The discretionary power conferred by Art. 114 EPC necessarily implies that the EPO department of first instance must have a certain degree of freedom in exercising its power. A board of appeal should only overrule the way in which a department of first instance has exercised its discretion when deciding on a particular case if it concludes that it has done so according to the wrong principles, or without taking into account the right principles, or in an unreasonable way, and has thus exceeded the proper limits of its discretion (T 640/91, OJ 1994, 918; G 7/93, OJ 1994, 775; see also chapter V.A.3.5.). This rule also applies with respect to opposition division decisions on the admission of late‑filed submissions (T 1209/05, T 1485/08, T 1652/08, T 1253/09, T 1852/11, T 2513/11, T 1568/12, T 1883/12, T 1271/13, T 572/14; see also chapter V.A.3.5.5). It is not the function of a board of appeal to review all the facts and circumstances 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 such discretion in the same way (T 75/11; see however T 544/12, where the opposition division did not give sufficient reasons for its decision).
This discretionary power has to be exercised reasonably after hearing the parties, including in oral proceedings if requested (T 281/00).