The basic consideration for a decision on R. 142(1)(c) EPC is whether the representative concerned was either in a fit mental state to do the work required of him at the material time or whether he lacked the capacity to make rational decisions and to take the necessary actions, see J xx/xx (=J 900/85, OJ 1985, 159), J 7/99, J 7/16. In J 5/99 the Legal Board stated that that meant carefully weighing up all reliable relevant information. Also indispensable was a reliable medical opinion taking account of all material facts (see also J 7/16).
In J xx/xx (=J 900/85, OJ 1985, 159) the Legal Board noted that, although there were differences in the national laws of contracting states as to the concept of "legal incapacity" and as to its consequences, there seemed to be a broad agreement that a person of full age was legally incapacitated when he was suffering from such a disturbance of his mind that he was unable to form the necessary voluntary intention to carry out legal transactions which would be binding upon him, e.g. to make valid contracts. Such a disturbance of his mind could be recognised by national law even if it was temporary only (e.g. a disturbance caused by physical injury or by the influence of alcohol or other drugs) or occurred from time to time, as was the case with some mental illnesses in which the patient had lucid intervals. Disturbance of the mind causing legal incapacity was always recognised by law if it was of long duration, a fortiori if it was permanent and irreversible. Since there was a unified European profession of representatives before the EPO, there should be a uniform standard of judging legal incapacity, in order to avoid differences in the application of R. 90(1)(c) EPC 1973 (R. 142(1)(c) EPC) depending on the nationality or domicile of the representative. The question of determining the legal incapacity of a representative for the purposes of R. 90(1)(c) EPC 1973 (R. 142(1)(c) EPC) was one for the EPO, applying its own standards, developed in the light of experience and taking into consideration principles applied in the national laws of the contracting states. See also J 5/99, J 7/99.
The legal incapacity had to be of a persistent nature (J ../86 = J 901/86, OJ 1987, 528). For the purposes of R. 90(1)(c) EPC 1973 (R. 142(1)(c) EPC), the EPO must establish whether and if so when the representative was legally incapacitated, and in the light of its findings specify the time limits which might have been interrupted (J ../87 = J 902/87, OJ 1988, 323).
In J 7/99 the Legal Board held that legal incapacity pursuant to R. 90(1)(c) EPC 1973 (R. 142(1)(c) EPC) meant a mental state in which the representative was so totally or nearly totally unable to take rational decisions that all his professional duties, and not just one isolated case, were affected by his mental state. In the case in hand, legal incapacity was not established. See also J 2/98, J 7/16.
In T 315/87 of 14 February 1989 date: 1989-02-14 the board accepted that the previous representative had been suffering from physical and mental disorders. Indeed, the medical documents submitted by the previous representative himself pointed to a psychosomatic condition.