37 While the assessments carried out in the decision to initiate the formal examination procedure are indeed preliminary in nature, that does not mean that the decision lacks legal effects.
38 It must be pointed out in that regard that, if national courts were able to hold that a measure does not constitute aid within the meaning of Article 107(1) TFEU and, therefore, not to suspend its implementation, even though the Commission had just stated in its decision to initiate the formal examination procedure that that measure was capable of presenting aid elements, the effectiveness of Article 108(3) TFEU would be frustrated.
39 On the one hand, if the preliminary assessment in the decision to initiate the formal examination procedure is that the measure at issue constitutes aid and that assessment is subsequently confirmed in the final decision of the Commission, the national courts would have failed to observe their obligation under Article 108(3) TFEU [...] to suspend the implementation of any aid proposal until the adoption of the Commission’s decision on the compatibility of that proposal with the internal market.
40 On the other hand, even if in its final decision the Commission were to conclude that there were no aid elements, the preventive aim of the State aid control system established by the TFEU [...] requires that, following the doubt raised in the decision to initiate the formal examination procedure as to the aid character of that measure and its compatibility with the internal market, its implementation should be deferred until that doubt is resolved by the Commission’s final decision.
41 It is also important to note that the application of the European Union rules on State aid is based on an obligation of sincere cooperation between the national courts, on the one hand, and the Commission and the Courts of the European Union, on the other, in the context of which each acts on the basis of the role assigned to it by the Treaty. In the context of that cooperation, national courts must take all the necessary measures, whether general or specific, to ensure fulfilment of the obligations under European Union law and refrain from those which may jeopardise the attainment of the objectives of the Treaty, as follows from Article 4(3) TEU. Therefore, national courts must, in particular, refrain from taking decisions which conflict with a decision of the Commission, even if it is provisional.
42 Consequently, where the Commission has initiated the formal examination procedure with regard to a measure which is being implemented, national courts are required to adopt all the necessary measures with a view to drawing the appropriate conclusions from an infringement of the obligation to suspend the implementation of that measure (C-284/12, paras 37-42, emphasis added).
43 To that end [ie to draw the appropriate conclusions from an infringement of the obligation to suspend the implementation of that measure] national courts may decide to suspend the implementation of the measure in question and order the recovery of payments already made. They may also decide to order provisional measures in order to safeguard both the interests of the parties concerned and the effectiveness of the Commission’s decision to initiate the formal examination procedure.
44 Where they entertain doubts as to whether the measure at issue constitutes State aid within the meaning of Article 107(1) TFEU or as to the validity or interpretation of the decision to initiate the formal examination procedure, national courts may seek clarification from the Commission and, in accordance with the second and third paragraphs of Article 267 TFEU, as interpreted by the Court, they may or must refer a question to the Court for a preliminary ruling (see, to that effect, as regards requests for preliminary rulings on the validity of State aid, Case C-222/04 Cassa di Risparmio di Firenze and Others  ECR I-289, paragraphs 72 to 74) (C-284/12, paras 43-44, emphasis added).
In my view, this could be easily achieved by simply applying Article 4(3) of the Treaty on European Union, since the need for sincere cooperation in this type of matters seems out of the question (an argument the CJEU has used differently in Lufthansa). Nonetheless, it is now clear that the CJEU is not willing to go very far in striking a more sustainable balance between the sphere of jurisdiction/competence of domestic courts and ensuring a manageable procedural system in State aid law. In my view, domestic courts should resort to the possibilities outlined in para 44 of the Lufthansa Judgment only in very extreme cases (if ever).