Art. 123(1) EPC provides that the applicant shall be given at least one opportunity to amend the application of his own volition. R. 137(3) EPC subjects any other amendments to the examining division's consent. As made clear by R. 100(1) EPC, this provision applies analogously on appeal against examining division decisions (T 1969/08). According to Art. 12(4) RPBA, the board has the power to hold inadmissible requests which were not admitted in the first instance proceedings.
It is the established jurisprudence of the boards of appeal that the power of the examining division to consent to amendments under R. 137(3) EPC is a discretionary power. According to G 7/93 (OJ 1994, 775) 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. A board of appeal should only overrule the way in which a department of first instance has exercised its discretion if it comes to the conclusion either that the department of first instance, in its decision, has not exercised its discretion in accordance with the right principles or that it has exercised its discretion in an unreasonable way. The exercise of a discretionary power has to strike a balance between, in particular, the applicant's interest in obtaining adequate protection for his invention and the EPO's interest in bringing the examination to a close in an effective and speedy way. Moreover, the exercise of a discretionary power has to be reasoned, otherwise it would be arbitrary (T 246/08). The board in T 1929/13 referred to further criteria, also set out in the Guidelines: (a) the amendments remedy a deficiency in response to the preceding communication, provided they do not give rise to new deficiencies; (b) the amendments improve the clarity of the description or claims in a clearly desirable manner; (c) need to avoid unnecessary delay and excessive and unjustified additional work for the EPO (Guidelines, H‑II, 2.3 – November 2015 version).