Limits of a Limited Opposition

L. Walder-Hartmann (DE)

Part 2
This is part B of a long article. Part A was published in issue 02/2016 of the epi Information

The EPC requires a statement about the extent to which a patent is opposed (R. 76 (2) (c) EPC). If it is not the entire patent that is indicated in this statement, the opposition is understood to be a limited opposition. The way in which a limited opposition influences the examination of the opposition has been determined in more detail in the decision G 9/91 of the Enlarged Board of Appeal. However, not all case constellations have been considered. The question remains where exactly the limits of a limited opposition lie and if, and under which conditions, such a limited opposition may later be extended. To answer this question, an investigation into the nature of an opposition as well as a critical review of the reasons of the decision G 9/91 was the subject of a previous part A of this article. Based on the analysis of part A, the present part B of the article identifies the limits of a limited opposition and the conditions under which they can be pushed. The present part B seamlessly continues part A, thus starting with section III.

III. Examination Beyond the Extent to Which the Patent is Opposed

The principle of procedural fairness and the principle of procedural economy found in part A to determine the limits of limited opposition are applied here to answer the question where exactly the duty and power of the EPO to examine a limited opposition ends and under which conditions the extent to which the European patent is opposed can be changed later in the proceedings.

1. Amendment with a feature from the description

There is one trivial case in which examination (beyond the extent to which the patent is opposed) shall be carried out. Consider the example case again. If the patentee amends claim 1 with a feature from the description and requests maintenance of the European patent in this amended form then the opponent is free to oppose this amended form. The indication in the statement under Rule 76 (2) (c) EPC as to the extent of the opposition only refers to the claims as granted. If the patent is defended in some other form the opponent’s statement does not cover this situation, and, as is established practice in consideration of the new situation created by the patentee, procedural fairness dictates that the opponent can react to this new situation, and even perform a further search and introduce new facts and evidence relating to the amendment.

2. Examination of independent claims

Further, in direct continuation of the balance of interest established in the second part of the order of the decision G 9/91, there are cases in which examination may even be carried out on independent claims that were not included in the statement under Rule 76 (2) (c) EPC. Such a case is given if the independent claim is a claim for which novelty and inventive step need not be examined in grant proceedings if another independent claim is found allowable. Examples of such independent claims are given in the Guidelines for Examination in the EPO, G‑VII, 13, and include method claims for manufacturing a product or claims directed to the use of a product, where an allowable independent claim is directed to the product, provided the manufacturing method inevitably leads to that product. For instance, if claim 1 of the example case were directed to a product found allowable during prosecution, then claim 1 directed to “A manufacturing method, comprising providing the product of claim 1” would be such an independent claim, no matter if it contained further features or not.

Since such an independent claim is granted without further examination, just like regular dependent claims, it is justified that the Opposition Division shall also have the opportunity to examine such a claim if its validity is prima facie doubtful based on information already available in the proceedings.[1] For the example claim “A manufacturing method, comprising providing the product of claim 1” the validity is evidently not only doubtful if claim 1 is found invalid, but this claim is certainly invalid. Further, claims depending from such an independent claim may also be examined under the same conditions if a corresponding request to maintain the patent in amended form is put forth.

3. Consent of the patentee

In addition, the opposition can be extended, possibly up to the point where it becomes an unlimited opposition, if the patentee consents. The situation is analogous to what is said in Reason 19 of the decision G 9/91: volenti non fit iniuria, i.e., a person who consents does not suffer injustice. The distinction made in Reason 12 of the decision G 9/91 according to which the extent is a matter of formal competence while the introduction of new grounds of opposition are a question of procedural principles is unfounded as explained above. Both situations are governed specifically by the principles of procedural fairness and procedural economy. In practice, the opponent would have to invite the patentee to declare his consent which, if given, removes prior legal effects of the limitation of the opposition by the statement made in accordance with Rule 76 (2) (c) EPC. This means, inter alia, that substantive examination must be carried out by the EPO, and is not limited to be carried out on available information. The general rules of a regular, unlimited opposition apply. The EPO is not in a position to forestall this extension of the opposition, in particular because the opposition fee for a limited opposition is not less than the opposition fee for an unlimited opposition.

4. Intervention of an assumed infringer

The decision G 9/91 does evidently not consider the situation in which an assumed infringer intervenes into a limited opposition. The intervener becomes a party to the proceedings and shall be treated as an opponent (Art. 105 EPC). The question is if the intervener is subject to the limitations of the opposition imposed by the statement of the opponent according to Rule 76 (2) (c) EPC or if his opposition is an unlimited opposition unless indicated otherwise by the intervener.

If it were true that no opposition proceedings are in existence concerning non-opposed subject matters and if it were true that the EPO lacked the formal competence to decide on such matters once and for all after expiry of the opposition period one might be led to believe that the intervener would have to accept the opposition proceedings in the state that they are in, excluding the possibility to oppose these other subject matters. However, these assumptions are incorrect as explained above. The time limit set by the opposition period does not apply to the intervener in any case, and so any reasoning based thereon cannot hold for the intervener. The question has to be decided once again by the guidance of the principle of procedural fairness.

In this case, it is the patentee who creates a new situation by attacking the assumed infringer. If a claim asserted against the assumed infringer in the infringement proceedings belongs to those claims to which the extent of the limited opposition does not reach, a fair balance of the interests of the patentee and of the assumed infringer (intervener) shifts entirely towards protecting the interest of the assumed infringer to bring down the claims asserted against him as a means of defence. Even if the claims asserted against the assumed infringer are among those claims covered by the limited opposition, the assumed infringer (intervener) shall still be free to oppose the European patent in an unlimited way. There is no reason to restrict the possibility of defence for the assumed infringer to the choice made by the opponent. The situation and the interests are not different to the filing of a limited opposition by a first opponent and the filing of an unlimited opposition by a second opponent, resulting in opposition proceedings like any normal opposition proceedings resulting from a single unlimited opposition.

In summary, just as the intervener is not bound to the grounds of opposition set forth by the opponent,[2] he is also not bound by the extent to which the opponent opposed the patent in the statement made in the notice of opposition in accordance with Rule 76 (2) (c) EPC. His (unlimited) intervention shall be treated as an unlimited opposition.

That this is an appropriate result is further justified by the following consideration. In Germany, the contracting state with the highest number of European patents and European patent applications, invalidity of a patent cannot be claimed as a defence in infringement proceedings. Instead, nullity proceedings are separate proceedings dealt with by a special court, the Federal Patent Court. German law provides that an action for declaration of nullity of a patent may not be brought as long as opposition may still be filed or opposition proceedings are pending (Section 81 paragraph 2 of the German Patent Act).[3] There is a silent – and correct – assumption here that opposition proceedings always seize the whole patent as the matter in dispute. If one did not allow the assumed infringer to fully oppose a European patent if he intervenes into European opposition proceedings based on a limited opposition he would be left without the possibility to defend himself against “unopposed patent claims” asserted against him in Germany until such time when the European opposition proceedings are terminated.[4] With the possibility of the patentee to appeal, and possibly with a patentee trying to prolong the proceedings in any other way, the assumed infringer may be factually bereft of an effective defence in German infringement proceedings.

5. “Intervention” by an opponent to his own limited opposition

When an opponent filed a limited opposition, expressing his limited interest to attack the European patent, but the patentee changes the situation by suing this opponent, the opponent’s interest to attack the European patent to a larger extent will surge, and legitimately so. Then, the opponent shall not be bound to the limitation of the opposition. The situation and the balance of interests are analogous to the case discussed above when a third party is sued and becomes an intervener. There is no reason why the third party intervening in limited opposition proceedings should be in a better position than the opponent himself.

In practice, the opponent could not intervene into his own opposition proceedings under Art. 105 EPC because he cannot become a party to the proceedings twice. Instead, he should be allowed to prove that the conditions set forth under Art. 105 (1) (a) or (b) EPC are fulfilled, and then to extend his opposition freely.

This mechanism does not only work once. Assume that either the opponent extended his opposition, but not up to the point where it becomes unlimited, or else a third party intervener filed a limited intervention to be treated as a limited opposition, and then the patentee extends his infringement action. Again, it is the patentee who changes the balance of interest, and so the opponent or the intervener shall not be bound by the limitations of their opposition and intervention, respectively.

IV. Conclusion

An opposition, be it unlimited or limited, always seizes the entire European Patent. A limited opposition means, in the first place, a limitation of the duty and the power of the Opposition Division to examine an opposed European patent. Whether examination of granted claims lying outside the extent to which the patent was opposed according to the statement made by the opponent in fulfillment of Rule 76 (2) (c) EPC needs to be carried out, and if it can be carried out, is a question of exercise of discretion by the Opposition Division. The discretion of the Opposition Division in this matter is analogous to the discretion it has to exercise when deciding if opposition proceedings are to be continued of its own motion under Rule 84 (2) EPC. The discretion has to be exercised dutifully having regard to fairly balancing the interests of the parties in interest, i.e., the parties to the proceedings and the public, and having regard to procedural fairness and procedural economy. The limitation of the duty to examine is the lower bound of the scope of discretion (“abuse of discretion by doing too little”), and the limitation of the power to examine is the upper bound of the scope of discretion (“abuse of discretion by doing too much”). The statement of extent under Rule 76 (2) (c) EPC has further implications on the right to appeal (conditional waiver).

Following these principles the consequence is that granted claims not mentioned in the statement of extent shall in principle not be examined, be it as independent claims in the patent as granted or as independent claims in the patent as amended during opposition. Two exceptions apply. Firstly, such claims may be examined provided their validity is prima facie in doubt on the basis of already available information. The justification is given in this case by a predominant interest of the public. Examples are the examination of (pseudo-)independent claims in the patent as granted, and the examination of claims which formerly depended on an attacked independent claim and which are made the subject matter of an independent claim during opposition proceedings. Secondly, such claims may be examined if the balance of interests changes after expiry of the opposition period due to an action of the patentee. This action can be the patentee’s consent to extending examination. This action can also be an infringement action brought against the opponent or other assumed infringer who then intervenes in opposition proceedings. In the latter case, the opponent or intervener are free to oppose the patent to any extent.

This result fits in with the order of the decision G 9/91 if that order is carefully interpreted.

Das EPÜ erfordert eine Erklärung darüber, in welchem Umfang gegen das europäische Patent Einspruch eingelegt wird (R. 76 (2) (c) EPÜ). Falls nicht das gesamte Patent in dieser Erklärung angegeben wird, wird der Einspruch als beschränkter Einspruch verstanden. Die Art und Weise, in der ein beschränkter Einspruch die Prüfung des Einspruchs beeinflusst, wurde im Detail in der Entscheidung G 9/91 der Großen Beschwerdekammer festgelegt. Es bleibt jedoch die Frage, wo genau die Grenzen eines beschränkten Einspruchs liegen und ob, und falls ja unter welchen Bedingungen, ein solcher beschränkter Einspruch später erweitert werden kann. Um diese Frage zu beantworten, war eine Untersuchung der Rechtsnatur des Einspruchs und eine kritische Beleuchtung der Entscheidungsgründe der Entscheidung G 9/91 Gegenstand des Teils A dieses Aufsatzes. Aufbauend auf der Analyse des Teils A identifiziert der vorliegende Teil B des Aufsatzes die Grenzen des beschränkten Einspruchs und die Bedingungen, unter welchen sie verschoben werden können. Der vorliegende Teil B führt den Teil A nahtlos fort und beginnt daher mit Abschnitt III.

  1. Related: T 1350/09, reason 1 of the decision. Contrary to the case discussed here, the patent was formally opposed in its entirety in the case at hand in the decision T 1350/09.
  2. G 1/94, Order.
  3. BGH, BGHZ 163, 369, mn. 4 – Strahlungssteuerung; GRUR 2011, 848, mn. 9f. – Mautberechnung; Schulte/Voit, Patentgesetz mit EPÜ,. 9. Auflage, § 81 PatG, mn. 34ff.
  4. BGH, BGHZ 163, 369, mn. 6 – Strahlungssteuerung; GRUR 2011, 848, mn. 9 – Mautberechnung.