Center for Advanced Study & Research on Intellectual Property


CASRIP Newsletter - Spring/Summer 1997, Volume 4, Issue 2

Key Features of the European Patent Office (EPO) OppositionProcedures

This article briefly examines and highlights key features of theopposition procedure at the European Patent Office (EPO). Both the reexamination procedureunder U.S. law and the opposition procedure at the EPO provide third parties with theopportunity to contest the validity of an issued patent. However, what separates the roleof third party participation before the EPO from their role at the USPTO is the extent to,and the conditions under which, they are expected to contribute to the patenting process.The EPO has long recognized the inadequacies in simply assigning to third parties the roleof informant or amicus curiae and then leaving it to the Patent Office to use thematerial as it sees fit. Rather, the European Patent Convention (EPC) grants full partystatus to such participants, thus giving them some control on the way the material theyprovide is handled. While an extensive analysis is of course not possible here, thecomments and remarks on the benefits and drawbacks of the EPO opposition procedure willhopefully contribute to and spur further study and research on this topic.

Filing the Opposition

Within 9 months from the grant of a European patent, any person mayfile an opposition against a European patent with the objective of having it revoked orlimited by amendment.1 The notice of opposition must be inwriting and must state the extent to which the patent is opposed,2the grounds on which the opposition is based,3 and mustprovide relevant facts, evidence, and arguments relied on in support of the grounds foropposition.4

Admissibility of the Opposition

Before proceeding with the substantive examination, the opposition isfirst examined for admissibility.5 If an opposition isrejected as inadmissible, the respective proceedings are legally terminated without adecision as to the substance of the opposition being issued.6

As noted above, Rule 55 of the Implementing Regulations requires thenotice of opposition to state the basis for the opposition. Art. 100 EPC prescribes theonly grounds upon which an opposition may be based. Separated into three categories, thesegrounds are: 1) lack of patentability on the grounds of failure to comply with Articles 52to 57; 2) insufficient disclosure in accordance with Article 83; and 3) extension of theEuropean patent beyond the scope of what was contained in the application as originallyfiled.

Additionally, Rule 55(c) requires the notice of opposition to contain interalia "an indication of facts, evidence, and arguments presented in support of theaforementioned grounds." Thus, an opponent cannot confine herself to simply assertingone of the grounds for opposition mentioned under Art. 100, but must substantiate herallegation by providing arguments which demonstrate the logical link between the facts andevidence presented and the legal basis for the opposition.

It should be noted that the sufficiency of the notice of opposition isdistinguishable from the strength of the opponent’s case. Thus, an opposition may beadmissible even if a reading of the opponent’s case does not convince the reader thatit will succeed. Conversely, a deficient statement of the case may be rejected asinadmissible, even though it could have succeeded had it been properly formulated.

If the Formalities Officer considers that no further objection to theadmissibility of the opposition remains, she will invite the proprietor of the patent tocomment on the opposition. If the proprietor considers it necessary, she may also offeramendments intended to meet the opposition.7 The observationsand any amendments filed by the proprietor are then immediately communicated by theFormalities Officer to all opponents, who are then given an opportunity to comment on theproprietor’s submissions.8

Substantive Examination

Upon determination that the opposition is admissible, the next stage ofopposition is the substantive examination as to whether the grounds asserted in theopposition prejudice the maintenance of the European patent.9Generally, the Opposition Division will first endeavor to reach a decision based on thewritten submissions and other written evidence. However, if the Opposition Divisionconsiders it expedient, or if any party requests oral proceedings, oral proceedings willbe held before the Opposition Division.

Proceedings for substantive examination before the Opposition Divisionare quite flexible since there is no fixed schedule of pleadings and counter-pleadingsbetween the parties. Rather, parties are invited by the Opposition Division "as oftenas necessary" to file observations on communications from the other party or from theOpposition Division itself.10

During the oral proceedings, the opponent generally speaks first,followed by the proprietor.11 Each party is given twoopportunities to speak, the first to make an opening statement and the second to reply tothe other party. The Opposition Division may question the parties to clarify matters. Atthe oral proceedings, the parties are not allowed to introduce new facts or evidenceunless the Opposition Division concludes upon briefly reading the document through that itis so important that it must exercise discretion and admit it under Art. 114(2). In suchcircumstances, the proceedings may be briefly interrupted to enable the other parties tostudy the new document, which may then - subject to the other party’s consent - beconsidered at the proceedings. If this consent is not forthcoming, the proceedings may beadjourned.12

After substantive examination of the grounds for opposition, theOpposition Division may decide to either revoke the unamended patent, reject theopposition to the unamended patent, or maintain the patent as amended.13The decision by the Opposition Division is then conveyed to the parties in writing.14 Upon receipt of the written decision, either party may file anappeal in accordance with Article 108 EPC.

Because the filing of an opposition and its conduct before the EPO aredirected to a single European patent, the revocation of a European patent by the EPO iseffective and final in all Contracting States in which it has effect.15

A Statistical Overview16

Although the existence of the opposition procedure under the EPC can beattributed, in part, to tradition, third party participation under the EPC owes itsvitality to more fundamental principles. The present European system is premised on thebasic philosophy that, to the greatest extent possible, discussions on the validity of aEuropean patent should be concentrated at the beginning.17This notion, coupled with the truism that examiners cannot be aware of all relevantdocuments and facts pertinent to the patentability of an invention, lead the drafters ofthe EPC to the conclusion that third party participation is a necessary adjunct toproceedings before the EPO to ensure a higher probability of validity than would bepossible by reliance solely on examination.18

Thus, based on prior experience with oppositions at national patentoffices, the drafters generally expected that about 20% to 25% of the European patentsgranted would be opposed. Contrary to these forecasts, however, recent studies show thatdespite the increase in the number of patents being issued, oppositions have been filedagainst just 6% to 8% of granted patents. Moreover, a brief glance at the outcome ofvarious oppositions in recent years shows that about 35% of the patents opposed arerevoked, approximately 30% are maintained in an amended form, and about 35% of theoppositions are rejected.

At first blush, the number of oppositions filed may seem surprisinglylow when compared to the 25% posted by the German Patent Office in earlier years. Althoughthis result may be attributed to disfavor for or dissatisfaction with the oppositionprocedure, other factors may account for this low turnout. First, trivial andinsignificant applications are usually not filed at the EPO but usually remain with thenational offices; and second, the EPO boasts a superior search procedure compared to thoseof the national offices.

Attitudes and Criticisms Towards Opposition

Additionally, different attitudes regarding the use of the oppositionprocedure may affect its eventual use by a third party. On the one hand, companies basedin countries which have long been familiar with opposition procedures, e.g. Germany, viewopposition as an extension of examination in order to limit a competitor’s rightwhile involving only a reasonable amount of effort. Consequently, the procedure is viewednot as an act of aggression but rather as a method of defining a competitor’sterritory. In such cases, third parties consciously and systematically monitor theEuropean patents granted to their competitors. Furthermore, the success rate ofoppositions, which indicate that 35% of the patents are revoked and about 30% are amended,provides added incentive to pursue this alternative.

On the other hand, a different attitude is evident by companies basedin other countries where oppositions were not the norm prior to joining the EPC. Becausesuch parties view opposition as tantamount to legal action or an act of aggression againstthe patentee, their use of the opposition procedure is minimal.

Perhaps the most common criticism of the EPO opposition procedure isthe length of time it takes for an ultimate decision to be issued. By some estimates, theentire opposition procedure, including appeals, may take up to five years or more beforereaching a final decision. The delay is usually a result of the desire of the examiningbody to give each party the opportunity to present its comments in full on each pointraised and to take account of every relevant document, argument or item of evidence, evenif submitted late.

However, the obvious advantages of the EPO opposition procedure overnational revocation procedures favor an EPO opposition despite this long delay. Forexample, the unique possibility of using a single opposition procedure to revoke thepatent in all designated Member States in which it has effect significantly underscoresthe preference for using the EPO opposition procedure as opposed to commencing individualnational proceedings. Furthermore, an opposition before the EPO involves members who arepredominantly technically qualified compared with judges presiding over proceedings at thenational level who are essentially trained only in the law.

Such significant differences in the role of the opposition procedurewithin the European patent system make it difficult to draw direct conclusions regardingthe success of an amended U.S. reexamination procedure. However, some key points areworthy of comment.

Remembering that the promotion of technological progess is thetouchstone of all patent legislation, the incentive to invent must embrace post-inventionconditions favorable to the inventor, which, at the same time, do not hinder thecompetitive market for improvements for the patented technology. In other words, thepatent laws must strike a delicate balance between granting monopoly rights to inventorsand protecting the public from the anti-competitive effects of monopolies. Increased thirdparty participation in the reexamination process, as embodied in the EPO oppositionprocedure, seems to best strike this balance between inventor and public and/orcompetitors while alleviating the disadvantages of the current reexamination procedure.More importantly, the outcomes of oppositions at the EPO (35% of the opposed patents beingrevoked and 30% requiring amendment) further underscore the essential role oppositionsplay in defining and limiting the territory between patent holders and the public domain.

However, to avoid the pitfalls of increased delay for oppositiondecisions, firm time limits for receiving and considering evidence should be set, therebyensuring that such procedures would be a true alternative to the expense and time oflitigation. Finally, as demonstrated by the different reactions to the EPO oppositionprocedure, the various attitudes of inventors and patent holders towards such a procedurewill probably be the most important indicator for determining how often such a system willbe utilized.

-- M. Trinidad Arriola

1Art. 99 EPC; Art. 102 EPC.
2Rule 55(c) of the ImplementingRegulations to the European Patent Convention (hereinafter "EPC Regulations").
5Rule 56 of EPC Regulations.
6T 925/91.
7Rule 57(1) of EPC Regulations.
8Rule 57(3) of EPC Regulations.
9Art. 101(1) EPC.
10Art. 101(2) EPC.
11EPO Examination Guidelines1994.
13Art. 102 EPC.
14EPO Examination Guidelines1994.
15Art. 99(2) EPC. Consequently,even if an opposition is filed in respect of only some of the designated countries, it istreated as being filed in respect of all of them.
16Statistics taken from theEuropean Patent Office, Annual Reports from the various years.
17Van Empel, Granting of EuropeanPatents 215.
18Singer, The European PatentConvention 459 (1995).

Last updated 4/27/2012