–

Santander Renta Variable España Pensiones, Fondo de Pensiones, by M.F. Cabral Matos, T. Marreiros Moreira and R. Pereira de Abreu, advogados,

–

the Portuguese Government, by P. Barros da Costa, H. Gomes Magno and A. Rodrigues, acting as Agents,

–

the European Commission, by P. Caro de Sousa and W. Roels, acting as Agents,

1

This request for a preliminary ruling concerns the interpretation of Article 63 TFEU.

2

The request has been made in proceedings between Santander Renta Variable España Pensiones, Fondo de Pensiones (‘Santander’), and the Autoridade Tributária e Aduaneira (Tax and Customs Authority, Portugal; ‘the tax authority’), concerning the lawfulness of the taxation of dividends received by Santander, relating to the years 2020 and 2021, by way of a final withholding at source.

3

Article 10(1) and (2) of the Convention between the Portuguese Republic and the Kingdom of Spain for the avoidance of double taxation and the prevention of tax evasion in the field of income tax, concluded in Madrid on 26 October 1993, provides:

‘1.   Dividends paid by a company which is a resident of a Contracting State to a resident of the other Contracting State may be taxed in that other State.

2.   Those dividends may nevertheless be taxed in the Contracting State of which the company paying the dividends is a resident and according to the laws of that State, but if the recipient of the dividends is their beneficial owner, the tax so charged may not exceed:

…

(b) 15% of the gross amount of the dividends in all other cases.

…’

4

Article 63(1) TFEU provides:

‘Within the framework of the provisions set out in this Chapter, all restrictions on the movement of capital between Member States and between Member States and third countries shall be prohibited.’

5

Article 65 TFEU provides:

‘1.   The provisions of Article 63 shall be without prejudice to the right of Member States:

…

3.   The measures and procedures referred to in paragraphs 1 and 2 shall not constitute a means of arbitrary discrimination or a disguised restriction on the free movement of capital and payments as defined in Article 63.

…’

6

Recital 3 of Directive (EU) 2016/2341 of the European Parliament and of the Council of 14 December 2016 on the activities and supervision of institutions for occupational retirement provision (IORPs) (OJ 2016 L 354, p. 37) states:

‘This Directive is aimed at minimum harmonisation and therefore should not preclude Member States from maintaining or introducing further provisions in order to protect members and beneficiaries of occupational pension schemes, provided that such provisions are consistent with Member States’ obligations under Union law. This Directive does not concern issues of national social, labour, tax or contract law, or the adequacy of pension provision in Member States.’

7

Article 6 of that directive provides:

‘For the purposes of this Directive:

…

…’

8

Under Article 45 of that directive:

‘1.   The main objective of prudential supervision is to protect the rights of members and beneficiaries and to ensure the stability and soundness of the [institutions for occupational retirement provision (IORPs)].

2.   Member States shall ensure that the competent authorities are provided with the necessary means, and have the relevant expertise, capacity, and mandate to achieve the main objective of supervision referred to in paragraph 1.’

9

Article 50(a) of Directive 2016/2341 provides:

‘Member States shall ensure that the competent authorities, in respect of any IORP registered or authorised in their territories, have the necessary powers and means to:

…’

10

Recital 7 of Council Directive 2010/24/EU of 16 March 2010 concerning mutual assistance for the recovery of claims relating to taxes, duties and other measures (OJ 2010 L 84, p. 1), states:

‘Mutual assistance may consist of the following: the requested authority may supply the applicant authority with the information which the latter needs in order to recover claims arising in the applicant Member State and notify to the debtor all documents relating to such claims emanating from the applicant Member State. The requested authority may also recover, at the request of the applicant authority, the claims arising in the applicant Member State, or take precautionary measures to guarantee the recovery of these claims.’

11

Pursuant to Article 1 thereof, that directive lays down the rules under which the Member States are to provide assistance for the recovery in a Member State of any claims referred to in Article 2 which arise in another Member State.

12

Article 2(1)(a) of that directive provides:

‘This Directive shall apply to claims relating to the following:

13

Article 5(1) of that directive is worded as follows:

‘At the request of the applicant authority, the requested authority shall provide any information which is foreseeably relevant to the applicant authority in the recovery of its claims as referred to in Article 2.

For the purpose of providing that information, the requested authority shall arrange for the carrying-out of any administrative enquiries necessary to obtain it.’

14

Article 10(1) of Directive 2010/24 provides:

‘At the request of the applicant authority, the requested authority shall recover claims which are the subject of an instrument permitting enforcement in the applicant Member State.’

15

Article 1(1) of Council Directive 2011/16/EU of 15 February 2011 on administrative cooperation in the field of taxation and repealing Directive 77/799/EEC (OJ 2011 L 64, p. 1) provides:

‘This Directive lays down the rules and procedures under which the Member States shall cooperate with each other with a view to exchanging information that is foreseeably relevant to the administration and enforcement of the domestic laws of the Member States concerning the taxes referred to in Article 2.’

16

Article 2(1) of Directive 2011/16 provides that that directive is to apply to all taxes of any kind levied by, or on behalf of, a Member State or the Member State’s territorial or administrative subdivisions, including the local authorities.

17

Chapter II of that directive includes Section I thereof, entitled ‘Exchange of information on request’, which in turn contains Article 5 of that directive; that article provides:

‘At the request of the requesting authority, the requested authority shall communicate to the requesting authority any information referred to in Article 1(1) that it has in its possession or that it obtains as a result of administrative enquiries.’

18

Article 16 of the Estatuto dos Benefícios Fiscais (Statute governing tax benefits) (Diário da República, I Series I-A, No 149, of 1 July 1989), in the version applicable to the dispute in the main proceedings (‘the EBF’), entitled ‘Pension funds and similar entities’, is worded as follows:

‘1.   The income of pension funds and similar entities that are constituted and that operate in accordance with national law shall be exempt from [corporation tax].

…

7.   The income of pension funds that are constituted in, operate in accordance with the law of, and are established in another Member State of the European Union or of the European Economic Area – in the latter case, provided that the Member State in question is bound by a system of administrative cooperation in the field of taxation equivalent to that established within the European Union – and which income is not attributable to a permanent establishment located in Portuguese territory, shall be exempt from [corporation tax], provided that the pension funds satisfy the following cumulative requirements:

8.   Without prejudice to Article 98 of the [Código do Imposto sobre o Rendimento das Pessoas Coletivas (Corporation Tax Code), approved by Decreto-Lei n. 442-B/88 (Decree-Law No 442-B/88) of 30 November 1988 (Diário da República, Series I, No 277, of 30 November 1988) (‘the CIRC’)], in order for the provisions of the preceding paragraph to be immediately applicable, proof that the conditions laid down in paragraph 7(a), (b) and (c) of the present Article have been satisfied must be provided to the entity required to withhold tax at source, prior to the date on which the income is made available, by means of a declaration confirmed and certified by the authorities of the Member State of the European Union or of the European Economic Area that are responsible for the supervision in question.’

19

Article 98(5) and (7) of the CIRC provides:

‘5.   Without prejudice to the provisions of the following paragraph, where the proof has not been provided before the expiry of the period stipulated for payment of the tax, and also in the cases referred to in Article 14(3) et seq., the substitute taxpayer shall be required to pay the full amount of the tax that should have been deducted pursuant to the law.

…

7.   Where proof has not been provided within the prescribed period and under the conditions laid down, the entities that are beneficiaries of the income and that satisfy the conditions referred to in paragraphs 1 and 2 of the present Article and in Article 14(3) et seq. may request a full or partial refund of the tax withheld at source, within two years of the end of the year in which the chargeable event occurred, by submitting a standard form approved by decree of the member of the Government responsible for finance, accompanied by a document issued by the competent authorities of the relevant State of residence, attesting to the tax residence of those entities during the period in question and their liability to income tax in that State.’

20

Santander is a legal person governed by Spanish law, constituted as a pension fund established under contract law and resident for tax purposes in Spain.

21

In 2020 and 2021, Santander, which did not have a permanent establishment in Portugal, received dividends in respect of shares held continuously for at least one year in companies resident in Portugal. Those dividends were subject to corporation tax at a rate of 25%, levied by way of a final withholding at source.

22

After requesting a refund of the difference between the amount of the tax thus levied and the amount corresponding to the tax rate of 15% laid down in the Convention between the Portuguese Republic and the Kingdom of Spain for the avoidance of double taxation and the prevention of tax evasion in the field of income tax, concluded in Madrid on 26 October 1993, Santander sought, first, that the acts withholding at source the corporation tax for the years 2020 and 2021 be annulled on the ground of an infringement of EU law and, second, that its right to a refund of the total amount of the tax, withheld in error in respect of those years, be recognised, asserting that it had satisfied all the conditions laid down in Article 16 of the EBF.

23

The Tribunal Arbitral Tributário (Centro de Arbitragem Administrativa) (Tax Arbitration Tribunal (Centre for Administrative Arbitration), Portugal), which is the referring court, notes that Article 16 of the EBF, in the version applicable in 2020 and 2021, was adopted following the judgment of 6 October 2011, Commission v Portugal (C‑493/09, EU:C:2011:635), and that the exemption of non-resident pension funds has been subject, since 2012, to the same conditions as those applicable to resident pension funds.

24

The referring court states, first, that, in order for income received in Portugal to benefit immediately from the exemption from corporation tax, non-resident pension funds must provide, prior to the date on which the income is made available, proof that the conditions laid down in Article 16(7)(a), (b) and (c) of the EBF are satisfied, by means of the declaration referred to in Article 16(8) of the EBF.

25

The referring court states, second, that it follows from a combined reading of Article 16(8) of the EBF and Article 98 of the CIRC that pension funds resident in another Member State that have not enjoyed the exemption from corporation tax may request a refund of the tax withheld in error in Portugal, provided that they establish that the substantive conditions laid down in Article 16 of the EBF are satisfied.

26

The referring court notes that Santander claims to have tried, without success, to obtain the declaration referred to in Article 16(8) of the EBF; that court considers that, since the requirements under Portuguese law cannot be relied on against another Member State, Santander cannot require the entity responsible for its supervision in Spain to issue certificates containing information which that entity might not be empowered to issue, under its own legislation and internal rules.

27

Therefore, the referring court is uncertain, in the light, in particular, of the judgment of 6 October 2011, Commission v Portugal (C‑493/09, EU:C:2011:635, paragraph 49), whether the conditions relating to proof, as laid down in Article 16(7) and (8) of the EBF, may be imposed on non-resident pension funds, especially where they are not required of a resident pension fund, and whether, in a situation where the taxpayer claims that it is unable to obtain such proof, the tax authority must request that proof of its own motion.

28

In those circumstances, the Tribunal Arbitral Tributário (Centro de Arbitragem Administrativa) (Tax Arbitration Tribunal (Centre for Administrative Arbitration)) decided to stay the proceedings and to refer the following questions to the Court of Justice for a preliminary ruling:

29

First, without formally calling into question the admissibility of the request for a preliminary ruling, the Portuguese Government disputes the premiss on which the referring court relies, that is to say, that the burden of proof imposed by Article 16(7) and (8) of the EBF, read in conjunction with Article 98 of the CIRC, has the effect of preventing the non-resident pension fund from exercising its right to exemption from corporation tax. That government asserts, in essence, that all means of proof capable of attesting to the fact that the conditions laid down in Article 16(7) of the EBF are satisfied are permitted and that the non-application of that exemption in the situation at issue in the main proceedings is the consequence of the actions of the Portuguese company distributing dividends and of the actions of the non-resident pension fund in receipt of those dividends, which should, in particular, have properly made their legal claims.

30

In that regard, it must be noted that, in proceedings under Article 267 TFEU, the Court must take account, under the division of jurisdiction between the Courts of the European Union and the national courts, of the factual and legislative context, which the referring court is responsible for defining, in which the questions put to it are set (see, to that effect, judgment of 27 February 2025, Dyrektor Krajowej Informacji Skarbowej (Management form of a UCI), C‑18/23, EU:C:2025:119, paragraph 36 and the case-law cited).

31

Furthermore, the question whether or not the premisses relied on by the referring court in its questions are incorrect is a question relating to the factual context, the accuracy of which is not a matter for the Court to determine (judgment of 27 February 2025, Dyrektor Krajowej Informacji Skarbowej (Management form of a UCI), C‑18/23, EU:C:2025:119, paragraph 37 and the case-law cited).

32

The Portuguese Government is therefore not entitled to call into question before the Court of Justice the premisses arising from the national and factual context, as accepted by the referring court, on which the Court must base its answer to the questions referred for a preliminary ruling.

33

Second, in so far as the European Commission is uncertain as regards the substantive conditions laid down in Article 16(7) of the EBF, it must be noted that the examination of the conformity with EU law of the conditions relating to proof that a non-resident pension fund must satisfy in order to be granted an exemption from corporation tax is relevant only if the substantive conditions are themselves consistent with EU law. As is apparent from the request for a preliminary ruling, the referring court considers that, as from 2012, that exemption, when it concerns income received in Portugal by pension funds resident in another EU Member State, is subject to the same substantive conditions as those applicable to pension funds constituted in accordance with Portuguese law.

34

Since the referring court is asking the Court of Justice only about the interpretation of EU law with regard to the conditions relating to proof that are applicable to non-resident pension funds, it is necessary for the Court to rule on that matter alone, without taking a position, in the present case, on the interpretation of EU law in relation to the substantive conditions applicable to non-resident pension funds for the purpose of being granted an exemption from corporation tax.

35

By its first question, the referring court asks, in essence, whether Article 63(1) TFEU must be interpreted as precluding a Member State from requiring a non-resident pension fund to provide proof that the substantive conditions for being granted an exemption from the tax levied on dividends received by that fund, or for being granted a refund of that tax, have been satisfied, by producing a declaration that is confirmed and certified by the authorities responsible for the supervision of that fund in its Member State of residence.

36

It follows from settled case-law of the Court that the measures prohibited by Article 63(1) TFEU, as restrictions on the movement of capital, include those that are such as to discourage non-residents from making investments in a Member State or to discourage that Member State’s residents from doing so in other States (judgments of 6 October 2011, Commission v Portugal, C‑493/09, EU:C:2011:635, paragraph 28, and of 7 November 2024, XX (Unit-linked contracts), C‑782/22, EU:C:2024:932, paragraph 28 and the case-law cited).

37

The examination of the deterrent nature of the measures may cover not only measures establishing substantive conditions in order to be able to benefit from a tax advantage, but also measures providing for the proof to be supplied by non-resident taxpayers for that purpose (see, to that effect, judgment of 30 January 2020, Köln-Aktienfonds Deka, C‑156/17, EU:C:2020:51, paragraph 50).

38

In the present case, it is apparent from the request for a preliminary ruling that, in order to enjoy the exemption from corporation tax, a non-resident pension fund must, in accordance with Article 16(8) of the EBF, provide, prior to the date on which the income concerned is made available, the entity required to withhold tax at source with proof that the conditions laid down in Article 16(7)(a), (b) and (c) are satisfied, by means of a declaration that is confirmed and certified by the authorities of the Member State of the European Union or of the European Economic Area that are responsible for the supervision of that fund, whereas a resident pension fund is not required to satisfy those conditions.

39

It follows from that that non-resident pension funds are subject, in order to enjoy the exemption from corporation tax or in order to obtain a refund of that tax, to administrative burdens to which resident pension funds are not subject.

40

Such a difference in treatment amounts to unfavourable treatment of non-resident pension funds, liable to deter them from making investments in Portuguese companies, and, consequently, constitutes a restriction on the free movement of capital prohibited, in principle, by Article 63(1) TFEU.

41

That being said, under Article 65(1)(a) TFEU, Article 63 TFEU is to be without prejudice to the right of Member States to apply the relevant provisions of their tax law which distinguish between taxpayers who are not in the same situation with regard to their place of residence or with regard to the place where their capital is invested.

42

It is apparent from settled case-law that Article 65(1)(a) TFEU, in so far as it is a derogation from the fundamental principle of the free movement of capital, must be interpreted strictly. That provision cannot therefore be interpreted as meaning that all tax legislation which draws a distinction between taxpayers based on their place of residence or the State in which they invest their capital is automatically compatible with the FEU Treaty (judgments of 17 January 2008, Jäger, C‑256/06, EU:C:2008:20, paragraph 40, and of 27 February 2025, Dyrektor Krajowej Informacji Skarbowej (Management form of a UCI), C‑18/23, EU:C:2025:119, paragraph 76 and the case-law cited).

43

The differences in treatment permitted by Article 65(1)(a) TFEU must not constitute, according to Article 65(3) TFEU, a means of arbitrary discrimination or a disguised restriction. The Court has held, consequently, that such differences in treatment are permitted only when they concern situations which are not objectively comparable or, otherwise, when they are justified by an overriding reason in the public interest (judgments of 6 June 2000, Verkooijen, C‑35/98, EU:C:2000:294, paragraph 43, and of 27 February 2025, Dyrektor Krajowej Informacji Skarbowej (Management form of a UCI), C‑18/23, EU:C:2025:119, paragraph 77 and the case-law cited).

44

It follows from the Court’s case-law, first, that the comparability or otherwise of a cross-border situation with a domestic situation must be examined having regard to the objective pursued by the national legislation at issue and to the purpose and content of that legislation, and, second, that only the relevant distinguishing criteria established by that legislation must be taken into account for the purpose of assessing whether the difference in treatment resulting from such legislation reflects a difference in objective situation (judgments of 29 April 2021, Veronsaajien oikeudenvalvontayksikkö (Income paid by UCITS), C‑480/19, EU:C:2021:334, paragraph 49, and of 7 November 2024, XX (Unit-linked contracts), C‑782/22, EU:C:2024:932, paragraph 45 and the case-law cited).

45

That is why, as soon as a Member State, either unilaterally or by way of a convention, imposes a charge to tax on the income not only of resident taxpayers but also of non-resident taxpayers from dividends which they receive from a resident company, the Court considers that the situation of those non-resident taxpayers becomes comparable to that of resident taxpayers (judgments of 12 December 2006, Test Claimants in Class IV of the ACT Group Litigation, C‑374/04, EU:C:2006:773, paragraph 68, and of 19 December 2024, Credit Suisse Securities (Europe), C‑601/23, EU:C:2024:1048, paragraph 53 and the case-law cited).

46

In the present case, the legislation at issue in the main proceedings recognises that the situation of resident pension funds and that of non-resident pension funds are comparable, since non-resident pension funds, like resident pension funds, enjoy the exemption from the tax levied on dividends they receive. Nevertheless, it makes those two categories of funds subject to different treatment as regards the proof that they satisfy the substantive conditions so as to benefit from that exemption. Both resident and non-resident pension funds need to satisfy the substantive conditions in order to obtain a tax advantage.

47

Consequently, legislation the purpose of which is to ensure that the substantive conditions for a tax advantage are satisfied and which imposes conditions for proving that that is the case solely on non-resident pension funds does not reflect an objective difference in the situation of resident pension funds and that of non-resident pension funds.

48

It must therefore be ascertained whether the difference in treatment resulting from the legislation at issue in the main proceedings may be justified by an overriding reason in the public interest.

49

In that regard, it is clear from settled case-law that the need to guarantee the effectiveness of fiscal supervision and the need to ensure the effective collection of tax constitute overriding reasons in the public interest capable of justifying a restriction on the free movement of capital, provided that it is suitable for securing, in a consistent and systematic manner, the attainment of those objectives and does not go beyond what is necessary in order to attain them (see, to that effect, judgments of 12 October 2023, BA (Inheritance – Public housing policy in the European Union), C‑670/21, EU:C:2023:763, paragraphs 67 and 78 and the case-law cited, and of 19 December 2024, Credit Suisse Securities (Europe), C‑601/23, EU:C:2024:1048, paragraph 59 and the case-law cited).

50

Although it is ultimately for the referring court, which has sole jurisdiction to assess the facts of the main proceedings and interpret the national legislation, to determine whether and to what extent such legislation satisfies those conditions, the Court of Justice, which is called on to provide answers of use to that court, may provide guidance based on the documents relating to the main proceedings and on the written observations which have been submitted to it, in order to enable the court in question to give judgment (judgment of 7 September 2022, Cilevičs and Others, C‑391/20, EU:C:2022:638, paragraphs 72 and 73 and the case-law cited).

51

In the present case, in order to enjoy the exemption from corporation tax or in order to obtain a refund of that tax, the non-resident pension fund must provide a declaration that is confirmed and certified by the authorities responsible for its supervision in its Member State of residence, demonstrating, first, that that fund guarantees, exclusively, the payment of pension benefits on grounds of old age or invalidity, survivors’ pensions, pre-retirement or early retirement benefits, post-employment healthcare benefits and, where they are supplementary or ancillary to those benefits, the payment of death grants, second, that it is managed by institutions for occupational retirement provision to which Directive 2003/41 applies and, third, that it is the beneficial owner of the income.

52

In that respect, as regards the suitability of such a declaration for securing, in a consistent and systematic manner, the attainment of the objectives referred to in paragraph 49 above, it is important to recall that the tax authorities of a Member State are entitled to require the taxpayer to provide such proof as they may consider necessary in order to determine whether the conditions for granting a tax advantage have been met and, consequently, whether or not to grant that advantage. The content, the form and the degree of detail which the information submitted by the taxpayer must satisfy are determined by the Member State conferring such an advantage in order to enable it to levy the tax properly (see, to that effect, judgment of 30 January 2020, Köln-Aktienfonds Deka, C‑156/17, EU:C:2020:51, paragraph 61 and the case-law cited).

53

Nevertheless, in order not to make it impossible or excessively difficult for a non-resident taxpayer to obtain a tax advantage, that person cannot be required to produce documents which comply in all respects with the form and degree of detail of the documentary evidence laid down in the national legislation of the Member State conferring that advantage if the documents provided by that taxpayer do enable that Member State to ascertain, clearly and precisely, that the conditions for obtaining the tax advantage in question have been met. Non-resident taxpayers may not be subject to excessive administrative burdens that make it in fact impossible for them to benefit from a tax advantage (see, to that effect, judgment of 30 January 2020, Köln-Aktienfonds Deka, C‑156/17, EU:C:2020:51, paragraph 62 and the case-law cited).

54

It follows from that that the condition, applied only to non-resident pension funds, requiring the submission of a declaration, such as that provided for by the legislation at issue in the main proceedings, issued by the authorities of another Member State, is suitable for securing, in a consistent and systematic manner, the effectiveness of fiscal supervision and the effective collection of tax only if those authorities have the necessary powers and competences to issue such a declaration and if that declaration may be issued to the pension fund concerned within a reasonable period of time.

55

In that regard, it is important to note that Directive 2016/2341, which repealed, with effect from 13 January 2019, Directive 2003/41, defines, in Article 6(1) and (4) thereof, the concepts of ‘institution for occupational retirement provision’ and ‘retirement benefits’ in a manner that is in essence identical to the corresponding concepts in Directive 2003/41, to which Article 16(7) of the EBF refers.

56

Although Article 50(a) of Directive 2016/2341 provides that Member States are to ensure that the competent authorities have, in respect of any IORP registered or authorised in their territory, the necessary powers and means to require the IORP, the administrative, management or supervisory body thereof or the persons who effectively run it or carry out key functions to supply at any time information about all business matters or forward all business documents, that directive contains no provision laying down a right on the part of pension funds to request those authorities to issue declarations such as those required by the legislation at issue in the main proceedings, nor any provision conferring on those authorities the power to issue such declarations.

57

Since, in accordance with recital 3 thereof, Directive 2016/2341 is aimed only at minimum harmonisation, the possibility of obtaining such a declaration is dependent on the national legislation of the State of residence of the pension fund seeking a tax exemption.

58

In the present case, if the referring court were to find that the supervisory authorities of the State of residence of the pension fund that is the applicant in the main proceedings do not have the powers and competences necessary to issue a declaration such as that required by the legislation at issue in the main proceedings or that that declaration cannot be issued within a reasonable period of time, it would have to be considered that the requirement to submit a declaration issued by those authorities is not suitable for securing, in a consistent and systematic manner, compliance with the substantive conditions for being granted the tax advantage and, more broadly, the effectiveness of fiscal supervision and the effective collection of tax.

59

If that is not the case, it must still be determined whether such a requirement goes beyond what is necessary to attain those objectives.

60

That examination must be carried out by distinguishing the two situations to which the referring court points, namely, on the one hand, the immediate exemption from the withholding at source of corporation tax and, on the other, the subsequent refund of the withholding tax levied.

61

In the first place, as regards the exemption from the withholding of that tax at source, it is apparent from Article 16(8) of the EBF that, in order for that exemption to be granted, proof that the conditions laid down in Article 16(7)(a), (b) and (c) of the EBF are satisfied must be provided, prior to the date on which the income is made available to non-resident pension funds, to the entity required to withhold that tax at source. The entities that are required to withhold the tax at source are, in the present case, Portuguese resident companies in which non-resident pension funds hold shares. It follows that it is those resident companies that must be able to verify that the non-resident pension fund at issue in the main proceedings satisfies the substantive conditions for being exempt from withholding tax.

62

In that regard, it is important that the entity in question that is required to withhold the tax at source cannot consider itself relieved of its obligation to do so unless it is certain that the recipient of dividends satisfies the conditions allowing it to enjoy an exemption from that tax. The entity paying the dividends may not be required to ensure, through means of proof that meet criteria other than those provided by the national legislation to which that person is subject, that the dividends in question satisfy the substantive conditions for being exempt from withholding tax, at the risk of compromising, in the event of an error on its part, the collection of the tax from the recipient of the dividends (see, to that effect, judgment of 3 October 2006, FKP Scorpio Konzertproduktionen, C‑290/04, EU:C:2006:630, point 60).

63

Consequently, assuming that it is suitable for securing the effectiveness of fiscal supervision and the effective collection of tax, the obligation for a non-resident pension fund to provide the resident companies which pay the dividends with a declaration that is confirmed and certified by the authorities responsible for the supervision of that fund in its Member State of residence does not go beyond what is necessary in order to attain those objectives.

64

It will be for the referring court to ascertain whether the legislation at issue in the main proceedings observes the principle of proportionality in the strict sense, by not being disproportionate to the objectives pursued, having regard to the fact, referred to by the Portuguese Government in its written observations submitted to the Court of Justice, that the tax authority would accept any document as a means of proving that the conditions laid down in Article 16(7) of the EBF have been satisfied, provided that it is accompanied by a document issued by the competent authorities of the State of residence of the non-resident pension fund concerned, attesting to that fund’s residence for tax purposes and its being liable to income tax in that State.

65

In the second place, as regards the refund of the tax levied, if the referring court were to consider, following the examination referred to in paragraph 58 above, that the requirement to submit to the tax authorities of the Member State in which the dividends are paid a declaration issued by the supervisory authorities of the Member State where the non-resident pension fund is resident for tax purposes is suitable for attaining the objectives pursued, it would have to ascertain whether that requirement goes beyond what is necessary in order to attain them.

66

In that regard, the Court has previously held that legislation of a Member State which indiscriminately prevents taxpayers from adducing evidence which satisfies criteria, in particular those of presentation, other than those laid down by that legislation, goes beyond what is necessary to guarantee the effectiveness of fiscal supervision and the effective collection of tax (see, to that effect, judgments of 30 June 2011, Meilicke and Others, C‑262/09, EU:C:2011:438, paragraph 43, and of 9 October 2014, van Caster, C‑326/12, EU:C:2014:2269, paragraph 49).

67

Unlike the situation examined in paragraphs 61 to 64 above, in which the company distributing the dividends is responsible for withholding the tax, it is in this case the tax authority of the Member State in which the dividends are paid which must decide on the application for a refund of that withholding tax. Such an authority may use mutual assistance mechanisms existing between the authorities of the Member States that are sufficient to enable the Member State in which the dividends are paid to check the accuracy of the evidence put forward by non-resident companies wishing to claim reimbursement of the withholding tax (judgment of 19 December 2024, Credit Suisse Securities (Europe), C‑601/23, EU:C:2024:1048, paragraph 65 and the case-law cited).

68

Thus, Article 5, read in conjunction with Article 1(1) and Article 2, of Directive 2011/16, which, in accordance with Article 28 thereof, repealed Directive 77/799 with effect from 1 January 2013, provides that, at the request of the requesting authority, the requested authority is to communicate to the requesting authority the information that is foreseeably relevant to the administration and application of the domestic law of the Member State to which the requested authority is subject, concerning the taxes coming within the scope of Directive 2011/26, that it has in its possession or that it obtains as a result of administrative enquiries.

69

Article 5 of Directive 2011/16 is part of Section I of Chapter II of that directive; that section concerns the exchange of information on request, in the context of which that directive organises the relationship between the requesting Member State and the requested Member State and their reciprocal obligations (judgment of 26 September 2024, Ordre des avocats du Barreau de Luxembourg, C‑432/23, EU:C:2024:791, paragraph 56).

70

Although no provision of Directive 2011/16 imposes an obligation on the authorities of a Member State to make the request referred to in Article 5 thereof, since, for the purposes of the exchange of information on request provided for by that directive, the EU legislature has merely determined the obligations which the Member States have towards each other (see, to that effect, judgment of26 September 2024, Ordre des avocats du Barreau de Luxembourg, C‑432/23, EU:C:2024:791, paragraph 59), that directive allows a Member State to request from the competent authorities of another Member State any information such as to enable it properly to set income taxes.

71

Consequently, as regards the refund of corporation tax levied by means of a withholding at source, the requirement to submit a declaration issued by the authorities responsible for the supervision of the non-resident pension fund, as the sole means of proof, goes beyond what is necessary to attain the objectives pursued.

72

In the light of all the foregoing considerations, the answer to the first question referred for a preliminary ruling is that Article 63(1) TFEU must be interpreted as:

73

In the light of the answer to the first question, there is no need to answer the second question referred for a preliminary ruling.

74

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.

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

Article 63(1) TFEU must be interpreted as: