be cited in proceedings against the patent proprietor, he could only claim rights on the basis of this feature together with others (see eg Benkard/Rogge, 9th ed., section 22, note 13; BPatG BlPMZ 1991, 77, 78 - "Elektrischer Kontaktstift"), so that the feature is precisely not removed but remains in the patent claim, in contravention of Section 21(1)(4) PatG and Section 38, last sentence, PatG.
The patent proprietor itself has said (...) that it wishes the additional statement according to auxiliary request I to be seen in these terms. Its interpretation of the disclaimer conforms with the aforementioned jurisprudence of various Senates of the Federal Patent Court (BPatG GRUR 1990, 114 - "Flanschverbindung"; BPatG BlPMZ 1990, 43 - "Gestellmagazin"; BlPMZ 1991, 77, 78 left-hand column - "Elektrischer Kontaktstift"), which, however, does not escape the dilemma of having to revoke the patent on the basis of either Section 21(1)(4) or Section 22(1), second alternative PatG (on this issue, see also Rübel, VPP-Rundbrief 4/1995, 108, 110 left-hand column). The disclaimer is worded in such a way that no protected matter would remain if, in infringement proceedings (...), there were no possibility of deriving rights from the inadmissible feature but on the other hand this feature were cited against the patent proprietor ("which may be cited in proceedings against the patent proprietor"). Consequently, despite the disclaimer, the feature which was not originally disclosed and has remained in the claim continues to play a part in defining the claimed subject-matter, which therefore extends beyond the content of the application as filed, with the result that the legal requirements in respect of the ground for revocation under Section 21(1)(4) PatG are still met.
(bb) Despite the conflict, arising from the deletion of the inadmissible feature, with Section 22(1), second alternative PatG, which already prohibits the broadening of the scope of the patent at the opposition stage (BGH GRUR 1990, 432, 433 - "Spleisskammer"), it remains the case - following the jurisprudence of the Federal Court of Justice from the previous law (BGH GRUR 1975, 310 - "Regelventil"; 1977, 714 - "Fadenvlies") - that an amendment which plays a part in defining the subject-matter of the patent must be removed if it becomes apparent that the amendment extends beyond the content of the application as filed. If the feature is not deleted, the patent must be revoked.
This follows not only from the history of the ground for revocation in Section 21(1)(4) PatG but also from a restrictive interpretation of Section 22(1), second alternative PatG in view of the latter's intention and purpose. By providing that no rights may be derived from amendments or corrections which broaden the subject-matter of the application, the 1968 Patent Law (Section 26(5), second sentence; now Section 38, second sentence) already sought to rule out any possibility that a patent might be granted with inadmissibly amended subject-matter (BGH GRUR 1975, 310, 312 left-hand column, paragraph 1 - "Regelventil"). Under previous law, this provision was also applied where the patent had been granted with an extension (Amtliche Begründung [Official commentary] PatG 1978, BlPMZ 1976, 264, 334 right-hand column, re No. 9). There was no intention of changing this legal position when the grounds for revocation were amended in PatG 1978, since the introduction of a corresponding ground for revocation, and the possibility thereby established of removing once and for all the appearance of legality created by the grant of the patent, was seen as desirable by the legislator, for reasons inter alia of legal clarity and legal certainty (Amtliche Begründung PatG 1978, loc. cit).
However, following the amendment of the grounds for revocation, the legislator considered it necessary to amend the grounds for opposition accordingly (Amtliche Begründung PatG 1978, BlPMZ loc. cit., 335 left-hand column, re No. 13) and, with the introduction of the post-grant opposition procedure in PatG 1981, to raise the ground for revocation of inadmissible extension under Section 13(1)(4) PatG 1978 to the status of a ground for nullity. The importance of the latter is not weakened by the simultaneous introduction of inadmissible extension of the scope of protection as a ground for nullity under Section 22(1), second alternative PatG; instead, it is merely supplemented in order to include those extensions which, because of the amended opposition procedure, are no longer covered by the ground of inadmissible extension under Section 22(1), first alternative in conjunction with Section 21(1)(4) PatG (Amtliche Begründung PatG 1981, BlPMZ 1979, 266, 281 right-hand column, re No. 12, in conjunction with Amtliche Begründung PatG 1978, loc. cit., 335 left-hand column, paragraph 2). This new arrangement affects those cases in which the granted claims have been extended but the extension does not go beyond the content of the application as filed. By contrast, where an extension - if the case arises, a belated extension - goes beyond the scope of the original disclosure, the previous legal position, according to which the inadmissible feature must be removed in consequence of Section 38 PatG and in the interests of legal certainty, must continue to apply (BGH GRUR 1975, 310 - "Regelventil"). In the present case, however, the inadmissible feature has remained in claim 1 according to auxiliary request I; the request therefore had to be refused.
3. Auxiliary request II. Claim I according to auxiliary request II does not contain the inadmissible feature. The latter has been deleted and replaced by the feature of controllability of the limit frequency by means of the stabilised current regulator, which is indisputably derivable both from the original application documents and from the later patent documents as belonging to the claimed invention (see II.1.a above). The Court considers these amendments made by the patent proprietor to be admissible and finds that claim 1 according to auxiliary request II is allowable.
(a) The Court nevertheless acknowledges that the deletion of a feature from a claim normally involves an extension of patent protection, just as each additional feature will limit the scope of the protected matter. Under Section 22(1), second alternative PatG, such an extension of protection constitutes a ground for revocation which already has to be considered in opposition proceedings (BGH GRUR 1990, 432 - "Spleisskammer"). However, interpreting this provision in teleological terms and having regard to its history, the above consideration applies only (...) to those cases where an extension of protection occurs during post-grant opposition proceedings and remains within the scope of the original disclosure. Under previous law, it would have been impossible to oppose such an extension of protection - now inadmissible - once the patent had been granted, since the only ground for revocation mentioned in the former Section 13(1)(4) PatG (now Section 21(1)(4)) was the extension of the scope of the original disclosure (see Amtliche Begründung PatG 1981, BIPMZ 1979, 281 right-hand column, re No. 12). However, as was explained in the Amtliche Begründung (loc. cit.), this conflicts with the principle, established in the European Patent Convention and in existing [German] law, that the public should be able to assume that the protection conferred by a patent will not be extended after the patent has been granted.
If the sole purpose of introducing the ground for revocation under Section 22(1), second alternative PatG was to close the above-described gap resulting from the introduction of a post-grant opposition procedure, then there is no reason to interpret this provision as separate from and independent of the provision of Section 21(1)(4) PatG and to apply it also where the subject-matter of the patent is to be limited to what was disclosed in the original application documents. To this extent, following the legislator's intention and in order to avoid the paradoxical, inappropriate and therefore unintended result of revocation of the granted patent (regarding the position under the EPC, see the decision of the EPO Technical Board of Appeal in T 231/89 "Flat torsion spring" - OJ EPO 1993, 13, 16) the earlier legal position should remain unchanged, so that, in these cases, adherence to the scope of the original disclosure takes precedence over the ground for revocation under Section 22(1), second alternative PatG, since the deletion of a feature not disclosed in the original documents is not considered to constitute an extension of protection - which is already inadmissible in opposition proceedings - under Section 22(1), second alternative PatG (following BGH GRUR 1975, 310 - "Regelventil"; and 1977, 714 - "Fadenvlies").
(b) This is not contradicted by the fact that the inadmissible feature is no longer deleted during the grant procedure but, since the introduction of the post-grant opposition procedure, after the patent has been granted. The post-grant opposition procedure also serves the purpose, albeit within the framework of the legal grounds for revocation, of finalising the form of the patent, which often involves the amendment of claims (see BGH GRUR 1989, 103 - "Verschlussvorrichtung für Giesspfannen"). For this reason, amendments, including deletions which limit the subject-matter of the patent to the content disclosed in the original application, are to be communicated to the public, applying Section 61(2) and (3) PatG mutatis mutandis, in the Patent Gazette and by publishing an amended patent specification.
(c) Finally, the deletion of the inadmissible amendment - unlike the insertion of a disclaimer in the broadened claim - is not only in line with the legislator's thinking in introducing the ground for revocation in Section 22(1) second alternative PatG; it also offers a means of resolving, in a mutually satisfactory way, the tension between this provision and Section 21(1)(4) PatG and the attendant conflict between, on the one hand, the individual interest of the inventor in deleting only the inadmissibly extending feature where the patent is otherwise maintained, and on the other, the interest of third parties and of the public in the complete removal of the appearance of legality created by the grant of the patent. The inventor is appropriately rewarded for his work, and at the same time the public interest in deleting the inadmissible amendment (...) is sufficiently acknowledged.
(d) It is up to the infringement courts to decide how to protect the interests of the person whose action affects the extent of protection which is then amended as a result of the deletion (see BGH GRUR 1970, 296 - "Allzweck-Landmaschine"; and 1975, 310, 312 left-hand column - "Regelventil"). The relevant legislation offers various examples of a satisfactory balance between the interests of the person who has begun to use an invention on the basis of assumptions made in good faith about the extent of protection derivable from the patent claims, and the interests of the patent proprietor, whose rights are adversely affected by the deletion of the inadmissible feature. Thus, for example, the Community Patent Convention protects the rights of a person who assumes in good faith that the translation of a patent is accurate, by granting him a continued right of use if his use of the invention has, as a result of the correction of the deficiencies in the translation, infringed the linguistically amended patent (Article II, Section 3(5) Law on International Patent Treaties; see also Schwanhäusser, GRUR 1991, 165, 169), and Section 123(5) PatG protects the position of a person who has in good faith exploited the subject-matter of a lapsed patent which, as a result of reinstatement, has re-entered into force, by granting a continued right of use. The Extension Law also confers a right of continued use on a person who has begun to use the protected invention in the territory where the title did not previously apply (Section 28). Further examples are to be found in the Copyright Law (...). Section 137(f)(3) and (4) Copyright Law lays down rules for dealing with use which began before the entry into force of the Law and affects rights resumed thereby. According to these provisions, use which began before the date of entry into force may be continued, but only on payment of equitable remuneration, whereas use which took place before this date is not subject to such payment. This Court is not required to decide what solution would ultimately be appropriate to the present case.
* Official text of the decision, abridged for publication. Reasons published in full in Mitt. 1998, 221, BPatGE 39, 34.
1 See also the decision of the Federal Patent Court in "Zerkleinerungsanlage" dated 9 January 1998 - Mitteilungen der deutschen Patentanwälte 1998, 220.