The optional internal challenge procedures of the Bank must not, however, be used unfairly or in such a way as to detract from the principle of legal certainty which is an essential safeguard in relation to any administrative act liable to produce legal effects with regard to those to whom it is addressed.

The Staff Regulations of the European Investment Bank enable members of the Bank’s staff to request — before commencing legal proceedings and if they so wish — that an ad hoc procedure such as that brought before the Appeals Committee be opened, precisely so that the legality of an appraisal report can be verified, by an impartial body external to the department to which the member of staff belongs, and even, where appropriate, amended in its entirety, the Appeals Committee having power to substitute its assessment for that of the reporting officer in toto.

Staff of the European Investment Bank, like other staff and officials in the service of the Union, have the benefit, in disputes with their administration, of a two-tiered jurisdiction to review the legality of administrative acts adversely affecting them. The first tier is directly accessible to them before the Civil Service Tribunal, and a second tier is open to them in the form of an appeal, albeit limited to questions of law, before the General Court of the European Union. They may also have the benefit of a review of the appeal judgment, although the review procedure is initiated by and subject to the exclusive jurisdiction of the Court of Justice of the European Union, and thus is not at the parties’ disposal. Nevertheless, the possibility of the Court of Justice reviewing an appellate judgment issued by the General Court of the European Union constitutes a further safeguard in relation to the review of the legality of the administrative act in question, which ultimately benefits the parties.

On the other hand, as regards observance of the principle of legal certainty, neither the provisions of primary EU law governing the operation of the Bank, nor its Staff Regulations, contain provisions such as those appearing in Article 90 and Article 91 of the Staff Regulations of Officials of the EU, laying down mandatory time-limits for challenging before the EU judicature acts of the Bank having an adverse effect, such that once those time-limits have expired, the adverse act in question can in principle be regarded as final.

In this regard, in disputes between the Bank and a member of its staff concerning the appraisal of staff, where a period of over eight months has been taken to bring proceedings before the Civil Service Tribunal, calculated from the day on which the adverse act was communicated to the official concerned, this can be regarded as a reasonable period provided, first, that the member of staff in question opened any procedure before the Appeals Committee in connection with that act within a reasonable period and/or, secondly, that the person concerned also brought any request for conciliation within a reasonable time, this being judged with regard to all of the circumstances of the case.

(see paras 89-91)

Judgment of 16 September 2013 in De Nicola v EIB, T‑264/11 P, EU:T:2013:461, paragraph 52