An introduction to clarity in EPO oppositions

In March 2015 the European Patent Office Enlarged Board of Appeal handed down a decision on the extent to which amendments made during opposition proceedings can be examined for clarity, following a referral from a lower board.

In the referral the referring board asked the question:

"Is the term ‘amendments’ as used in a previous Enlarged Board decision G 9/91 (see point 3.2.1) to be understood as encompassing a literal insertion of (a) elements of dependent claims as granted and/or (b) complete dependent claims as granted into an independent claim, so that opposition divisions and boards of appeal are required by Article 101(3) [of the European Patent Convention] always to examine the clarity of independent claims thus amended during the proceedings?"

The opposition which gave rise to this referral involved the combination of granted independent Claim 1 and granted dependent Claim 3, with it being claimed that Claim 3 contained a lack of clarity. Three further questions were referred and their answers were dependent on the answer to the first question. In the end, these further questions were all dealt with by the enlarged board’s answer to the first question.

The background to the case centred on Article 101(3) of the European Patent Convention, which allows the owner of an opposed European patent to amend claims:

"[i]f the Opposition Division is of the opinion that, taking into consideration the amendments made by the proprietor of the European patent during the opposition proceedings, the patent and the invention to which it relates (a) meet the requirements of this Convention, it shall decide to maintain the patent as amended, provided that the conditions laid down in the Implementing Regulations are fulfilled." 

However, following various cases before the boards of appeal, the extent to which the clarity of the amended claims could be examined during oppositions "in order to meet the requirements of this Convention" was inconsistent.

In G9/91 it had been confirmed that in case of amendments of claims or other parts of a patent in the course of opposition or appeal proceedings, such amendments must be fully examined as to their compatibility with the requirements of the European Patent Convention. However, this case did not specifically address the issue of clarity in opposition proceedings. The enlarged board had also previously decided that an opposition division or board of appeal is not obliged to consider all of the grounds for opposition going beyond the grounds covered by the statement of opposition, and should examine only such grounds for opposition which have been properly submitted and substantiated, but could nevertheless consider other, prima facie, grounds for opposition (see G10/91).  However, both G9/91 and G10/91 principally dealt with the extent to which an opposition division or board of appeal could – and should – decide on the maintenance of a European patent in respect of the extent to which the patent has been opposed. There had also been a number of cases heard by the boards of appeal which had followed the so-called 'conventional' approach when assessing the clarity of amendments – namely, the clarity of an amended claim could not be examined if the lack of clarity did not arise out of the amendment (see T301/87). However, there had been some divergence from this conventional approach and reference to an assessment as to whether an amendment made during opposition proceedings was minor, substantive or substantial (see T 409/10 and T 459/09). The conventional approach had called for an assessment of whether a lack of clarity would “arise out of” the amendments made – a phrase which had been interpreted broadly (see T472/88).

The enlarged board’s present decision was based in part on Article 84 of the European Patent Convention not being a ground for opposition – in this regard the legislature has rejected any suggestion or request that it should be a ground for opposition. According to the decision, about 70% of patents are amended during opposition proceedings and it was felt that examining clarity irrespective of the form of amendment made during opposition proceedings would go against the ethos of having a “streamlined opposition procedure”.

In its decision, the enlarged board stated that:

"[in] considering whether, for the purposes of Article 101(3) EPC, a patent as amended meets the requirements of the EPC, the claims of the patent may be examined for compliance with the requirements of Article 84 EPC only when, and then only to the extent that the amendment introduces non-compliance with Article 84 EPC."

In essence, an amendment is taken to be any amendment, including a combination of existing claims. The effect of this is that there is no requirement to consider whether an amendment is minor, substantive or substantial. Once an amendment has been made, it is necessary to assess whether it introduces a lack of clarity that was not present in the granted claims.

In ruling the enlarged board introduced the concept of different types of amendment – namely, Type A and Type B amendments. The Type A amendments were spilt into two further categories – namely, Type A(i) and Type A(ii). This characterisation of claim type appeared to be an attempt to make it easier to determine whether any amendments made during opposition proceedings should be examined for clarity.

Type B amendments were said to be the literal insertion of the subject matter of a dependent claim in to an independent claim. These amendments did not introduce non-compliance with Article 84 of the European Patent Convention and so the clarity of these amendments was not examined. 

Type A(i) amendments were said to be the insertion of one embodiment from multiple alternative embodiments from a single dependent claim, and thus had to be dealt with in the same manner as Type B amendments. 

The enlarged board acknowledged that for Type B and Type A(i) amendments, the resultant amended claim could be unclear due to an existing lack of clarity. However, the enlarged board appeared to say that national courts had mechanisms for dealing with this during national proceedings, so that any lack of clarity in the amended claims should be “left to smoulder”. 

Type A(ii) amendments were said to be the insertion of features which were disconnected from the amendment from other features of a dependent claim. There was no question that this type of amendment could be assessed for clarity – but only the amendment itself could be assessed.

The decision provides a clear indication that Type A(i) and Type B amendments should not be assessed for clarity. However, the extent to which Type A(ii) amendments can and will be assessed for clarity in future cases remains to be seen.

This is an Insight article, written by a selected partner as part of IAM's co-published content. Read more on Insight

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