The criteria for accepting or refusing requests for amendment under R. 137(3) EPC (former R. 86(3) EPC 1973), or correction under R. 139 EPC (former R. 88 EPC 1973), have not been changed by new R. 71 EPC (former R. 51 EPC 1973), which entered into force on 1 April 2012 (OJ 2010, 637).

Decision G 7/93 (OJ 1994, 775) dealt with the criteria for assessing the admissibility of late-filed amendments in examination. In particular, applying the principles of G 7/93 to amendments filed in response to the communication under R. 71(3) EPC means that this communication does not constitute an opportunity for the applicant to call into question the outcome of the earlier procedure (T 375/90). The Enlarged Board noted that the question whether an approval submitted under R. 51(4) EPC 1973 becomes binding once a communication in accordance with R. 51(6) EPC 1973 has been issued depended rather upon the proper interpretation of Art. 123(1) EPC in conjunction with R. 86(3) EPC 1973. The Enlarged Board came to the conclusion that the approval of a notified text submitted by an applicant pursuant to R. 71(3) EPC (former R. 51(4) EPC 1973) does not become binding. It stated that, in general terms, the way in which the examining division should exercise its discretion to allow an amendment of an application must depend upon the circumstances of each individual case, and must also depend upon the stage of the pre-grant procedure which the application has reached. It is clear from the wording of the provisions in R. 51(4) to (6) EPC 1973 that the underlying object of the R. 51(6) EPC 1973 communication is to conclude the granting procedure on the basis of the previously notified and approved text of the application. Thus although the examining division still has a discretion to allow amendments at this stage of the pre-grant procedure, such discretion must be exercised with the above underlying object in mind. In particular it held that admission of amendments at a late stage of the proceedings is to be the exception and not the rule.

In T 1064/04 the board stated that the principles in G 7/93 could be considered generally applicable to new requests put forward at a late stage of the proceedings, where the applicant had already had at least one opportunity to amend the application and the examining division has already completed substantive examination of the application. The board found that the examining division had exercised its discretion in a reasonable way in accordance with the applicable principles. A late stage of the examination proceedings had been reached at the end of the oral proceedings, and any amendments thereafter fell to be considered under the principles derivable from decision G 7/93. T 1064/04 summarised the principles derived from decision G 7/93 (OJ 1994, 775) on admission of amendments at a late stage of proceedings (see also T 1540/11, T 1326/11). The principles that can be derived from decision of the Enlarged Board are:

(a) Until the issue of a decision to grant the patent, the examining division does have discretion under R. 86(3), second sentence, EPC 1973 (now R. 137(3) EPC)whether or not to allow the amendment of the application at a late stage, irrespective of whether the applicant has already agreed to a text (G 7/93, point 2.1 of the Reasons).

(b) The examining division is required to exercise its discretion considering all relevant factors, in particular the applicant's interest in obtaining a patent which is valid in all designated states, and the EPO's interest in bringing examination to a close, and must balance these against one another (G 7/93, points 2.2 and 2.3 of the Reasons).

(c) Allowing a request for amendment at a late stage of the examination proceedings, that is, against the background that the applicant has already had at least one opportunity to amend the application and that the examining division has already completed the substantive examination of the application, will be an exception and not the rule (G 7/93, point 2.3 of the Reasons).

(d) It is not the function of a board of appeal to review all the facts of the case as if it were in the place of the department of first instance, in order to decide whether or not it would have exercised the discretion in the same way as the department of first instance. Rather a board of appeal should only overrule the way in which the department of first instance exercised its discretion if it comes to the conclusion either that the department of first instance has not exercised its discretion in the right way as set out in (b) above or has exercised its discretion in an unreasonable way, and thus exceeded the proper limits of its discretion (G 7/93, point 2.6 of the Reasons).

In T 1399/10 the board held that if an examining division comes to the conclusion that a request is not prima facie allowable but introduces new deficiencies, it is justified for the division to refuse the request under R. 137(3) EPC.

In T 1326/11 the decision under appeal dealt solely with the refusal under R. 137(3) EPC (2010) by the examining division to admit into the proceedings the request received after issuance of the communication under R. 71(3) EPC. Thus, the question to be decided on this appeal was whether this refusal was an appropriate exercise of the discretion given to the examining division under R. 137(3) EPC. Guided by the principles to be found on G 7/93 as summarised in T 1064/04, the board was of the view that the complexity of the case only supported the decision of the examining division not to admit a request at a very late stage of proceedings, which had already involved two communications of the examining division and oral proceedings before it. Admitting the request at that late stage would have led to re-examination and consequently unduly lengthened the proceedings.

In T 246/08 the board held that a refusal of consent to amend made in advance of any amendment being submitted cannot be a reasonable exercise of discretion pursuant to R. 137(3) EPC (former R. 86(3) EPC 1973) and is ipso facto a substantial procedural violation.

A number of decisions set out below relate to earlier versions of former R. 51(4) EPC 1973 (now R. 71(3) EPC). Nevertheless, they may also be applicable to the new R. 71(3) EPC.

In T 375/90 the board noted the conditions defined by the boards of appeal limiting the extent of the discretion which may be exercised when applying R. 86(3) EPC 1973, where amendments were proposed by the applicant after issue of the R. 51(4) EPC 1973 communication:

(i) There is no discretion in the obligation to admit amendments which remove deficiencies constituting violations of the EPC 1973 (see T 171/85, OJ 1987, 160; T 609/88).

(ii) In all other cases the EPO's interest in a speedy completion of the proceedings must be balanced against the applicant's interest in the grant of a patent with amended claims (see T 166/86, OJ 1987, 372; T 182/88, OJ 1990, 287; T 76/89).

The board noted that the Guidelines stated that the communication under R. 51(4) EPC 1973 did not constitute an opportunity for the applicant to call into question the outcome of the earlier procedure and only minor amendments would be considered within the period under R. 51(4) EPC 1973. It followed from the foregoing considerations that the examining division (or the board acting within its competence), when applying the provisions of R. 86(3) EPC 1973, is not completely free to deny any examination of the respective amended documents. See also T 989/99.

In T 999/93 the decision to refuse the application under R. 51(5), first sentence, EPC 1973 for lack of any approved text of the application (Art. 113(2) EPC 1973), was incorrect since the fact that the appellant never withdrew the main and first and second auxiliary requests as well as the appellant's letter (disapproval of the text proposed for grant, but request for a decision on the main request) clearly showed that he indeed approved and proposed the text according to his higher‑ranking requests (see also R. 51(5), second sentence, EPC 1973). The decision would instead have required reasoning as to the substance of the main, first auxiliary and second auxiliary requests.

In T 237/96 the board held that the broadening of the scope of claim 1 requested by the applicant after receipt of the examining division's communication under R. 51(4) EPC 1973 so as to encompass one originally disclosed embodiment was not consistent with his previous submission that said embodiment was not part of the invention, raised new issues as to clarity and inventive step and was not supported by any argumentation in favour of the allowability of the amended claim. The board found that the examining division, in refusing to consent to the amendment under R. 86(3) EPC 1973, did not exercise its discretion in a wrong or unreasonable manner. Had it given its consent to the amended version of the claim, it would have been necessary to restart examination from the beginning, which, given the prima facie lack of clarity of the claim, would have led to a considerable delay.

In T 1066/96 it was clear that further amendments could not be excluded wholesale in advance, but the discretion under R. 86(3) EPC 1973 had to be exercised on a case by case basis balancing the interests of the EPO and the applicant against one another (see G 7/93, OJ 1994, 775). Therefore, in exercising its discretion under R. 86(3) EPC 1973 in a negative way, an examining division could only refuse an application if, before issuing a decision, it had informed the applicant of the fact that the further amendments requested would not be admitted and of the reasons for not admitting said amendments, thereby taking due account of the applicant's reasons for such late filing of further amendments (see also T 2536/17). If the applicant maintained its request and its counterarguments were not considered convincing by the examining division, the application had to be refused under Art. 97(1) EPC 1973, since it contained no claims to which the applicant had agreed.

In T 121/06 the board held that issuing a communication under R. 51(4) EPC 1973 in which amendments were proposed, which the applicant could not reasonably be expected to accept without further discussion, constituted a substantial procedural violation.