1 This request for a preliminary ruling concerns the interpretation of Article 3(1) and Article 5(1) of Directive 2008/104/EC of the European Parliament and of the Council of 19 November 2008 on temporary agency work (OJ 2008 L 327, p. 9) and Article 2(2) and Article 15 of Directive 2006/54/EC of the European Parliament and of the Council of 5 July 2006 on the implementation of the principle of equal opportunities and equal treatment of men and women in matters of employment and occupation (OJ 2006 L 204, p. 23).
2 The request has been made in proceedings between LM and Omnitel Comunicaciones SL, Microsoft Ibérica SRL (‘Microsoft’), Fondo de Garantía Salarial (Fogasa), Indi Marketers SL and Leadmarket SL concerning the application for annulment of the decision to dismiss LM and for compensation for the damage resulting therefrom.
3 Recitals 12 and 23 of Directive 2008/104 state: ‘(12) This Directive establishes a protective framework for temporary agency workers which is non-discriminatory, transparent and proportionate, while respecting the diversity of labour markets and industrial relations. … (23) Since the objective of this Directive, namely to establish a harmonised Community-level framework for protection for temporary agency workers, cannot be sufficiently achieved by the Member States and can therefore, by reason of the scale or effects of the action, be better achieved at Community level by introducing minimum requirements applicable throughout the Community, the Community may adopt measures in accordance with the principle of subsidiarity as set out in Article 5 of the Treaty. In accordance with the principle of proportionality, as set out in that Article, this Directive does not go beyond what is necessary in order to achieve that objective.’
4 Article 1 of that directive, entitled ‘Scope’, provides, in paragraphs 1 and 2: ‘1. This Directive applies to workers with a contract of employment or employment relationship with a temporary-work agency who are assigned to user undertakings to work temporarily under their supervision and direction. 2. This Directive applies to public and private undertakings which are temporary-work agencies or user undertakings engaged in economic activities whether or not they are operating for gain.’
5 Under Article 2 of that directive, entitled ‘Aim’: ‘The purpose of this Directive is to ensure the protection of temporary agency workers and to improve the quality of temporary agency work by ensuring that the principle of equal treatment, as set out in Article 5, is applied to temporary agency workers, and by recognising temporary-work agencies as employers, while taking into account the need to establish a suitable framework for the use of temporary agency work with a view to contributing effectively to the creation of jobs and to the development of flexible forms of working.’
6 Article 3 of that directive, entitled ‘Definitions’, provides, in paragraph 1: ‘For the purposes of this Directive: (a) “worker” means any person who, in the Member State concerned, is protected as a worker under national employment law; (b) “temporary-work agency” means any natural or legal person who, in compliance with national law, concludes contracts of employment or employment relationships with temporary agency workers in order to assign them to user undertakings to work there temporarily under their supervision and direction; (c) “temporary agency worker” means a worker with a contract of employment or an employment relationship with a temporary-work agency with a view to being assigned to a user undertaking to work temporarily under its supervision and direction; (d) “user undertaking” means any natural or legal person for whom and under the supervision and direction of whom a temporary agency worker works temporarily; (e) “assignment” means the period during which the temporary agency worker is placed at the user undertaking to work temporarily under its supervision and direction; (f) “basic working and employment conditions” means working and employment conditions laid down by legislation, regulations, administrative provisions, collective agreements and/or other binding general provisions in force in the user undertaking relating to: (i) the duration of working time, overtime, breaks, rest periods, night work, holidays and public holidays; (ii) pay.’
7 Article 5 of Directive 2008/104, entitled ‘The principle of equal treatment’, provides, in paragraph 1: ‘The basic working and employment conditions of temporary agency workers shall be, for the duration of their assignment at a user undertaking, at least those that would apply if they had been recruited directly by that undertaking to occupy the same job. For the purposes of the application of the first subparagraph, the rules in force in the user undertaking on: (a) protection of pregnant women and nursing mothers and protection of children and young people; and (b) equal treatment for men and women and any action to combat any discrimination based on sex, race or ethnic origin, religion, beliefs, disabilities, age or sexual orientation; must be complied with as established by legislation, regulations, administrative provisions, collective agreements and/or any other general provisions.’
8 Article 9 of that directive, entitled ‘Minimum requirements’, states, in paragraph 2: ‘The implementation of this Directive shall under no circumstances constitute sufficient grounds for justifying a reduction in the general level of protection of workers in the fields covered by this Directive. This is without prejudice to the rights of Member States and/or management and labour to lay down, in the light of changing circumstances, different legislative, regulatory or contractual arrangements to those prevailing at the time of the adoption of this Directive, provided always that the minimum requirements laid down in this Directive are respected.’
9 Article 2 of Directive 2006/54, entitled ‘Definitions’, provides: ‘1. For the purposes of this Directive, the following definitions shall apply: (a) “direct discrimination”: where one person is treated less favourably on grounds of sex than another is, has been or would be treated in a comparable situation; … 2. For the purposes of this Directive, discrimination includes: … (c) any less favourable treatment of a woman related to pregnancy or maternity leave within the meaning of [Council Directive 92/85/EEC of 19 October 1992 on the introduction of measures to encourage improvements in the safety and health at work of pregnant workers and workers who have recently given birth or are breastfeeding (tenth individual Directive within the meaning of Article 16(1) of Directive 89/391/EEC) (OJ 1992 L 348, p. 1)].’
10 Article 14 of Directive 2006/54, entitled ‘Prohibition of discrimination’, provides, in paragraph 1: ‘There shall be no direct or indirect discrimination on grounds of sex in the public or private sectors, including public bodies, in relation to: … (c) employment and working conditions, including dismissals, as well as pay as provided for in Article [157 TFEU]; …’
11 Under Article 15 of that directive, entitled ‘Return from maternity leave’: ‘A woman on maternity leave shall be entitled, after the end of her period of maternity leave, to return to her job or to an equivalent post on terms and conditions which are no less favourable to her and to benefit from any improvement in working conditions to which she would have been entitled during her absence.’
12 Article 43 of Real Decreto Legislativo 2/2015, por el que se aprueba el texto refundido de la Ley del Estatuto de los Trabajadores (Royal Legislative Decree No 2/2015 approving the consolidated text of the Workers’ Statute) of 23 October 2015 (BOE No 255 of 24 October 2015) (‘the Workers’ Statute’), entitled ‘Assignment of workers’, provides: ‘1. The hiring of workers for the purpose of their temporary assignment to another undertaking may be carried out only by duly authorised temporary-work agencies, in accordance with the rules laid down by law. …’
13 Under Article 55(6) of the Workers’ Statute: ‘A dismissal declared invalid shall entail the immediate reinstatement of the worker and the payment of any unpaid salary.’
14 Ley 14/1994 por la que se regulan las empresas de trabajo temporal (Law No 14/1994 on temporary-work agencies) of 1 June 1994 (BOE No 131 of 2 June 1994, p. 17408), as amended by Ley 35/2010, de medidas urgentes para la reforma del mercado de trabajo (Law No 35/2010 on urgent measures to reform the labour market) of 17 September 2010 (BOE No 227 of 18 September 2010, p. 79278) (‘Law No 14/1994’), transposes Directive 2008/104 into Spanish law.
15 Article 1 of Law No 14/1994 provides: ‘A temporary-work agency is an undertaking whose activity consists of assigning to another user undertaking, on a temporary basis, workers whom it employs. The recruitment of workers for the purpose of their temporary assignment to another undertaking may be carried out only by duly authorised temporary-work agencies, subject to the conditions laid down by this Law.’
16 Article 2 of that Law, entitled ‘Administrative authorisation’, provides, in paragraph 1: ‘Natural or legal persons intending to engage in the activity referred to in the preceding article must obtain prior administrative authorisation by proving to the competent administrative authority that the following conditions are met: (a) they have an organisational structure enabling them to fulfil their obligations as an employer in the light of the corporate objects. …’
17 Article 12 of that Law, entitled ‘Obligations of the agency’, provides, in paragraph 1: ‘The temporary-work agency shall be responsible for complying with salary and social security obligations vis-à-vis workers recruited for the purpose of their assignment to a user undertaking. …’
18 Article 15 of Law No 14/1994, entitled ‘Direction and supervision of work’, provides, in paragraph 1: ‘Where workers perform duties within the user undertaking, in accordance with the provisions of this Law, the powers of direction and supervision of work shall be exercised by that undertaking for the duration of the provision of services within it.’
19 After completing an occupational traineeship at Microsoft which lasted from September 2010 to June 2011, LM entered into successive employment contracts with three other undertakings, namely Omnitel Comunicaciones, Indi Marketers and Leadmarket, between 24 August 2011 and 1 August 2017. Those three undertakings had concluded successive contracts for the provision of services with Microsoft, under which LM was responsible for performing the contractually agreed services. Under the contract of employment concluded on 1 August 2017 between Leadmarket and LM, LM was employed as a sales consultant for Microsoft’s Original Equipment Manufacturer (OEM) department and performed marketing services for Microsoft which were not provided by any of its employees.
20 While LM was pregnant, Microsoft, citing budgetary reasons, informed Leadmarket that the contract for the provision of services between those two undertakings would end on 30 September 2020 and would not be renewed.
21 As from 22 September 2020, LM was temporarily unable to work. Subsequently, having given birth on 8 December 2020, she took maternity leave which was immediately followed by parental leave and annual leave. On the date of her return to work - 29 April 2021 - LM received a letter from Leadmarket informing her that her employment contract had been terminated with effect from 27 April 2021. The employer cited objective reasons for her dismissal, based on a reduction in demand due to a number of planned projects being dropped.
22 LM brought an action before the Juzgado de lo Social no 39 de Madrid (Social Court No 39, Madrid, Spain) seeking a declaration that her dismissal was invalid, or in the alternative unfair, and that Leadmarket and Microsoft were jointly and severally liable for the attendant consequences.
23 By judgment of 30 November 2021, the Juzgado de lo Social no 39 de Madrid (Social Court No 39, Madrid) absolved Microsoft from liability, taking the view that Leadmarket had not assigned LM to that company. In reaching that view, it observed that Leadmarket - and not Microsoft - organised LM’s working week and hours, paid her salary, provided her with training, authorised her leave and managed her maternity leave. It then held that LM’s dismissal by Leadmarket was unlawful and declared it invalid. However, it refused to uphold the claim for damages in respect of maternity-related discrimination on the ground that the real reason for the dismissal was based exclusively on budgetary grounds, even though the dismissal had taken place during a period of annual leave following a period of maternity leave and parental leave to care for a minor. It nevertheless ordered Leadmarket to pay LM the salary she had not been paid together with compensation for leave not taken.
24 LM brought an appeal against that judgment before the Tribunal Superior de Justicia de Madrid (High Court of Justice, Madrid, Spain), the referring court, arguing that her situation as an employee of Leadmarket should be regarded as an ‘assignment’, agreed with Microsoft, with the result that Microsoft should be declared jointly and severally liable for the consequences of the dismissal, including LM’s reinstatement to her post.
25 The referring court enquires, first of all, about the applicability of Directive 2008/104 to the dispute pending before it. It is unsure whether that directive applies to an undertaking which, without being recognised under national law as a temporary-work agency, assigns a worker to another undertaking. It points out in that regard that, under Spanish law, a temporary-work agency must hold a prior administrative authorisation in order to engage in that activity, something which that directive does not, however, appear to require.
26 Next, if the view is taken that Directive 2008/104 applies to this dispute, the referring court asks whether, in the present case, LM was assigned to Microsoft. It recalls that Article 3(1) of Directive 2008/104 defines the concepts of ‘temporary-work agency’, ‘temporary agency worker’, ‘user undertaking’ and ‘assignment’ on the premiss that the worker hired by the temporary-work agency provides his or her services ‘under [the] supervision and direction’ of the user undertaking. It points out that, in the present case, it is apparent from all the factors characterising the work carried out by LM that responsibility for the supervision and direction of her activities lay with Microsoft, which had supplied her with the computer that she used to provide, from her home, remote assistance to customers of a number of products of Microsoft, with whose managers she was in regular contact and to whose headquarters she travelled once a week, having an access card for that purpose. It also makes clear that, every month, Leadmarket’s director received a report on the worker’s activities, approved her leave and set her hours, so that the question arose as to whether Leadmarket had to be regarded as having retained the supervision and direction of the worker’s occupational activities.
27 Lastly, the referring court is uncertain whether it would be possible for LM to return to the post she held before her dismissal following the declaration of invalidity of that dismissal. It states that the post she held and the duties she performed prior to her maternity leave no longer exist within Leadmarket and that LM’s reinstatement to the same post could only be effective if it were to occur within Microsoft. It makes clear that the obligation to reinstate workers who have been dismissed after returning to work at the end of periods of suspension of the contract on account of childbirth, adoption, placement with a view to adoption or fostering, referred to in Article 45 of the Workers’ Statute, applies to the user undertaking and the assigning undertaking alike. In the present case, the question arises as to whether, owing to the fact that LM was recruited directly not by Microsoft but by Leadmarket, her right to return to work at Microsoft is lost, since Leadmarket alone is responsible for her reinstatement, or whether, on the contrary, the application of Article 5(1) of Directive 2008/104 means that the reinstatement obligation and the consequences of the dismissal being invalid are also enforceable against the user undertaking, namely Microsoft.
28 In those circumstances, the Tribunal Superior de Justicia de Madrid (High Court of Justice, Madrid) decided to stay the proceedings and to refer the following questions to the Court of Justice for a preliminary ruling: ‘(1) Whether Directive 2008/104/EC is applicable to an undertaking which assigns a worker to another undertaking, even if the first undertaking is not recognised by domestic legislation as a temporary-work agency on account of the fact that it does not have the relevant administrative authorisation; (2) Where Directive 2008/104/EC is applicable to undertakings which, without being recognised under domestic law as temporary-work agencies, assign workers [to other undertakings], if, in a situation such as that described above, the worker must be regarded as a temporary agency worker within the meaning of Article 3(1)(c) of Directive 2008/104/EC, must [Leadmarket] be regarded as a temporary-work agency within the meaning of Article 3(1)(b) of that directive and must [Microsoft] be regarded as a user undertaking within the meaning of Article 3(1)(d) of the same directive; in particular, whether it may be understood that [Leadmarket] retained the supervision and direction of the work (thereby precluding the existence of an assignment of the worker), on account of the fact that the director of that undertaking received a monthly activity report from the worker and also signed off the worker’s leave, holiday and hours, even if the day-to-day provision of the worker’s services consisted in attending to Microsoft customers, resolving incidents by frequently contacting Microsoft managers, and working from her home with a computer made available to the worker by Microsoft and attending the Microsoft workplace once a week; (3) If it is the case that Directive 2008/104/EC is applicable and we find ourselves dealing with an assignment of the worker, whether, as a consequence of the application of Article 5(1) of Directive 2008/104/EC, the salary of the worker must be at least the same as she would be entitled to if she had been recruited by [Microsoft] directly; (4) Whether, in the circumstances of the case, the right of the worker, under Article 15 of [Directive 2006/54/EC], to return to her job or another equivalent position following maternity leave is applicable. And whether, even though the contract between [Microsoft] and Leadmarket had ended, since there is no equivalent position at Leadmarket, the worker’s return to work must take place at [Microsoft]. (5) Where Directive 2008/104/EC is applicable on account of the fact that we are dealing with an assignment, whether, as a consequence of the application of Article 5(1) of Directive 2008/104/EC, the Spanish legal provisions which establish the nullity of dismissal in the case of pregnant workers and nursing mothers must lead to the temporary-work agency and the user undertaking being declared jointly and severally liable for the consequences laid down by law for a dismissal that is null and void, specifically: reinstatement of the worker to her job, payment of the salary not received from dismissal to reinstatement, and the obligation to pay the appropriate compensation arising from the unlawfulness of the dismissal.’
29 By its first question, the referring court asks, in essence, whether Article 3(1)(b) of Directive 2008/104 must be interpreted as meaning that that directive applies to an undertaking which assigns a worker to another undertaking even though the first undertaking is not recognised by domestic legislation as a temporary-work agency because it does not have the relevant administrative authorisation.
30 According to settled case-law, in interpreting a provision of EU law, it is necessary to consider not only its wording but also the context in which it occurs and the objectives pursued by the rules of which it is part (judgment of 12 May 2022, Luso Temp, C‑426/20, EU:C:2022:373, paragraph 29 and the case-law cited).
31 Article 3(1)(b) of Directive 2008/104 defines ‘temporary-work agency’ as any natural or legal person who, in compliance with national law, concludes contracts of employment or employment relationships with temporary agency workers in order to assign them to user undertakings to work there temporarily under the supervision and direction of those undertakings.
32 First of all, it is apparent from the wording of that provision that it contains no details regarding the status of the temporary-work agency. It merely states that the temporary-work agency must be a natural or legal person.
33 However, that provision makes clear that only undertakings which conclude contracts of employment or employment relationships with temporary agency workers, in compliance with national law, with the intention of assigning those workers to a user undertaking, are covered by that concept (see, to that effect, judgment of 22 June 2023, ALB FILS Kliniken, C‑427/21, EU:C:2023:505, paragraph 44). It is apparent from the wording of that provision that the requirement of compliance with national law refers to the procedure for concluding contracts of employment or the manner of concluding employment relationships.
34 It should also be noted that Directive 2008/104 does not make the status of ‘temporary-work agency’ subject to the condition that an undertaking must assign a certain number or percentage of workers to another undertaking in order to be regarded as a temporary-work agency within the meaning of Article 3(1)(b) of that directive.
35 Nothing in the definition of ‘temporary-work agency’, as set out in Article 3(1)(b) of Directive 2008/104, requires that, for an undertaking to be regarded as a temporary-work agency within the meaning of that directive, it must have prior administrative authorisation to engage in that activity in the Member State in which it operates.
36 That interpretation of Article 3(1)(b) of Directive 2008/104 is supported by the context of that provision.
37 In that regard, it must be borne in mind that Directive 2008/104 was adopted to supplement the regulatory framework established by Council Directive 97/81/EC of 15 December 1997 concerning the Framework Agreement on part-time work concluded by UNICE, CEEP and the ETUC (OJ 1998 L 14, p. 9) and Council Directive 1999/70/EC of 28 June 1999 concerning the framework agreement on fixed-term work concluded by ETUC, UNICE and CEEP (OJ 1999 L 175, p. 43), on the basis of Article 137(1) and (2) EC, which empowered the institutions to adopt, by means of directives, minimum requirements for gradual implementation relating, inter alia, to working conditions (judgment of 14 October 2020, KG (Successive assignments in the context of temporary agency work), C‑681/18, EU:C:2020:823, paragraph 39).
38 To that end, as is apparent from Article 9(2) of Directive 2008/104, that directive provides only for the introduction of minimum requirements (see, to that effect, judgment of 14 October 2020, KG (Successive assignments in the context of temporary agency work), C‑681/18, EU:C:2020:823, paragraph 41).
39 It should be observed that Article 1(2) of Directive 2008/104, which, in referring to temporary-work agencies, merely states that that directive applies to ‘public and private undertakings which are temporary-work agencies or user undertakings engaged in economic activities whether or not they are operating for gain’, therefore leaves a broad discretion to the Member States.
40 That finding is, moreover, supported by the objectives pursued by Directive 2008/104, as set out in recitals 12 and 23 and Article 2 of that directive, which seek to establish a protective framework for workers that is non-discriminatory, transparent and proportionate, by ensuring that the principle of equal treatment is applied to those workers and by recognising temporary-work agencies as employers through the introduction of minimum requirements while allowing Member States to provide for penalties.
41 Interpreting the scope of Directive 2008/104 as covering only undertakings which, under their domestic law, hold a prior administrative authorisation to operate as a temporary-work agency (i) would mean that the protection of workers would vary between Member States, depending on whether or not national law requires such authorisation, and within the same Member State, depending on whether or not the undertaking in question holds such authorisation, and would risk undermining the objectives of that directive, which are to protect temporary agency workers, and (ii) would undermine the effectiveness of that directive by inordinately and unjustifiably restricting its scope.
42 Such a limitation would allow any undertaking that, without being in possession of such authorisation, assigns to other undertakings workers who have concluded a contract of employment with it to escape the application of Directive 2008/104 and, therefore, would impede workers from receiving the protection afforded by that directive, even though the employment relationship between those persons and the undertaking assigning them is not substantially different from the relationship they would have with an undertaking that had obtained prior administrative authorisation as required under national law.
43 In the light of the foregoing considerations, the answer to the first question is that Article 3(1)(b) of Directive 2008/104 must be interpreted as meaning that that directive applies to any natural or legal person who enters into a contract of employment or an employment relationship with a worker in order to assign him or her to a user undertaking to work there temporarily under that undertaking’s supervision and direction, and who assigns that worker to that undertaking, even though that person is not recognised by domestic legislation as a temporary-work agency because the person does not have the relevant administrative authorisation.
44 By its second question, the referring court asks, in essence, whether Article 3(1)(b) to (d) of Directive 2008/104 must be interpreted as meaning that the concept of ‘temporary agency work’ for the purposes of that provision covers (i) an undertaking not recognised under national law as a temporary-work agency, but which assigns (ii) one of its employees, in respect of whom it receives a monthly activity report and retains responsibility for managing working hours and leave, to (iii) another undertaking, in order to have that employee work on a daily basis under the supervision and direction of that other undertaking.
45 Microsoft argues that this question should be declared inadmissible because it seeks to have the Court assess the facts submitted by the referring court concerning the possible assignment of LM.
46 In that regard, it should be borne in mind that, when the Court is requested to give a preliminary ruling, its task is to provide the national court with guidance on the scope of the rules of EU law so as to enable that court to apply the rules correctly to the facts in the case before it and it is not for the Court of Justice to apply those rules itself, a fortiori since it does not necessarily have available to it all the information that is essential for that purpose (judgment of 18 June 2015, Martin Meat, C‑586/13, EU:C:2015:405, paragraph 31).
47 It is true that the Court has no jurisdiction to assess the facts in the main proceedings or to apply the rules of EU law which it has interpreted to national measures or situations, since those questions are matters for the exclusive jurisdiction of the national court (judgment of 9 March 2021, Radiotelevizija Slovenija (Period of stand-by time in a remote location), C‑344/19, EU:C:2021:182, paragraph 23).
48 However, it should be observed that, by its second question, the referring court enquires about the scope of the concepts of ‘temporary-work agency’, ‘temporary agency worker’ and ‘user undertaking’‘under [the] supervision and direction’ of which the temporary agency worker performs his or her duties, within the meaning of Article 3(1) of Directive 2008/104.
49 Therefore, since that question concerns the interpretation of Directive 2008/104, it is admissible.
50 It should be noted at the outset that it is for the national court to determine whether a worker performs his or her duties under the supervision and direction of a user undertaking or of the employer which hired him or her and concluded a contract for the provision of services with that undertaking. However, the Court, when giving a preliminary ruling, may, where appropriate, provide clarification designed to give the referring court guidance in its interpretation (see, to that effect, judgment of 22 November 2017, Cussens and Others, C‑251/16, EU:C:2017:881, paragraph 59).
51 As regards, in the first place, the concept of ‘temporary-work agency’, it is apparent from Article 1(1) and (2) of Directive 2008/104, concerning the scope of that directive, and from Article 3(1)(b) to (e) thereof, that a temporary-work agency is an undertaking which concludes contracts of employment or employment relationships with workers in order to assign them to user undertakings to work there temporarily ‘under [the] supervision and direction’ of those undertakings.
52 As is clear from paragraph 34 above, Directive 2008/104 does not make the status of ‘temporary-work agency’ subject to the condition that an undertaking must assign a certain number or percentage of workers to another undertaking. Nonetheless, it is not sufficient, for the purposes of classifying an undertaking as a temporary-work agency, for that undertaking to assign one or other of its workers, or occasionally a proportion of its workers, to another undertaking. Such situations in effect amount to the provision of services by one undertaking to another and not to the provision of temporary agency work.
53 Therefore, if the referring court were to find that the worker’s employer is an undertaking whose activity - whether or not its main activity - is to conclude contracts of employment or employment relationships with workers in order to assign them temporarily to user undertakings to work there under their supervision and direction, it would have to take the view that Directive 2008/104 applies to the main proceedings, which would enable it to determine whether the worker at issue in those proceedings may be regarded as a temporary agency worker performing her duties under the supervision and direction of a user undertaking within the meaning of Directive 2008/104.
54 As regards, in the second place, the concept of ‘temporary agency worker’, defined in Article 3(1)(c) of Directive 2008/104, it must be borne in mind that, according to settled case-law, the concept of ‘worker’ may not be interpreted differently according to each national law, but has its own meaning in EU law (see, to that effect, judgment of 20 September 2007, Kiiski, C‑116/06, EU:C:2007:536, paragraph 25 and the case-law cited).
55 The concept of ‘worker’ is defined in accordance with objective criteria which distinguish the employment relationship by reference to the rights and duties of the persons concerned. The essential feature of an employment relationship is that, for a certain period of time, a person performs services for and under the direction of another person, in return for which he or she receives remuneration (see, inter alia, judgment of 11 April 2019, Bosworth and Hurley, C‑603/17, EU:C:2019:310, paragraph 25 and the case-law cited).
56 However, the assignment of temporary agency workers is a complex situation which is specific to labour law, involving a twofold employment relationship between, on the one hand, the temporary-work agency and the temporary agency worker and, on the other, the temporary agency worker and the user undertaking, as well as a relationship of assignment between the temporary-work agency and the user undertaking (judgment of 11 April 2013, Della Rocca, C‑290/12, EU:C:2013:235, paragraph 40).
57 The particularity of that employment relationship lies in the fact that, when a temporary agency worker is assigned, the temporary-work agency retains an employment relationship with that worker, but transfers the responsibility for supervision and direction which generally lies with all employers to the user undertaking, thereby establishing a new relationship of subordination between the temporary agency worker and the user undertaking, whereby that worker provides a service contractually owed by the temporary-work agency to that undertaking and is placed, for that purpose, under the latter’s supervision and direction.
58 It follows that the question whether such a relationship of subordination exists and the degree of the temporary agency worker’s subordination to the user undertaking, in the performance of his or her duties, must be assessed in each particular case in the light of all the factors and circumstances characterising the relationship between the parties, an assessment which it will be for the referring court to carry out (see, to that effect, judgment of 20 November 2018, Sindicatul Familia Constanţa and Others, C‑147/17, EU:C:2018:926, paragraph 42 and the case-law cited).
59 In that regard, the fact that the temporary-work agency receives a monthly activity report from the worker assigned to the user undertaking is a factor which may, where appropriate, be taken into consideration, depending on the specific purpose pursued by that report in the relationship between the temporary-work agency and the worker. As for the fact that the temporary-work agency approves the temporary agency worker’s leave and sets his or her hours, it should be observed that it is not, a priori, unusual for the temporary-work agency, which is still that worker’s employer, formally to carry out those tasks, without that calling into question the genuineness of the supervision and direction of the worker for which the user undertaking has assumed responsibility in the context of his or her assignment. Nonetheless, it will be for the national court to determine, in the light of all the circumstances of the present case, whether other circumstances might suggest that it was the temporary-work agency which retained responsibility for the supervision and direction of its assigned worker.
60 As regards, in the third place, the concept of ‘user undertaking’, Article 3(1)(d) of Directive 2008/104 provides that that undertaking has a power of direction and supervision over the temporary agency worker. As such, not only may it require the temporary agency worker to comply with internal rules and working methods, but it may also monitor and supervise the way in which he or she performs his or her duties.
61 In that connection, in order to establish that a user undertaking exercises a power of direction and supervision over temporary agency workers, it is not sufficient for that undertaking to verify the work carried out or merely to give general instructions to those workers (see, to that effect, judgment of 18 June 2015, Martin Meat, C‑586/13, EU:C:2015:405, paragraph 40).
62 Consequently, the answer to the second question is that Article 3(1)(b) to (d) of Directive 2008/104 must be interpreted as meaning that the concept of ‘temporary agency work’ for the purposes of that provision covers the situation in which a worker is assigned to a user undertaking by an undertaking whose activity is to conclude contracts of employment or employment relationships with workers with a view to assigning them to a user undertaking for a given period of time, provided that that worker is under the supervision and direction of the user undertaking and provided that that undertaking, first, imposes on the worker the services to be performed, the manner of their performance and the requirement to comply with its instructions and internal rules, and, secondly, monitors and supervises the way in which the worker performs his or her duties.
63 By its third question, the referring court asks, in essence, whether Article 5(1) of Directive 2008/104 must be interpreted as meaning that a temporary agency worker assigned to a user undertaking must, for the duration of his or her assignment at that undertaking, receive a salary that is at least equal to that which he or she would have received if he or she had been recruited directly by that undertaking.
64 Under the first subparagraph of Article 5(1) of Directive 2008/104, the basic working and employment conditions of temporary agency workers must be, for the duration of their assignment at a user undertaking, at least those that would apply if they had been recruited directly by that undertaking to occupy the same job.
65 Article 3(1)(f) of that directive defines ‘basic working and employment conditions’ as those laid down by legislation, regulations, administrative provisions, collective agreements and/or other binding general provisions in force in the user undertaking relating, inter alia, to pay.
66 Consequently, the answer to the third question is that Article 5(1) of Directive 2008/104 must be interpreted as meaning that a temporary agency worker assigned to a user undertaking, within the meaning of that directive, must, for the duration of his or her assignment at that undertaking, receive a salary that is at least equal to that which he or she would have received if he or she had been recruited directly by that undertaking.
67 By its fourth question, the referring court asks, in essence, whether Article 15 of Directive 2006/54 must be interpreted as meaning that a pregnant worker or a worker who is breastfeeding, whose dismissal has been declared invalid by a national court, is entitled at the end of her maternity leave to return to her job or to an equivalent post at her employer or, where the contract for the provision of services between the user undertaking and the employer has ended and her employer has no equivalent post, at the user undertaking.
68 By its fifth question, the referring court asks, in essence, whether Article 5(1) of Directive 2008/104 must be interpreted as precluding legislation of a Member State under which, in that situation, the user undertaking and the temporary-work agency become jointly and severally liable for the consequences of the dismissal being invalid and are, in particular, required to reinstate that worker.
69 Since the order for reference serves as the basis for the procedure laid down in Article 267 TFEU, the national court is required, in that order for reference, to expand on its definition of the factual and legislative context of the dispute in the main proceedings and give the necessary explanation of the reasons for the choice of the provisions of EU law which it seeks to have interpreted and of the link it establishes between those provisions and the national law applicable to the proceedings pending before it (order of 9 January 2024, Bravchev, C‑338/23, EU:C:2024:4, paragraph 19 and the case-law cited).
70 In that regard, it should also be noted that the information contained in the order for reference must enable, first, the Court to provide useful answers to the questions referred by the national court and, secondly, the governments of the Member States and other interested parties to exercise the right conferred on them by Article 23 of the Statute of the Court of Justice of the European Union to submit observations. It is for the Court to ensure that that right is safeguarded, having regard to the fact that, under that provision, only the orders for reference are notified to the persons concerned (order of 9 January 2024, Bravchev, C‑338/23, EU:C:2024:4, paragraph 20 and the case-law cited).
71 The cumulative requirements concerning the content of an order for reference are set out explicitly in Article 94 of the Rules of Procedure of the Court of Justice and are recalled, in particular, in paragraph 15 of the Recommendations of the Court of Justice of the European Union to national courts and tribunals in relation to the initiation of preliminary ruling proceedings (OJ 2019 C 380, p. 1).
72 Article 94(c) of those rules thus provides that the request for a preliminary ruling is to contain a statement of the reasons which prompted the referring court or tribunal to inquire about the interpretation or validity of certain provisions of EU law.
73 In that regard, it should be borne in mind that, according to settled case‑law, questions on the interpretation of EU law referred by a national court in the legislative and factual context which that court is responsible for defining, and the accuracy of which is not a matter for the Court to determine, enjoy a presumption of relevance. The Court may refuse to rule on a request for a preliminary ruling submitted by a national court only where it is quite obvious that the interpretation of EU law that is sought bears no relation to the actual facts of the main action or its purpose, where the problem is hypothetical, or where the Court does not have before it the factual or legal material necessary to give a useful answer to the questions submitted to it (judgment of 7 July 2022, Coca-Cola European Partners Deutschland, C‑257/21 and C‑258/21, EU:C:2022:529, paragraph 35 and the case-law cited).
74 In the present case, it should be noted, in the first place, that it has not been established that the employer of the worker at issue in the main proceedings is a temporary-work agency, that is to say, an undertaking whose activity is to assign workers to user undertakings and to conclude contracts of employment or employment relationships with workers in order to assign them temporarily to user undertakings.
75 In the second place, it is in no way apparent from the file submitted to the Court that an employment relationship still existed between Microsoft and LM when the latter was dismissed. Indeed, with effect from the beginning of LM’s maternity leave, Leadmarket no longer assigned LM to Microsoft and, according to the referring court, the contractual relationship between Microsoft and Leadmarket came to an end on 30 September 2020, several months before Leadmarket dismissed LM, rendering the two questions referred hypothetical.
76 Furthermore, there is nothing in the order for reference that makes it possible to determine the nature of the employment contract between LM and Leadmarket. In addition, the referring court does not provide any explanation for its view that, against that background, the interpretation of Article 15 of Directive 2006/54 and Article 5(1) of Directive 2008/104 would be applicable to LM’s situation, given that, in particular, the contract for the provision of services concluded between Microsoft and Leadmarket ended on 30 September 2020, several months before LM’s dismissal.
77 In the light of the foregoing, the Court finds that the fourth and fifth questions referred for a preliminary ruling are inadmissible.
78 Since these proceedings are, for the parties to the main proceedings, a step in the action pending before the referring court, the decision on costs is a matter for that court. Costs incurred in submitting observations to the Court, other than the costs of those parties, are not recoverable.