That requirement must be appraised by reference to the circumstances of each case, in particular the content of the measure in question, the nature of the reasons given and the interest which the addressees of the measure, or other parties to whom it is of direct and individual concern, may have in obtaining explanations. It is not necessary for the reasoning to go into all the relevant facts and points of law, since the question whether the statement of reasons meets the requirements of Article 296 TFEU must be assessed with regard not only to its wording but also to its context and to all the legal rules governing the matter in question.

The statement of reasons required by Article 296 TFEU must be appropriate to the act at issue and must disclose in a clear and unequivocal fashion the reasoning followed by the institution which adopted the measure in question in such a way as to enable the persons concerned to ascertain the reasons for the measure and to enable the competent court to exercise its power of review.

An implementing act satisfies the duty to state reasons where it contains an express reference to the provisions of the regulation on which it is based, so that the criteria leading to its adoption can be understood.

It follows from the second paragraph of Article 1 of, and the Annex to Decision 2014/774 determining, pursuant to Regulation No 517/2014 on fluorinated greenhouse gases, reference values for the period 1 January 2015 to 31 December 2017 for each producer or importer who has reported placing on the market hydrofluorocarbons under Regulation No 842/2006, that the quantities of HFCs that producers or importers placed on the market during the reference period are calculated by adding together the quantities produced, the quantities imported and the difference in year-end stocks and subtracting the quantities exported.

Nothing within Regulation No 517/2014 explicitly provides that the difference in year-end stocks is a factor that should be taken into account in determining the reference value. Nor is it established that the difference in year-end stocks is a relevant criterion for determining the quantities of HFCs ‘placed on the market’ for the purposes of Article 2 point (10) of Regulation No 517/2014, in particular in the case of undertakings which neither produce nor use HFCs and simply import them in order to re-sell them or export them outside the Union.

It must be recognised that Annex V to Regulation No 517/2014, the object of which is to specify how the reference value is calculated, states that the calculation is based on the quantities of HFCs that the producers and importers have placed on the market in the Union during the reference or allocation period, ‘on the basis of available data’. The fact that Annex V to Regulation No 517/2014 provides for the reference value to be calculated ‘on the basis of available data’, and that Article 16(1) of that regulation states that the reference value is to be ‘based on the annual average of the quantities of HFCs the producer or importer reported to have placed on the market’, cannot be taken to mean that calculation of the reference value must necessarily be based only on the data reported under Article 6 of Regulation No 842/2006, concerning certain fluorinated greenhouse gases.

It would not be compliant with the objective of Regulation No 517/2014, which is the gradual reduction of the quantities of HFCs that can be ‘placed on the market’ in the Union, to use, when calculating the reference value, data not relevant to determining the quantities of HFCs placed on the market purely because they are ‘available data’. The fact that quantities in stock were reported does not necessarily mean that they were taken into account if they were not relevant to determining the quantities of HFCs placed on the market. Nor is it possible to accept the argument that non-availability of data relevant to calculating the reference value leads to the reference value not corresponding to the quantities of HFCs placed on the market. It is down to the Commission to approach the undertakings concerned in order to obtain the missing relevant data.

Thus, by taking into account the year-end balance of stocks for the purposes of calculating the reference value awarded to an undertaking which neither produces nor uses HFCs, Decision 2014/774 infringes Regulation No 517/2014.

(see paras 44, 51-53, 57, 59, 63, 69)