Banking Law and European Financial Sovereignty in Spain

Introduction

European financial sovereignty refers to the capacity of the European Union and its Member States, including Spain, to maintain a stable, resilient and independently functioning financial system while remaining integrated into international financial markets.

For Spain, financial sovereignty does not mean complete national control over banking. Spain participates in the euro area and the European Banking Union, meaning that important banking powers are exercised jointly or at EU level. Monetary policy is conducted through the Eurosystem; significant Spanish banks are subject to European Central Bank prudential supervision; and failing banks may come within the Single Resolution Mechanism.

The Spanish experience with Banco Popular Español provides an especially important example. Banco Popular was directly supervised by the ECB, and in June 2017 the Single Resolution Board adopted a resolution scheme that was endorsed by the European Commission. The subsequent litigation has helped define the distribution of authority among EU institutions, national courts, banks, shareholders and creditors.

Thus, European financial sovereignty in Spanish banking law is best understood as shared financial authority exercised through national and European institutions.

Legal and Regulatory Framework

1. EU Treaties and the Euro

Spain's financial sovereignty operates within the framework of the Treaty on European Union and the Treaty on the Functioning of the European Union.

As a euro-area Member State, Spain has transferred important monetary-policy functions to the European level. The European Central Bank determines euro-area monetary policy, while the Banco de España operates as part of the European System of Central Banks and the Eurosystem.

This arrangement limits purely national monetary autonomy but provides Spain with participation in a larger common monetary framework.

2. Single Supervisory Mechanism

Regulation (EU) No 1024/2013 established the Single Supervisory Mechanism.

The ECB directly supervises significant credit institutions, while national competent authorities—including the Banco de España—continue to perform important functions within the integrated supervisory system.

The Banco Popular litigation confirms the importance of this arrangement: Banco Popular was a Spanish credit institution under the ECB's direct prudential supervision when the resolution process occurred.

European financial sovereignty therefore involves centralized supervision designed to prevent weaknesses in one Member State's banking sector from threatening the wider euro area.

3. Single Resolution Mechanism

Regulation (EU) No 806/2014, the Single Resolution Mechanism Regulation, created a European framework for dealing with failing banks.

The Single Resolution Board may exercise important resolution powers where the statutory conditions are satisfied. The framework seeks to preserve critical banking functions and financial stability while limiting reliance on taxpayer-funded rescues.

Banco Popular became the first bank subjected to resolution under the SRM in 2017.

4. Bank Recovery and Resolution Directive

Directive 2014/59/EU (BRRD) provides the broader EU framework for recovery and resolution of credit institutions.

It establishes mechanisms including:

• recovery and resolution planning;
• write-down of capital instruments;
• bail-in;
• sale-of-business tools;
• protection of certain creditors;
• resolution authorities' powers; and
• safeguards concerning shareholders and creditors.

The Spanish Banco Popular litigation has repeatedly required the CJEU to interpret these rules.

5. Spanish Banking Legislation

At national level, Law 10/2014 on the organisation, supervision and solvency of credit institutions remains a central component of Spanish banking regulation.

Spain also implemented the European bank-recovery framework through Law 11/2015 on the recovery and resolution of credit institutions and investment firms.

Consequently, Spanish financial sovereignty operates through interaction between domestic legislation and directly applicable or harmonized European banking rules.

Main Dimensions of European Financial Sovereignty

Banking Supervision

Financial sovereignty requires authorities to identify excessive leverage, liquidity problems, weak governance and other prudential risks before they threaten financial stability.

Spain no longer performs this task entirely independently. Supervision is divided between European and Spanish authorities according to the Banking Union framework.

Bank Resolution

A financially sovereign system requires credible mechanisms for dealing with failing institutions.

The European resolution framework seeks to ensure that a major bank failure does not automatically require a national government bailout. Shareholders and certain creditors may instead absorb losses according to the resolution framework.

This is an important shift from national banking sovereignty toward collective European crisis-management sovereignty.

Payment Sovereignty

Another dimension concerns Europe's ability to maintain secure and resilient payment infrastructure.

Heavy dependence on infrastructure or service providers outside Europe may create strategic vulnerabilities. Consequently, European financial policy increasingly emphasizes resilient payment infrastructure, instant payments and European capacity in financial technology.

For Spanish banks, this means payment innovation increasingly operates within common EU regulatory standards.

Digital Euro

The proposed digital euro represents another aspect of European financial sovereignty. Its policy rationale includes preserving access to central-bank money as payments become increasingly digital and strengthening the resilience of Europe's payment environment.

For Spain, a future digital euro would operate alongside existing bank deposits and payment methods rather than constituting a separate Spanish currency.

Cybersecurity and Operational Resilience

Financial sovereignty also requires banks to remain operational during cyberattacks, technological failures and disruptions affecting third-party providers.

The Digital Operational Resilience Act (DORA) has created a common EU framework for ICT risk management, incident reporting, resilience testing and third-party technology risks across much of the financial sector.

For Spanish banks, operational sovereignty is therefore increasingly protected through common European standards.

Relevant Case Laws

1. Fundación Tatiana Pérez de Guzmán el Bueno and SFL v SRB — Case T-481/17

This case challenged the Single Resolution Board's decision concerning the resolution of Banco Popular.

In 2022, the General Court dismissed the challenge and examined important issues including resolution powers, property rights, the right to be heard and the conditions established by Regulation 806/2014.

Subsequent appeal proceedings clarified an important institutional point concerning the legal effects of the SRB scheme and the Commission's endorsement.

Relevance: The litigation illustrates how sovereignty over the failure of a major Spanish bank is exercised through EU institutions rather than exclusively by Spanish authorities.

2. Del Valle Ruiz and Others v Commission and SRB — Case T-510/17

Former investors challenged measures associated with Banco Popular's resolution.

The General Court dismissed the relevant annulment claims in its 1 June 2022 judgment.

Relevance: The case illustrates the judicial controls surrounding the exercise of European resolution authority and the relationship between financial stability and investor rights.

3. Eleveté Invest Group and Others v Commission and SRB — Case T-523/17

This was another major challenge arising from the Banco Popular resolution.

Together with the other Banco Popular cases, it required the General Court to examine the legality of the European resolution framework and the institutional decisions taken during the bank's failure. The challenges decided on 1 June 2022 were dismissed.

Relevance: European financial sovereignty remains subject to judicial review and fundamental-rights requirements.

4. Algebris (UK) and Anchorage Capital Group v Commission — Case T-570/17

Investors also challenged aspects of the Banco Popular resolution in this proceeding.

The case formed part of the group of judgments concerning the resolution scheme and the Commission's endorsement.

Relevance: It demonstrates the legal tension between centralized crisis-management powers and protection of private investors when authorities intervene in a failing bank.

5. Aeris Invest v Commission and SRB — Case T-628/17

Aeris Invest brought another challenge concerning Banco Popular's resolution.

The General Court considered the European resolution framework as part of the group of Banco Popular judgments delivered in June 2022.

Relevance: The case illustrates how the Banking Union combines strong resolution authority with access to judicial review before EU courts.

6. Banco Santander v J.A.C. and M.C.P.R. — Case C-410/20, Judgment of 5 May 2022

This CJEU case concerned investors who had acquired shares in Banco Popular before its resolution and subsequently sought remedies relating to allegedly incorrect prospectus information.

The Court considered the interaction between investor remedies and the BRRD rules governing write-down and resolution.

Relevance: The decision demonstrates that resolution law can significantly alter ordinary corporate and investor-remedy rules when necessary to give effect to a European bank-resolution measure.

7. M.S.G. and Others v Banco Santander — Joined Cases C-775/22, C-779/22 and C-794/22, Judgment of 5 September 2024

These proceedings also arose from Banco Popular.

They concerned subordinated instruments that were converted into shares and then transferred in the course of resolution. The CJEU examined BRRD provisions concerning bail-in, write-down, shareholder and creditor rights, and claims based on allegedly defective prospectus information.

Relevance: The judgment demonstrates how EU resolution law can determine the consequences of investments originally created under national private and securities law.

8. D.E. v Banco Santander — Case C-687/23, Judgment of 11 September 2025

This more recent Spanish reference again concerned Banco Popular's resolution and investor claims involving allegedly defective or incorrect prospectus information.

The CJEU examined BRRD provisions on bail-in, write-down of capital instruments, shareholder and creditor protection, actions for nullity and damages, including claims initiated before resolution measures were adopted.

Relevance: The judgment further clarifies the consequences of EU resolution decisions for private-law claims before Spanish courts.

Financial Sovereignty and National Autonomy

European financial sovereignty produces an important constitutional and regulatory balance.

Spain retains national institutions including the Banco de España, national courts, financial regulators and national legislation. However, important decisions involving monetary policy, significant-bank supervision and bank resolution are embedded within European structures.

Therefore, sovereignty has not simply disappeared. Instead, important financial powers are exercised through a multi-level system.

For example, the ECB may perform supervisory functions, the SRB may formulate resolution measures, the European Commission may exercise functions assigned to it by the SRM framework, Spanish authorities implement relevant measures, and EU and Spanish courts resolve disputes within their respective jurisdictions.

The Banco Popular litigation is particularly significant because it exposes this institutional structure in practice. The dispute generated extensive litigation over the roles and legal responsibilities of the SRB and Commission.

Advantages and Legal Challenges

European financial sovereignty can strengthen Spain's capacity to respond to cross-border banking crises. Common supervision reduces the risk that national authorities apply materially inconsistent standards to major euro-area banks, while common resolution rules provide mechanisms for handling failing institutions without relying exclusively on national public finances.

However, centralized authority creates legal challenges concerning accountability, transparency, judicial review, property rights, creditor protection and the division of powers between EU and national authorities.

The Banco Popular cases demonstrate these tensions particularly clearly. The courts have had to examine both the effectiveness of the resolution framework and the procedural and substantive rights of investors affected by resolution measures.

Conclusion

Banking law and European financial sovereignty in Spain reflect the transformation of traditional national banking sovereignty into a shared European regulatory system.

Spain retains substantial responsibility for its domestic financial system, but the most important systemic functions increasingly operate through European institutions. Monetary policy is integrated through the Eurosystem; significant banks are supervised through the Single Supervisory Mechanism; failing banks may be handled through the Single Resolution Mechanism; and Spanish banking legislation operates within the BRRD and broader EU regulatory framework.

The Banco Popular litigation provides the clearest practical illustration. Cases including Fundación Tatiana Pérez de Guzmán, Del Valle Ruiz, Eleveté Invest, Algebris, Aeris Invest, Banco Santander v J.A.C., M.S.G. v Banco Santander, and D.E. v Banco Santander show how European resolution powers interact with Spanish banking relationships, shareholder rights, creditor protection and national litigation.

Accordingly, European financial sovereignty in Spain can be understood through four central objectives: financial stability, effective European banking supervision, credible crisis resolution, and resilient European financial infrastructure. The Spanish model demonstrates that modern financial sovereignty is no longer purely national; it is exercised jointly through Spanish and European legal institutions.