1

This reference for a preliminary ruling relates to the interpretation of clause 4 of the Framework agreement on fixed-term work, concluded on 18 March 1999 (‘the Framework Agreement’), which is set out in the Annex to 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).

2

The request has been made in proceedings between Mr Carlos Álvarez Santirso and the Consejería de Educación, Cultura y Deporte del Principado de Asturias (Ministry of Education, Culture and Sports of the Autonomous Community of the Principality of Asturias (‘the Education Ministry’) concerning the latter’s decision not to admit the applicant to the procedure for registering for the first teaching evaluation plan.

3

Article 1 of Directive 1999/70 states that the purpose of the directive is ‘to put into effect the framework agreement on fixed-term contracts concluded … between the general cross-industry organisations (ETUC, UNICE and CEEP) annexed hereto’.

4

The first paragraph of Article 2 of that directive provides:

‘Member States shall bring into force the laws, regulations and administrative provisions necessary to comply with this Directive … [being required to] take any necessary measures to enable them at any time to be in a position to guarantee the results imposed by this Directive. ...’

5

According to clause 1 of the Framework Agreement, the objective of that agreement is, first, to improve the quality of fixed-term work by ensuring the application of the principle of non-discrimination and, secondly, to establish a framework to prevent abuse arising from the use of successive fixed-term employment contracts or relationships.

6

Paragraph 1 of Clause 2 of the Framework Agreement, entitled ‘Scope’, provides:

‘This agreement applies to fixed-term workers who have an employment contract or employment relationship as defined in law, collective agreements or practice in each Member State.’

7

Clause 3 of the Framework Agreement, entitled ‘Definitions’, provides:

8

Clause 4 of the framework agreement, headed ‘Principle of non-discrimination’, provides, at point 1:

‘In respect of employment conditions, fixed-term workers shall not be treated in a less favourable manner than comparable permanent workers solely because they have a fixed-term contract or relation unless different treatment is justified on objective grounds.’

9

The Ley del Principado de Asturias 3/1985 de Ordenación de la Función Pública de la Administración del Principado de Asturias (Law of the Principality of Asturias 3/1985 on the organisation of the civil service of the Government of the Principality of Asturias) of 26 December 1985 (BOE No 59 of 10 March 1986, p. 9083) provides in Article 6 that ‘interino’ (interim) civil servants are considered to be those who, having been legally appointed, temporarily occupy vacant posts within the workforce of the Government of the Principality of Asturias, until such time as those posts are filled by career civil servants, or who replace career civil servants in situations involving leave of absence or special service leave.

10

Under Article 106 of the Ley Orgánica 2/2006 de éducación (Basic Law 2/2006 on education) of 3 May 2006 (BOE No 106 of 4 May 2006, p. 17158), in order to improve the quality of education and teaching, the education authorities are to draw up plans for evaluating teachers, with the participation of teaching staff.

11

According to the Ley del Principado de Asturias 6/2009 de Evaluación de la Función Docente y sus Incentivos (Law of the Principality of Asturias 6/2009 on the evaluation of civil servants in the education sector and appurtenant incentives of 29 December 2009 (BOE No 53 of 2 March 2010, p. 20432), evaluation plans constitute a parameter of operation and measurement of the Asturian education system through analysis and evaluation of the tasks performed by the teaching staff. The law provides that the plans adopted are to cover, inter alia, absenteeism, workload of form teachers, participation in joint improvement or experimentation projects in extracurricular activities, greater involvement, taking on management positions and the contribution of teaching staff towards common objectives of the establishment as set out in the annual general programming.

12

Under Article 2 of Law 6/2009, the plans for evaluating teaching tasks are open to career civil servants belonging to teaching staff as set out in Basic Law 2/2006, who belong to the administrative staff and have five years’ length of service.

13

Article 3 of Law 6/2009 provides that persons who go beyond the requirements laid down in the evaluation plans will receive the teaching recognition incentive in the terms and for the amounts determined by the Regional Council when it approves the teaching evaluation plans.

14

The applicable rules thus provide that the granting of a financial incentive fixed at EUR 206.53 per month for career civil servants in sub-group A1 and EUR 132.18 per month for career civil servants in sub-group A2.

15

Mr Álvarez Santirso, who is employed as an interim civil servant, has for the past 16 years held a number of secondary school teaching posts, depending on post vacancies, in public educational establishments coming under the authority of the Autonomous Community of Asturias.

16

Further to a decision of 6 April 2015 of the Education Ministry opening the procedure for submitting applications to be included in the first teaching evaluation plan, Mr Álvarez Santirso submitted a duly completed application within the time limit.

17

By decision of 5 June 2015, the Education Ministry approved the final list of persons admitted at the end of the procedure for applying to be included in the first teaching evaluation plan. Mr Álvarez Santirso’s application was rejected due to his being an interim civil servant and because inclusion in the evaluation plan is reserved solely for career civil servants having at least five years’ length of service.

18

Mr Álvarez Santirso brought an administrative-law appeal against that decision before the Juzgado de lo Contencioso-Administrativo No 1 de Oviedo (Administrative Appeals Court No 1, Oviedo, Spain), arguing that there was unequal remuneration for career civil servants and interim civil servants arising solely from the temporary nature of the latters’ employment.

19

The representatives of the Principality of Asturias submit that the differential treatment at issue here is justified by objective grounds relating to differences in qualifications, skills and merit as demonstrated by success in the selection process, as career civil servants are required to meet more stringent requirements, thereby justifying their higher level of remuneration. In addition, granting interim civil servants the remuneration provided for under the career development arrangements would discriminate against career civil servants, given that their continued employment is dependent on the outcome of their evaluation.

20

The referring court expresses doubts as to the compatibility of the rules at issue with clause 4(1) of the Framework Agreement, inter alia in the light of the Court’s case-law, according to which the temporary nature of an employment relationship, in the absence of any justification by objective grounds, does not by itself justify differences in treatment with regard to employment conditions, be it a matter of additional remuneration in the form of a three-yearly supplement (judgment of 22 December 2010, Gavieiro Gavieiro and Iglesias Torres, C‑444/09 and C‑456/09, EU:C:2010:819), classification in a higher salary grade (judgment of 8 September 2011, Rosado Santana, C‑177/10, EU:C:2011:557) or claiming a six-yearly supplement for further training (order of 9 February 2012, Lorenzo Martínez, C‑556/11, not published, EU:C:2012:67).

21

In the present case, the referring court observes that the national rules at issue reserve the implementation of teaching evaluation plans for career civil servants, thereby excluding interim civil servants even if they have the required five years’ length of service and meet the criteria for qualifications, involvement in the establishment and contribution towards common objectives pursued by the establishment. In so far as those various criteria which are the subject of the evaluation can be met by both career civil servants and interim civil servants, the referring court takes the view that there are no objective grounds for reserving those evaluation plans exclusively for career civil servants.

22

The referring court states that a positive evaluation leads solely to the grant of a financial incentive and is completely unrelated to the promotion and career development system.

23

In those circumstances, the Juzgado de lo Contencioso-Administrativo No 1 de Oviedo (Administrative Appeals Court No 1, Oviedo, Spain) decided to stay the proceedings and to refer the following questions to the Court for a preliminary ruling:

‘Must Clause 4 of the [Framework Agreement] be interpreted as precluding … legislation such as [Law No 6/2009] which, under Article 2, makes eligibility for inclusion in the evaluation plan (with the resulting entitlement to the associated economic incentives) dependent on having the status of a career civil servant, thereby excluding interim civil servants?’

24

By its question, the referring court asks, in essence, whether clause 4(1) of the Framework Agreement must be interpreted as precluding national rules, such as those at issue in the main proceedings, which reserve participation in teaching evaluation plans and, in the case of a positive result, the ensuing financial incentives exclusively for teachers employed under permanent employment contracts as established career civil servants, thereby excluding persons employed as interim civil servants under fixed-term employment contracts.

25

Pursuant to Article 99 of the Rules of Procedure of the Court of Justice, where the answer to a question referred to the Court for a preliminary ruling may be clearly deduced from existing case-law or admits of no reasonable doubt, the Court may at any time, on a proposal from the Judge-Rapporteur and after hearing the Advocate General, give its decision by reasoned order.

26

That provision should be applied in the present case. The answer to the question referred may be clearly inferred from the Court’s case-law, in particular the judgments of 13 September 2007, Del Cerro Alonso, C‑307/05, EU:C:2007:509, 22 December 2010, Gavieiro Gavieiro and Iglesias Torres, C‑444/09 and C‑456/09, EU:C:2010:819; order of 18 March 2011, Montoya Medina, C‑273/10, not published, EU:C:2011:167; judgment of 8 September 2011, Rosado Santana, C‑177/10, EU:C:2011:557; order of 9 February 2012, Lorenzo Martínez, C‑556/11, not published, EU:C:2012:67; judgments of 18 October 2012, Valenza and Others, C‑302/11 to C‑305/11, EU:C:2012:646, 12 December 2013, Carratù, C‑361/12, EU:C:2013:830, and order of 7 March 2013, Bertazzi and Others, C‑393/11, not published, EU:C:2013:143.

27

First of all, it is clear from that case-law that Directive 1999/70 and the Framework Agreement are applicable to all workers providing remunerated services in the context of a fixed-term employment relationship linking them to their employer (judgments of 13 September 2007, Del Cerro Alonso, C‑307/05, EU:C:2007:509, paragraph 28; 22 December 2010, Gavieiro Gavieiro and Iglesias Torres, C‑444/09 and C‑456/09, EU:C:2010:819, paragraph 42; order of 18 March 2011, Montoya Medina, C‑273/10, not published, EU:C:2011:167, paragraph 26; judgment of 8 September 2011, Rosado Santana, C‑177/10, EU:C:2011:557, paragraph 40, and order of 9 February 2012, Lorenzo Martínez, C‑556/11, not published, EU:C:2012:67, paragraph 31).

28

The provisions laid down in the Framework Agreement therefore apply to fixed-term employment contracts and relationships concluded with the public authorities and other public-sector bodies (judgment of 22 December 2010, Gavieiro Gavieiro and Iglesias Torres, C‑444/09 and C‑456/09, EU:C:2010:819, paragraph 38 and the case-law cited; orders of 18 March 2011, Montoya Medina, C‑273/10, not published, EU:C:2011:167, paragraph 27, and 9 February 2012, Lorenzo Martínez, C‑556/11, not published, EU:C:2012:67, paragraph 32).

29

Since Mr Álvarez Santirso was employed as an interim civil servant under a fixed-term employment contract and performed the tasks of a secondary school teacher for over 16 years in various public educational establishments of the Autonomous Community of Asturias, he comes within the scope of Directive 1999/70 and the Framework Agreement.

30

Next, since under clause 4(1) of the Framework Agreement, fixed-term workers may not be treated in a less favourable manner than comparable permanent workers solely because they have a fixed-term contract or relation unless different treatment is justified on objective grounds, it must be determined whether participation in the teaching evaluation plan and the ensuing financial incentive in the event of a positive assessment come within the concept of ‘employment conditions’ within the meaning of that provision.

31

It should be recalled that, according to clause 1(a) of the Framework Agreement, one of its objectives is to improve the quality of fixed-term work by ensuring the application of the principle of non-discrimination. Similarly, the third paragraph in the preamble to the Framework Agreement states that it ‘illustrates the willingness of the Social Partners to establish a general framework for ensuring equal treatment for fixed-term workers by protecting them against discrimination’. Recital 14 in the preamble to Directive 1999/70 states with that in view that the aim of the Framework Agreement is, in particular, to improve the quality of fixed-term work by setting out minimum requirements in order to ensure the application of the principle of non-discrimination (see judgment of 22 December 2010, Gavieiro Gavieiro and Iglesias Torres, C‑444/09 and C‑456/09, EU:C:2010:819, paragraph 47; orders of 18 March 2011, Montoya Medina, C‑273/10, not published, EU:C:2011:167, paragraph 29, and 9 February 2012, Lorenzo Martínez, C‑556/11, not published, EU:C:2012:67, paragraph 34).

32

Clause 4 of the Framework Agreement aims to apply the principle of non-discrimination to fixed-term workers in order to prevent an employer using such an employment relationship to deny those workers rights which are recognised for permanent workers (judgments of 13 September 2007, Del Cerro Alonso, C‑307/05, EU:C:2007:509, paragraph 37; 22 December 2010, Gavieiro Gavieiro and Iglesias Torres, C‑444/09 and C‑456/09, EU:C:2010:819, paragraph 48; and orders of 18 March 2011, Montoya Medina, C‑273/10, not published, EU:C:2011:167, paragraph 30, and 9 February 2012, Lorenzo Martínez, C‑556/11, not published, EU:C:2012:67, paragraph 35).

33

In view of the objectives pursued by the Framework Agreement, clause 4 thereof must be interpreted as articulating a principle of EU social law which cannot be interpreted restrictively (see, to that effect, judgments of 13 September 2007, Del Cerro Alonso, C‑307/05, EU:C:2007:509, paragraph 38; 22 December 2010, Gavieiro Gavieiro and Iglesias Torres, C‑444/09 and C‑456/09, EU:C:2010:819, paragraph 49; orders of 18 March 2011, Montoya Medina, C‑273/10, not published, EU:C:2011:167, paragraph 31, and 9 February 2012, Lorenzo Martínez, C‑556/11, not published, EU:C:2012:67, paragraph 36).

34

Accordingly, the Court has held that the decisive criterion for determining whether a measure falls within the scope of ‘employment conditions’ within the meaning of clause 4(1) of the Framework Agreement is, precisely, the criterion of employment, that is to say the employment relationship between a worker and his employer (see, to that effect, judgment of 12 December 2013, Carratù, C‑361/12, EU:C:2013:830, paragraph 35).

35

Therefore, the concept of ‘employment conditions’ within the meaning of clause 4(1) of the Framework Agreement includes three-yearly length of service supplements (see, to that effect, judgments of 13 September 2007, Del Cerro Alonso, C‑307/05, EU:C:2007:509, paragraph 47; 22 December 2010, Gavieiro Gavieiro and Iglesias Torres, C‑444/09 and C‑456/09, EU:C:2010:819, paragraphs 50 to 58; and order of 18 March 2011, Montoya Medina, C‑273/10, not published, EU:C:2011:167, paragraphs 32 to 34), a six-yearly supplement for further training (see, to that effect, order of 9 February 2012, Lorenzo Martínez, C‑556/11, not published, EU:C:2012:67, paragraph 38) and rules concerning periods of service to be completed in order to be classified in a higher salary grade or calculation of the periods required to have performance assessed each year (see, to that effect, judgment of 8 September 2011, Rosado Santana, C‑177/10, EU:C:2011:557, paragraph 46 and the case-law cited).

36

In the present case, even if, as a rule, it is for the referring court to determine the nature and the objectives of the measures at issue, it is apparent from the evidence in the case file submitted by it to the Court that participation in the evaluation plan and the ensuing financial incentive in the event of a positive assessment must also be regarded as being ‘employment conditions’ within the meaning of clause 4(1) of the Framework Agreement.

37

On the one hand, the condition of five years’ length of service required to be included in the evaluation plan meets the decisive criterion referred to in paragraph [34] of the present order.

38

On the other hand, obtaining a positive assessment in the evaluation plan has no impact on the promotion and career development system, but results solely in a remuneration supplement. A component of remuneration in the form of a financial incentive must, as a condition of employment, be granted to a fixed-term worker on an equal footing with a permanent worker.

39

An interpretation of clause 4(1) of the Framework Agreement that excludes from the definition of ‘employment conditions’ the right to participate in the evaluation plan and the ensuing financial incentive in the event of a positive assessment has the effect of weakening the protection against discrimination granted to fixed-term workers, contrary to the objective pursued by that provision.

40

Lastly, it is settled case-law that, as regards employment conditions within the meaning of clause 4(1) of the Framework Agreement, fixed-term workers must not be treated less favourably than permanent workers in a comparable situation, in the absence of any objective justification (see, to that effect, judgments of 13 September 2007, Del Cerro Alonso, C‑307/05, EU:C:2007:509, paragraphs 42 and 47; 22 December 2010, Gavieiro Gavieiro and Iglesias Torres, C‑444/09 and C‑456/09, EU:C:2010:819, paragraph 53; order of 18 March 2011, Montoya Medina, C‑273/10, not published, EU:C:2011:167, paragraph 34; judgment of 8 September 2011, Rosado Santana, C‑177/10, EU:C:2011:557, paragraphs 56, 57 and 64, and order of 9 February 2012, Lorenzo Martínez, C‑556/11, not published, EU:C:2012:67, paragraph 40).

41

Since in the present case it is common ground that there is differential treatment of established career civil servants employed under a permanent employment contract as compared to interim civil servants employed under a fixed-term employment contract, it must first be examined whether the situation of the fixed-term workers and that of the permanent workers, at issue in the main proceedings, are comparable.

42

It must be remembered in that regard that the concept of ‘comparable permanent worker’ is defined in clause 3(2) of the Framework Agreement as ‘a worker with an employment contract or relationship of indefinite duration, in the same establishment, engaged in the same or similar work/occupation, due regard being given to qualifications/skills’ (orders of 18 March 2011, Montoya Medina, C‑273/10, not published, EU:C:2011:167, paragraph 36, and 9 February 2012, Lorenzo Martínez, C‑556/11, not published, EU:C:2012:67, paragraph 42).

43

In order to assess whether the persons concerned are engaged in the same or similar work for the purposes of the Framework Agreement, it must be determined, in accordance with clauses 3(2) and 4(1) of that agreement, whether, in the light of a number of factors, such as the nature of the work, qualifications requirements and working conditions, those persons can be regarded as being in a comparable situation (judgment of 18 October 2012, Valenza and Others, C‑302/11 to C‑305/11, EU:C:2012:646, paragraph 42 and the case-law cited; orders of 18 March 2011, Montoya Medina, C‑273/10, not published, EU:C:2011:167, paragraph 37, and 9 February 2012, Lorenzo Martínez, C‑556/11, not published, EU:C:2012:67, paragraph 43).

44

It is, in principle, for the referring court, and not the Court of Justice, to establish whether the established career civil servants and interim civil servants are in a comparable situation (see, by analogy, order of 18 March 2011, Montoya Medina, C‑273/10, not published, EU:C:2011:167, paragraph 39; judgments of 8 September 2011, Rosado Santana, C‑177/10, EU:C:2011:557, paragraph 67; 18 October 2012, Valenza and Others, C‑302/11 to C‑305/11, EU:C:2012:646, paragraph 43 and the case-law cited, and order of 9 February 2012, Lorenzo Martínez, C‑556/11, not published, EU:C:2012:67, paragraph 44).

45

In the main proceedings, however, there is nothing to indicate that teaching activities as carried out by teachers employed as established career civil servants and by teachers employed as interim civil servants require different academic qualifications or experience. On the contrary, the information in the order for reference indicates that both categories of teachers perform similar tasks and are subject to identical obligations, inter alia in the light of the criteria set out in the evaluation plans concerning qualifications, contribution towards the objectives of the establishment and involvement in that establishment’s activities.

46

Therefore, the only factor in the present case distinguishing a teacher employed as an interim civil servant from a teacher employed as an established career civil servant for the purposes of inclusion in the evaluation plan is the temporary nature of the employment relationship linking them to their employer.

47

In that scenario, it must be determined, second, whether there are objective grounds, within the meaning of clause 4(1) of the Framework Agreement, for that differential treatment.

48

It must be borne in mind in that regard that the concept of ‘objective grounds’ in clause 4(1) of the Framework Agreement must be understood as not permitting a difference in treatment between fixed-term workers and permanent workers to be justified on the basis that the difference is provided for by a general, abstract national norm, such as a law or collective agreement (judgments of 13 September 2007, Del Cerro Alonso, C‑307/05, EU:C:2007:509, paragraph 57; 22 December 2010, Gavieiro Gavieiro and Iglesias Torres, C‑444/09 and C‑456/09, EU:C:2010:819, paragraph 54; order of 18 March 2011, Montoya Medina, C‑273/10, not published, EU:C:2011:167, paragraph 40; judgment of 8 September 2011, Rosado Santana, C‑177/10, EU:C:2011:557, paragraph 72, and order of 9 February 2012, Lorenzo Martínez, C‑556/11, not published, EU:C:2012:67, paragraph 47).

49

Reliance on the mere fact of the temporary nature of the employment of staff of the public authorities does not meet those requirements and is therefore not capable of constituting an ‘objective ground’ within the meaning of clause 4(1) of the Framework Agreement (judgment of 22 December 2010, Gavieiro Gavieiro and Iglesias Torres, C‑444/09 and C‑456/09, EU:C:2010:819, paragraph 56; order of 18 March 2011, Montoya Medina, C‑273/10, not published, EU:C:2011:167, paragraph 42; judgment of 8 September 2011, Rosado Santana, C‑177/10, EU:C:2011:557, paragraph 74, and order of 9 February 2012, Lorenzo Martínez, C‑556/11, not published, EU:C:2012:67, paragraph 49).

50

A difference in treatment with regard to employment conditions as between fixed-term workers and permanent workers cannot be justified on the basis of a criterion which, in a general and abstract manner, refers precisely to the term of the employment. If the mere temporary nature of an employment relationship were held to be sufficient to justify such a difference, the objectives of Directive 1999/70 and the Framework Agreement would be negated. Instead of improving the quality of fixed-term work and promoting the equal treatment to which both Directive 1999/70 and the Framework Agreement aspire, reliance on such a criterion would amount to perpetuating a situation that is disadvantageous to fixed-term workers (judgment of 22 December 2010, Gavieiro Gavieiro and Iglesias Torres, C‑444/09 and C‑456/09, EU:C:2010:819, paragraph 57; orders of 18 March 2011, Montoya Medina, C‑273/10, not published, EU:C:2011:167, paragraph 43, and 9 February 2012, Lorenzo Martínez, C‑556/11, not published, EU:C:2012:67, paragraph 50).

51

That concept requires the unequal treatment at issue to be justified by the existence of precise and concrete factors, characterising the employment condition to which it relates, in the specific context in which it occurs and on the basis of objective and transparent criteria in order to ensure that that unequal treatment in fact responds to a genuine need, is appropriate for achieving the objective pursued and is necessary for that purpose. Those factors may result, in particular, from the specific nature of the tasks for the performance of which fixed-term contracts have been concluded and from the inherent characteristics of those tasks or, as the case may be, from pursuit of a legitimate social-policy objective of a Member State (judgments of 13 September 2007, Del Cerro Alonso, C‑307/05, EU:C:2007:509, paragraphs 53 and 58; 22 December 2010, Gavieiro Gavieiro and Iglesias Torres, C‑444/09 and C‑456/09, EU:C:2010:819, paragraph 55; order of 18 March 2011, Montoya Medina, C‑273/10, not published, EU:C:2011:167, paragraph 41; judgment of 8 September 2011, Rosado Santana, C‑177/10, EU:C:2011:557, paragraph 73, and order of 9 February 2012, Lorenzo Martínez, C‑556/11, not published, EU:C:2012:67, paragraph 48).

52

In the present case, the representatives of the Principality of Asturias have merely stated that entry-level requirements are lower for interim civil servants and referred to possible reverse discrimination against established career civil servants.

53

In view of the discretion enjoyed by Member States as regards the organisation of their own public administrations, they can, in principle, without acting contrary to Directive 1999/70 or the Framework Agreement, lay down period-of-service conditions for access to certain posts, restrict access to internal promotion solely to established career civil servants and require those civil servants to provide evidence of professional experience corresponding to the grade immediately below the grade concerned by the selection procedure (judgments of 8 September 2011, Rosado Santana, C‑177/10, EU:C:2011:557, paragraph 76; 18 October 2012, Valenza and Others, C‑302/11 to C‑305/11, EU:C:2012:646, paragraph 57, and order of 7 March 2013, Bertazzi and Others, C‑393/11, not published, EU:C:2013:143, paragraph 43).

54

However, that discretion notwithstanding, the criteria which the Member States lay down must be applied in a transparent manner and must be open to review in order to prevent any exclusion of fixed-term workers solely on the basis of the duration of the contracts or employment relationships which attest to their length of service and professional experience (judgments of 8 September 2011, Rosado Santana, C‑177/10, EU:C:2011:557, paragraph 77; 18 October 2012, Valenza and Others, C‑302/11 to C‑305/11, EU:C:2012:646, paragraph 59, and order of 7 March 2013, Bertazzi and Others, C‑393/11, not published, EU:C:2013:143, paragraph 44).

55

Where, in a selection procedure, such a difference in treatment flows from the need to take account of objective requirements relating to the post which that procedure is intended to fill and which are unrelated to the fixed-term nature of the interim civil servant’s employment relationship, it is capable of being justified for the purposes of clause 4(1) and/or (4) of the Framework Agreement (judgments of 8 September 2011, Rosado Santana, C‑177/10, EU:C:2011:557, paragraph 79; 18 October 2012, Valenza and Others, C‑302/11 to C‑305/11, EU:C:2012:646, paragraph 61, and order of 7 March 2013, Bertazzi and Others, C‑393/11, not published, EU:C:2013:143, paragraph 46).

56

On the other hand, a general and abstract condition to the effect that the five years’ length of service must have been entirely completed as a career civil servant, with no account being taken, in particular, of the specific nature of the tasks to be performed or their inherent characteristics, does not meet the requirements of the case-law on clause 4(1) of the framework agreement, as set out in paragraphs [48 to 51] of the present order.

57

Moreover, regarding the alleged objective of preventing reverse discrimination against established career civil servants recruited, it should be observed that, although that objective may constitute an ‘objective ground’ for the purposes of clause 4(1) and/or (4) of the Framework Agreement, it cannot, in any event, justify disproportionate national legislation such as that at issue in the main proceedings which completely and in all circumstances prohibits all periods of service completed by workers under fixed-term employment contracts being taken into account in order to determine the length of service of those workers upon their recruitment on a permanent basis and, thus, their level of remuneration (judgment of 18 October 2012, Valenza and Others, C‑302/11 to C‑305/11, EU:C:2012:646, paragraph 62, and order of 7 March 2013, Bertazzi and Others, C‑393/11, not published, EU:C:2013:143, paragraph 47).

58

A fortiori is this the case where, as in the main proceedings here, the national rules provide for inclusion in the teaching evaluation plan and a remuneration supplement in the event of a positive assessment only to teachers employed as established career civil servants having completed five years’ length of service, whereas teachers employed as interim civil servants fulfil exactly the same entrance criteria but are excluded from the benefits.

59

Lastly, it must be remembered that clause 4(1) of the Framework Agreement is unconditional and sufficiently precise for individuals to be able to rely on it before a national court as against the State (see, to that effect, judgment of 22 December 2010, Gavieiro Gavieiro and Iglesias Torres, C‑444/09 and C‑456/09, EU:C:2010:819, paragraphs 78 to 83; order of 18 March 2011, Montoya Medina, C‑273/10, not published, EU:C:2011:167, paragraph 46; judgment of 8 September 2011, Rosado Santana, C‑177/10, EU:C:2011:557, paragraph 56, and order of 9 February 2012, Lorenzo Martínez, C‑556/11, not published, EU:C:2012:67, paragraph 53).

60

In the light of all the foregoing considerations, the answer to the question referred is that clause 4(1) of the Framework Agreement must be interpreted as precluding national rules, such as those at issue in the main proceedings, which reserve participation in teaching evaluation plans and, in the case of a positive result, the ensuing financial incentives, exclusively for teachers employed under permanent employment relationships as established career civil servants, thereby excluding persons employed as interim civil servants under fixed-term employment relationships.

61

Since these proceedings are, for the parties to the main proceedings, a step in the action pending before the national court, the decision on costs is a matter for that court.

On those grounds, the Court (Tenth Chamber) hereby rules:

Clause 4(1) of the of the Framework agreement on fixed-term work, concluded on 18 March 1999, which is set out in the Annex to Council Directive 1999/70/EC of 28 June 1999 concerning the framework agreement on fixed-term work concluded by ETUC, UNICE and CEEP must be interpreted as precluding national rules, such as those at issue in the main proceedings, which reserve participation in teaching evaluation plans and, in the case of a positive result, the ensuing financial incentives, exclusively for teachers employed under permanent employment relationships as established career civil servants, thereby excluding persons employed as interim civil servants under fixed-term employment relationships.