The legal standing of electronic signatures (eSignatures) has been a recurring issue for businesses and authorities across the European Union (EU). A recent ruling by the Court of Justice of the European Union (ECJ) in 2024 brings important clarity, especially regarding the legal status of Qualified Electronic Signatures (QESs) under the eIDAS Regulation.
The Case: V.B. Trade vs. Bulgarian Tax Authority
A Bulgarian company, V.B. Trade (the “Company”), faced a corporate income tax adjustment, including interest charges. The tax authority used electronically signed documents as evidence of the Company’s tax liabilities. However, the Company challenged the validity of these eSignatures, arguing that they were insufficient to support the claims.
In response, the Bulgarian tax authority cited the eIDAS Regulation, asserting that electronic signatures cannot be legally disputed simply because they are electronic.
The case was then referred to the ECJ to address two key legal questions:
Key Legal Questions
- Can electronic signatures that meet eIDAS Regulation standards be challenged in court?
- Do national courts have the authority to question the evidential value of QESs in legal disputes?
ECJ’s Ruling
- eSignatures cannot be rejected for being electronic
The ECJ ruled that under the eIDAS Regulation, electronic signatures—whether Advanced Electronic Signatures (AdES) or QES—cannot be dismissed solely based on their digital nature.
→ This ruling affirms that eSignatures must be recognized as legally valid in legal and administrative proceedings across the EU.
- National courts can assess QESs similar to handwritten signatures
The ECJ clarified that while QESs have the same legal effect as handwritten signatures, national laws still play a role in evaluating their authenticity.
This means that if a country’s legal system allows challenges to handwritten signatures, the same scrutiny can be applied to QESs. This ensures consistency between digital and traditional signatures.

Implications of the Ruling
- Ensuring Fair Treatment of eSignatures
If a national court permits challenges to handwritten signatures—such as questioning their validity or origin—then QESs should be subject to the same legal challenge. This maintains a fair balance between electronic and traditional signatures within the EU’s legal framework.
- Greater Certainty for Businesses and Authorities
The ruling reinforces that QESs carry significant legal weight, providing businesses and public authorities with confidence when using electronic documents. However, they may still be challenged under the same conditions as handwritten signatures where national law permits.
- Role of Qualified Trust Service Providers (QTSPs)
This decision highlights the importance of QTSPs, which issue and manage qualified certificates for eSignatures. By complying with eIDAS’s strict security and verification standards, QTSPs help ensure that electronic transactions remain legally trustworthy.
Conclusion
The ECJ’s ruling marks a major step in harmonizing eSignature regulations across the EU. It strengthens legal certainty for digital transactions while allowing national courts to maintain their authority over assessing the validity of signatures.
As Europe continues its shift toward a digital-first economy, this decision reinforces the need for strong, reliable electronic identification and signature systems.