27) In order to reach that conclusion, the General Court first verified, in paragraphs 60 to 70 of the judgment under appeal, whether, as Carreras Sequeros and Others maintained, Directive 2003/88 could be relied on against the EU legislature. While the General Court noted that a directive is not, as such, binding on the EU institutions, in paragraph 61 of the judgment it identified three situations in which those institutions would nevertheless be required to take account of directives. In particular, it considered whether Directive 2003/88 could be relied on against the EU legislature in so far as the directive gives expression to a fundamental right, in this instance the right to annual leave guaranteed in Article 31(2) of the Charter.

28) On the basis of the explanations of the Praesidium of the Convention relating to the Charter of Fundamental Rights (OJ 2007 C 303, p. 17), the General Court found, in paragraphs 69 and 70 of the judgment under appeal, that, ‘in so far as Directive 2003/88 is a concrete expression of the principle laid down in Article 31(2) of the Charter …, the legislature, bound as it is to comply with that article which has the same force as the Treaties, could not disregard the content of that directive’, in consequence of which the new Article 6 of Annex X to the Staff Regulations should be disapplied if it ‘is shown to be incompatible with the right to annual leave, the nature and purpose of which follow from Article 31(2) of the Charter read in the light of Directive 2003/88’.

29) Second, in proceeding to verify, in paragraphs 72 to 96 of the judgment under appeal, whether the right to annual leave was adversely affected by the new Article 6 of Annex X to the Staff Regulations, the General Court took into consideration the content of the provisions of Directive 2003/88 and its objective. The General Court held, in paragraphs 88 and 89 of that judgment, that, by its nature, the entitlement to annual leave referred to in Article 31(2) of the Charter is intended, in principle, to promote the improvement of the living and working conditions of workers, and that the fact that the number of days of annual leave determined by the new Article 6 of Annex X to the Staff Regulations remains higher than the minimum required under Article 7 of Directive 2003/88 is not sufficient, as the Commission claims, to conclude that the new article does not infringe the right to annual leave. 

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78) The arguments put forward by the Commission and the Council in support of these grounds of appeal, relating to the General Court’s findings in paragraphs 61 to 97 of the judgment under appeal, are, in essence, in four parts.

First two parts, alleging, respectively, an error of law regarding the ability to rely on directives against EU institutions, and the incorrect definition of the scope of the right to paid annual leave provided for in Article 31(2) of the Charter read in the light of Directive 2003/88

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81) In its response to the Council’s cross-appeal, the Commission states that it is difficult to understand whether paragraph 61 of the judgment under appeal serves as a basis for the claims that Directive 2003/88 can be relied on against the EU legislature and Article 31(2) of the Charter should be read in the light of that directive. However, should the Court of Justice find that the General Court’s substantive reasoning is based on the conditions for reliance on directives vis-à-vis the EU institutions, as set out in paragraph 61 of the judgment under appeal, the Commission makes clear that it also contests that point, as does the Council.

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83) According to the Commission, only the substance of Article 7 of Directive 2003/88, as a minimum protection rule, and not all of that directive’s provisions can, in accordance with the case-law of the Court, be taken into consideration in the context of the incidental review of the legality of a provision of the Staff Regulations concerning entitlement to annual leave in the light of Article 31(2) of the Charter.

84) The Council adds that, in the present case, the General Court distorted the scope of Article 52(7) of the Charter by some sophistry culminating in a review of the legality of Regulation No 1023/2013 – which introduced the new Article 6 of Annex X to the Staff Regulations – in the light of the provisions of Directive 2003/88, incorporating the latter directive into primary law, in disregard of the hierarchy of norms.

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93) However, it is sufficient to note that the operative part of the judgment under appeal is based not on the considerations set out in paragraphs 69 to 83 of that judgment but on the grounds set out in paragraphs 84 to 113 thereof, on the basis of which the General Court established that there was an unjustified adverse effect on Carreras Sequeros and Others’ right to paid annual leave, based on the disregard for the nature and purpose of that right, as referred to in Article 31(2) of the Charter.

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95) The Commission and the Council claim that the General Court’s statement, in paragraph 88 of the judgment under appeal, that the entitlement to annual leave referred to in Article 31(2) of the Charter is intended to promote the improvement of the living and working conditions of workers is incorrect.

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97) Nor, the Commission adds, does the objective of improving the living and working conditions of the persons concerned follow from reading Article 31(2) of the Charter in the light of Directive 2003/88, as the General Court stated in paragraph 70 of the judgment under appeal. There is nothing to justify incorporating the provisions of Directive 2003/88, other than Article 7 of that directive, into the content of the right to annual leave that is guaranteed in Article 31(2) of the Charter.

98) The references to Articles 151 and 153 TFEU in paragraph 85 of the judgment under appeal, which admittedly cover the Union’s social policy objectives, change nothing in that regard. Those provisions are, it is claimed, irrelevant in the present case, which is concerned with assessing the compatibility with Article 31(2) of the Charter of a legislative act adopted on the basis of Article 336 TFEU.

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102) According to the Commission and the Council, the new Article 6 of Annex X to the Staff Regulations respects the essence of the right to paid annual leave, as guaranteed in Article 31(2) of the Charter, as the number of days of annual leave granted as of right by the new Article 6, that is, 24 days as from 1 January 2016, remains higher than the minimum of four weeks – 20 days – required under Article 7 of Directive 2003/88. They argue that such a reduction in the number of days’ annual leave cannot be regarded as being unlawful in itself, contrary to the General Court’s finding in paragraph 90 of the judgment under appeal.

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104) Carreras Sequeros and Others contend first of all that, in the context of the present appeals, the institutions concerned do not explain clearly how their arguments should lead to the judgment under appeal being set aside. Even if Article 31(2) of the Charter is not intended to promote the improvement of the living and working conditions of workers, the fact remains that it is undoubtedly intended to improve protection of the health and safety of workers, within the meaning of Article 153(1) TFEU.

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106) Carreras Sequeros and Others add that the judgment under appeal follows on from the case-law of the Court (judgment of 6 November 2018, Bauer and Willmeroth, C‑569/16 and C‑570/16, EU:C:2018:871, paragraphs 81 to 84) according to which workers have the right to paid annual leave, the duration of which must be progressively harmonised, including, therefore, for the purposes of improving living and working conditions. Article 31(2) of the Charter cannot be interpreted differently from the principle which it is intended to reflect.

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109) As is apparent from paragraphs 84 to 97 of the judgment under appeal, the General Court found that, by adopting the new Article 6 of Annex X to the Staff Regulations significantly reducing the number of days of annual leave for officials and other members of staff serving in third countries, the EU legislature had adversely affected the right to annual leave, as protected by Article 31(2) of the Charter, even though the number of days of annual leave determined by that new Article 6 remained in all events higher than the minimum four weeks’ annual leave provided for in Article 7(1) of Directive 2003/88.

110) In that regard, it should be recalled that, as is apparent from Article 51(1) of the Charter, the provisions of the Charter are addressed, inter alia, to the EU institutions which are, therefore, required to respect the rights enshrined in it. Moreover, since Article 31(2) of the Charter has, pursuant to the first subparagraph of Article 6(1) TEU, the same legal value as the provisions of the Treaties, the EU legislature is required to observe it in particular when it adopts a measure such as the Staff Regulations on the basis of Article 336 TFEU (judgment of 19 September 2013, Review Commission v Strack, C‑579/12 RX‑II, EU:C:2013:570, paragraphs 39 and 58).

111) Article 31(2) of the Charter enshrines, for every worker, the right to a period of paid annual leave, but does not specify the exact duration of that period (see, to that effect, judgments of 6 November 2018, Bauer and Willmeroth, C‑569/16 and C‑570/16, EU:C:2018:871, paragraph 85, and of 6 November 2018, Max-Planck-Gesellschaft zur Förderung der Wissenschaften, C‑684/16, EU:C:2018:874, paragraph 74). Therefore, as the Advocate General noted in point 64 of her Opinion, the fundamental right to paid annual leave affirmed by that provision of the Charter requires, at least as regards the duration of that leave, concrete normative expression.

112) According to the explanations relating to Article 31 of the Charter, which, in accordance with the third subparagraph of Article 6(1) TEU and Article 52(7) of the Charter, must be taken into consideration for the interpretation of the Charter, Article 31(2) of the Charter is based on Council Directive 93/104/EC of 23 November 1993 concerning certain aspects of the organisation of working time (OJ 1993 L 307, p. 18), which was replaced and codified by Directive 2003/88 (see, to that effect, judgments of 19 September 2013, Review Commission v Strack, C‑579/12 RX‑II, EU:C:2013:570, paragraphs 27, 28 and 39, and of 6 November 2018, Max-Planck-Gesellschaft zur Förderung der Wissenschaften, C‑684/16, EU:C:2018:874, paragraphs 52 and 53).

113) That being the case, the right to paid annual leave as an essential and mandatory principle of EU social law, laid down in Article 31(2) of the Charter, is also derived, according to those explanations, from various instruments either drawn up by the Members States at EU level, such as the Community Charter of the Fundamental Social Rights of Workers, or on which the Member States have cooperated or to which they have acceded, such as the European Social Charter, to which all Member States are parties, both instruments being mentioned in Article 151 TFEU (see, to that effect, in particular, judgments of 19 September 2013, ReviewCommission v Strack, C‑579/12 RX‑II, EU:C:2013:570, paragraphs 26 and 27, and of 6 November 2018, Max-Planck-Gesellschaft zur Förderung der Wissenschaften, C‑684/16, EU:C:2018:874, paragraphs 70 to 73).

114) More specifically, the explanations relating to Article 31(2) of the Charter state that that provision is based on Article 2 of the European Social Charter and point 8 of the Community Charter of the Fundamental Social Rights of Workers, both of which affirm the right of every worker to paid annual leave, Article 2 of the European Social Charter guaranteeing the provision of a minimum of four weeks of paid annual leave.

115) Thus, it follows from the explanations relating to Article 31(2) of the Charter that the reference to Directive 2003/88 refers not, as the General Court wrongly found in paragraphs 69 to 83 of the judgment under appeal, to that directive as a whole – which, moreover, has a broader objective than the rights laid down in Article 31(2) of the Charter – but to the provisions of that directive which reflect and clarify the fundamental right to an annual period of paid leave, affirmed by that provision of the Charter. That is true, according to the case-law of the Court, of Article 7(1) of Directive 2003/88, which lays down a right to paid annual leave of at least four weeks (see, to that effect, judgments of 4 October 2018, Dicu, C‑12/17, EU:C:2018:799, paragraphs 24 and 25, and of 13 December 2018, Hein, C‑385/17, EU:C:2018:1018, paragraphs 22 and 23). 

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117) A provision, such as Article 7(1) of Directive 2003/88, which specifies, in EU law, the minimum duration of the annual period of paid leave to which every worker is entitled, by aligning itself in that respect with the period laid down in Article 2 of the European Social Charter which also underpins the fundamental right to paid annual leave affirmed in Article 31(2) of the Charter, cannot, by its very nature, constitute an adverse effect on that fundamental right. Article 7(1) of that directive merely gives concrete expression to that fundamental right.

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124) Last, contrary to what is maintained by the Commission, it must be acknowledged, in the light of point 8 of the Community Charter of the Fundamental Social Rights of Workers, that, as the General Court held in paragraph 88 of the judgment under appeal, the entitlement to annual leave provided for in Article 31(2) of the Charter is intended, in principle, to promote the improvement of the living and working conditions of workers.

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126) It follows that, contrary to what the General Court held, a provision of EU law, such as the new Article 6 of Annex X to the Staff Regulations, the purpose of which is to specify the duration of the right to annual leave for which officials and other members of staff serving in third countries are to be eligible, by ensuring that, in all events, their entitlement exceeds the minimum requirements laid down in Article 7(1) of Directive 2003/88, cannot be regarded as being contrary to the nature and purpose of the fundamental right to paid annual leave set out in Article 31(2) of the Charter.

127) It follows from all of the foregoing that the General Court could not, without erring in law in its assessment, find that, by adopting the new Article 6 of Annex X to the Staff Regulations, the EU legislature had adversely affected the fundamental right to paid annual leave referred to in Article 31(2) of the Charter, when the duration set by that new Article 6 of the paid annual leave of officials and members of the contract staff of the European Union serving in third countries remains higher, in all events, than the minimum period of four weeks required under Article 7(1) of Directive 2003/88.

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133) In that regard it is sufficient, however, to note that, for the reasons set out in paragraphs 110 to 127 of the present judgment, that plea must be rejected as being unfounded, since the duration of paid annual leave set by the new Article 6 of Annex X to the Staff Regulations over and above the minimum requirements of Article 7(1) of Directive 2003/88 does not in fact disregard the nature and purpose of the fundamental right of Carreras Sequeros and Others to an annual period of paid leave that is laid down by Article 31(2) of the Charter.

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150) In that regard, without there being any need to rule, in the present case, on the link which Carreras Sequeros and Others claim to have established between the rights laid down, respectively, in Article 7 and Article 31(2) of the Charter, it should be noted that the new Article 6 of Annex X to the Staff Regulations, which Carreras Sequeros and Others claim is unlawful, is exclusively concerned with the number of days of annual leave to which officials and other members of staff serving in third countries are entitled.