Digital Signatures in International Contracts: validity, risks, and drafting best practices

Introduction

More and more international contracts today are signed without the parties being in the same room – often not even on the same continent. Platforms such as (to name just a few) DocuSign, Adobe Sign, or YouSign have made the electronic signature the standard tool for concluding cross-border commercial agreements.

Yet behind the simplicity of the gesture – a click, an OTP code, a stroke on a tablet – lies significant legal complexity. The question every professional should ask is: is that electronic signature valid in all the jurisdictions involved in the contract?

The answer, as we will see, is not obvious. And a well-drafted electronic signature clause can make the difference between an effective agreement and litigation over form.

The Regulatory Framework: A Mosaic of Rules

The first obstacle is the fragmentation of supranational and national rules. Let’s look at the main ones.

eIDAS Regulation (EU No 910/2014). In the European Union, the eIDAS Regulation – a primary source of law directly applicable in all Member States – distinguishes three levels of signature: the simple electronic signature – SES (whose evidentiary value is freely assessed by the judge), the advanced electronic signature – AES (guarantees unique identification of the signatory and the link to the signed data, but does not in itself confer a certain date) and the qualified electronic signature – QES (based on a qualified certificate, created through a secure device). Only the latter enjoys, under Article 25(2) eIDAS, automatic legal equivalence to a handwritten signature in all Member States, with a date enforceable against third parties if associated with a so-called qualified timestamp.

Public registers of Qualified Trust Service Providers (QTSP) exist: in Italy the trusted list is managed by AgID, while the European list is the EUTL. Registration qualifies the provider and its related services.

Italian law. The Digital Administration Code (Legislative Decree No. 82/2005) recognizes, alongside the eIDAS categories, an autonomous type of signature: the “firma digitale” (“digital signature”), a qualified electronic signature with the distinctive feature of being based on public-key cryptography (PKI).

French law. Article 1367 of the Code civil treats the electronic signature as equivalent to a handwritten one if the process identifies the signatory and guarantees the integrity of the document; eIDAS strengthens the framework for qualified signatures.

Notes on other non-EU jurisdictions. In Hong Kong, the Electronic Transactions Ordinance adopts a functional approach: the electronic signature is generally accepted, but with significant exclusions for certain categories of acts (for example, wills, powers of attorney, real estate transfers), following a model typical of common law jurisdictions. In the United States, the ESIGN Act and UETA adopt a technology-neutral approach; in the United Kingdom, the Law Commission recognizes its validity for contracts generally even after Brexit.

The Heart of the Matter: Private International Law Issues

Italy presents a notable peculiarity.

As illustrated in one of our recent contributions on unfair contract terms (“clausole vessatorie“), Articles 1341 and 1342 of the Civil Code require the specific written approval of certain onerous clauses, even in business-to-business relationships. With Order No. 20945/2026, the Court of Cassation confirmed that this requirement applies to digital contracting: an electronic signature may suffice if it allows for informed and specific approval – for example via an OTP code, not through a simple “checkbox” – and if proof of this is retained. The situation is different for contracts under Article 1350 of the Civil Code, for which written form is required ad substantiam, and the choice of signature level requires particular caution.

This is where the matter becomes truly tricky. In a multi-jurisdictional contract, which law governs the formal validity of the agreement?

Article 11 of the Rome I Regulation (EC No. 593/2008) establishes that a contract between parties located in different countries is formally valid if it satisfies the requirements of the law governing its substance, or of the law of one of the countries in which one of the parties is located. This alternative criterion, inspired by the principles of locus regit actum and favor negotii, broadens the possibilities for formal validity.

However, Article 9 of the Rome I Regulation independently governs overriding mandatory provisions (lois de police), which may prevail over the otherwise applicable law. For example, if a contract is governed by French law but includes clauses that, under Italian law, require specific written approval under Article 1341 of the Civil Code, an Italian judge could still apply that requirement as a mandatory rule. An unfair clause lacking the double signature could therefore be declared ineffective, regardless of the law chosen by the parties.

In this scenario, a well-drafted electronic signature clause becomes an essential risk mitigation tool. Consider, for example, a wording such as:

Each Party acknowledges and agrees that such electronic signature satisfies any written form requirement applicable to this Agreement under Italian law (including Articles 1341 and 1342 of the Civil Code and the eIDAS Regulation) and under French law.

This clause operates on two tracks: on one hand, it anticipates and addresses the question of formal validity under each potentially applicable law; on the other, the waiver of the objection of formal invalidity (the so-called waiver clause) aims to prevent a party from raising purely tactical objections regarding the form of the signature. The admissibility of such a waiver, however, has limits: where form is required ad substantiam or to protect mandatory interests, the waiver could be deemed unenforceable.

Practical Drafting Recommendations

Here are the main recommendations for an effective electronic signature clause in international contracts:

1. Identify the relevant jurisdictions and verify the form requirements of each, paying particular attention to mandatory rules.
2. Specify the platform and the level of signature used (simple, advanced, qualified), always preferring the qualified signature.
3. Include an explicit mutual recognition of the validity of the electronic signature, with specific reference to the rules of each jurisdiction involved.
4. Provide for a waiver clause, being aware of its limits in systems that protect form as a mandatory requirement.
5. Address electronic counterparts, clarifying that each electronically signed copy constitutes an original.
6. Retain evidence: electronic contracting requires documenting not only the signature but the entire signing process.

Conclusion

The electronic signature in international contracts is no longer a novelty, but remains an area where legal caution is essential. The multi-jurisdictional regulatory mosaic, the pitfalls of overriding mandatory rules, and the peculiarities of legal systems such as Italy’s – consider the double signature required for unfair contract terms – call for a mindful approach to drafting.

A well-drafted electronic signature clause is not a mere formality: it is an insurance policy against legal uncertainty.

In a forthcoming article, we will explore the impact of artificial intelligence on the management of international contracts and the new challenges posed by the European AI Act.