In T 324/90 (OJ 1993, 33) the board held that in a large firm, where a considerable number of deadlines had to be monitored at any given time, it had normally to be expected that at least an effective system of staff substitution in the case of illness and for absences in general was in operation in order to ensure that official documents such as decisions by the EPO, which started periods within which procedural steps had to be carried out, were properly complied with.

In T 1401/05 of 20 September 2006 date: 2006-09-20 the board followed decisions T 324/90, J 41/92 and J 5/94 and deemed it necessary that reasonable provisions for absence due to the illness of a person who is in charge of monitoring time limits are made, unless in the particular circumstances of a case imposing such provisions would have to be considered as an undue burden. Only where any necessary provisions have been taken will it be possible to deem the monitoring system of time limits to be "normally satisfactory" (see T 324/90), and thus for considering illness to be an excuse for not meeting a deadline. Regarding the need for a back-up in the specific case, the board considered it of relevance that the number of time-limits to be complied with was small (the appellant filed only a few patent applications per year). Under these circumstances, the board accepted that it was not necessary for meeting the standard of due care to make specific provisions for the unforeseeable two-day illness of the sole employee in charge of monitoring of time limits; more specifically, no substitute for him had to be appointed.

In T 122/91 the board held that due care had not been exercised if the head of an office went off on a journey without informing his deputy of matters requiring immediate attention because a time limit was involved.

In J 41/92 (OJ 1995, 93) the Legal Board found that if a professional representative ran a one-person office, appropriate provisions needed to be made so that, in the case of an absence through illness, the observance of time limits could be ensured with the help of other persons. If there was no substitute or assistant at the representative's office, co-operation with colleagues or with a professional association could, for example, be sought for this purpose. See also T 387/11, in which the representative, who ran a one-person office, had taken precautions to ensure that another representative could cover for him if he were absent owing to illness, so that deadlines would normally be met. In taking such organisational measures, he had met the requisite standard of "all due care".

In T 677/02 the board decided that a large enterprise had not exercised all due care required by the circumstances if, when the representative actually responsible was on short time working, no deputy had been designated to cross-check the input of time limits into the system for monitoring time limits.