21In that regard, it should be recalled, first, that it is settled case-law that the time-limits laid down in Article 7 of Annex IX to the Staff Regulations are not mandatory but constitute rules of sound administration with the result that a failure to observe those time-limits may render the institution liable for any damage caused to those concerned, but cannot of itself affect the validity of a disciplinary sanction imposed after their expiry (see Van Eick v Commission, cited above, paragraphs 3 to 7, F. v Commission, cited above, paragraph 30, and M. v Council, cited above, paragraph 16).