Publication date: April 14, 2026
Concluding international trade agreements is becoming increasingly easier and risk-free. International trade underpins the global economy more than ever before, due to globalization and the increasing unification of legal provisions governing this matter, along with the expansion of international agreements and intergovernmental cooperation. However, international law does not always address the needs of complex relationships between entities from different countries, which leads to a lack of certainty and predictability in legal transactions. To stabilize international contractual relations, efforts are being made to standardize private law at the international level and adapt state regulations to the needs of cross-border trade. This task is becoming increasingly easier due to the rapid development of new technologies and the digitization of organizational centers. Organizations such as the Hague Conference on Private International Law are engaged in the unification of private law.
1. INTERNATIONAL ORGANIZATIONS WORKING FOR THE DEVELOPMENT OF INTERNATIONAL PRIVATE LAW
The Hague Conference on Private International Law (HCCH) is an international organization based in The Hague. The HCCH’s goal is to unify the rules of private international law and adapt it to a dynamically changing reality. The organization’s activities are characterized by flexibility and timelessness, ensuring that solutions adopted in earlier years remain relevant and relevant, even within the framework of domestic regulations. The organization has 92 members, 91 states (including Poland) and the European Union, which joined as a separate entity on March 3, 2007. This innovative, multi-level approach to integration improves cooperation in international law. The organization strives for integration not only in Europe and North America but also in other parts of the world. The opening of the Regional Office for Asia and the Pacific (HKPPM ) in Hong Kong in 2012 opened up opportunities for cooperation among local countries, allowing the organization to expand its global reach. There is a lively debate on the adequacy of various instruments for the unification of international private law, their form, rank, and scope.
HCCH collaborates with UNCITRAL (United Nations Commission on International Trade Law) and UNIDROIT (The International Institute for the Unification of Private Law). They are called the “three sisters of private international law” because they collaborate dynamically to promote and unify private law worldwide. UNCITRAL, the UN Commission on International Trade Law, is the main axis of harmonization and unification in this field, and its members come from various geographic regions, representing different approaches to economics and legislation. UNIDROIT is an international governmental organization striving to unify private law, particularly customary law, in international trade. The Ministry of Development and Technology of the Republic of Poland is responsible for coordinating cooperation and liaising with these organizations. All three conduct organized activities for the development of private international law in various forms. They publish guides informing about the solutions they have jointly developed, as the instruments issued by these three entities are interoperable and complementary. Organizations promote their uniform interpretation and complementary application.
2. RULES REGARDING THE CHOICE OF LAW APPLICABLE TO INTERNATIONAL TRADE AGREEMENTS
On March 19, 2015, the HCCH approved the Principles on the Choice of Law in International Trade Agreements. This is a soft -law act, the first of its kind issued by this organization – it is not a normative act and is not binding on the organization’s members. These are recommendations that can be used by national and EU legislators in the legislative process regarding the possibility of choosing applicable law. The recommendations can serve as a model for national, regional, supranational, and international instruments. The organization strives to make regulations in this area binding, but currently focuses on creating conditions and suggesting to member states that they gradually amend their own laws. Arbitration courts may be guided by the recommendations, particularly if domestic law does not provide appropriate solutions for a specific type of situation, yet provides for the institution of choice of applicable law. Arbitration institutions in countries such as Thailand and Indonesia already refer to the HCCH principles in their work, strengthening the ability of parties to international trade agreements to choose applicable law. In Paraguay and Uruguay, these principles have influenced official legislative work on reforming international contract law. From 2015 to 2021, 16 institutions from four continents have incorporated the principles into their internal regulations or promoted them in other ways. This supports the principles of freedom of contract and party autonomy. The Permanent Bureau, the main body of the HCCH, which serves as a multinational secretariat, has invited nine organizations involved in the harmonization of international private law to collaborate with them to promote their principles and support these entities. The HCCH recommendations reflect global trends.
2.1. DOCUMENT CONTENT
The Act applies to situations in which the parties enter into an international contract, where each party is engaged in commercial or professional activity and wishes to conclude the contract under foreign law, other than the automatic provisions of general law. The chosen law governs all matters relating to the contract, in particular its interpretation, the rights and obligations arising therefrom, its validity and the consequences of invalidity (the document contains a non-exhaustive list of these elements). It does not apply to consumer or employment contracts, which protects consumers and employees due to the disparity in the parties’ positions. An international contract is defined there as a contract whose parties do not have their registered offices in the same country and all their relations are not connected with that single country. The Act includes a list of exclusions for matters such as the capacity of natural persons, bankruptcy, partnerships, other collective organizations, and trusts. This means that in the context of M&A, the rules do not apply to agreements concerning the internal organization of a company, for example, those establishing the rights and obligations of shareholders or management. However, in contracts beyond this scope, between a company and third parties, the law chosen by the parties need not be in any way related to them or the relationship between them; the choice may apply to the entire contract or only part of it. The choice of law must be made expressly or clearly indicated by the provisions of the contract and the circumstances to minimize the need for interpretation. Therefore, the choice of law applicable to the main contract does not automatically apply to ancillary contracts, such as a surety agreement, and when making a surety agreement, the choice must also be clearly stated if it is intended. A choice of law clause does not require a specific form to be valid; the choice can be made or changed at any time, and this does not affect the validity of the contract in terms of form. The validity of the choice of foreign law is assessed based on the chosen law. The invalidity of the contract cannot be the sole basis for challenging the choice of applicable law. A court may disapply a provision of foreign law when it clearly contradicts fundamental principles of public policy in the country where it adjudicates. These principles aim to unify the law, which will result in greater predictability and, therefore, legal certainty. International trade is impossible without this stability, as legal relationships extending beyond national borders are characterized by less predictability and increased risk. Therefore, an appropriate regulatory framework is needed, within which entities can operate with confidence and freedom, while at the same time being subject to reasonable constraints.
2.2. CHOICE OF APPLICABLE LAW AND CHOICE OF FORUM
Choosing the jurisdiction of a specific court is not the same as choosing the applicable law; this is a separate issue, regulated by the Hague Convention of 30 June 2005 on Choice of Court Agreements. Generally, choosing a court does not prejudge the choice of applicable law, but by designating a court located outside Poland, we also agree to it applying the procedural law in force in the country where it adjudicates. The choice of law applicable to the contract determines the choice of substantive law that will govern the very nature of the legal relationship. Therefore, when including the above clauses in the contract, the choice must be made precisely, clearly, and unambiguously to avoid any room for interpretation, as these are two separate issues. If we only seek to exclude the jurisdiction of Polish courts, while maintaining the Polish legal system as the basis for our relationship, we must make this clear. The German Federal Court of Justice, in its judgment of 16 September 2015 (VIII ZR 17/15), interpreted the factual circumstances in this type of case and found that the parties, by choosing the competent court, also implicitly chose the law applicable to the contract.
The leading international regulations on the choice of applicable law are the EU regulations: the Regulation of 17 June 2008 on the law applicable to contractual obligations, known as Rome I, and the Regulation of 11 July 2007 on the law applicable to non-contractual obligations, known as Rome II. The territorial scope of these regulations is crucial – these are European Union normative acts, applicable only in relations between its Member States, unlike the global scope of the rules developed by the HCCH. However, these are binding acts, directly implemented into the internal legal systems of EU countries, so their effectiveness is greater. The most relevant regulation on this topic is the first one, concerning contractual obligations – Rome I. The choice of law under this regulation primarily concerns the interpretation of the contract and the consequences of non-performance. The act also provides conflict-of-law rules applicable in the event of the parties’ failure to choose the applicable law – these rules are specifically defined for contracts for the sale of goods, contracts for the provision of services, contracts concerning real estate rights or the right to use real estate, franchise agreements, and distribution agreements. The regulation also defines its scope of application, which is similar to that defined in the HCCH principles; for example, matters relating to company law, arbitration agreements, and agreements on the selection of court are excluded. The regulation also governs the choice of applicable law in consumer and employment contracts, unlike the Hague principles. As in these cases, the freedom to choose foreign law is also provided for, but this choice must be express and unambiguous. Similar restrictions apply as in the HCCH document, as a purely domestic contract cannot be concluded with the choice of foreign law as the applicable law. The choice of law can occur before or after the conclusion of the contract, and for all or part of it. The regulation clearly drew considerable inspiration from the principles issued by the HCCH, yet they are significantly more general and universal. The instruments drafted by this organization are characterized by flexibility, allowing for their application in countries outside the European legal culture.
In the context of commercial relations with entities outside the European Union, the above-mentioned regulations do not apply, as they apply only to relations between Member States. In such cases, bilateral agreements between Poland and the country where the counterparty has its permanent residence or registered office should be consulted. If no agreement exists regulating this matter, Polish regulations should be relied upon.
The core of Polish regulations enabling the choice of law applicable to international contracts is Article 353 § 1 of the Civil Code, which provides for freedom of contract. This is a fundamental principle of contract law, allowing for the free shaping of civil law relationships – taking into account the nature of the concluded relationship, the principles of social coexistence, and applicable law. Article 1105 of the Civil Procedure Code, on the other hand, allows for the choice of court jurisdiction, which is a separate issue. It is not possible to change the court jurisdiction for cases falling within the exclusive jurisdiction of Polish courts, in the field of labor law, concluded by a Polish consumer (unless it concerns the consumer themselves), or arising from an insurance relationship. A provision changing the court jurisdiction only for a claim brought by one party (other than the consumer) is ineffective.
The possibility of choosing the applicable law is established in the Private International Law Act. Article 4 regulates this issue in a manner very similar to the EU regulation and the principles developed by the HCCH, but in a much narrower scope. The choice of law should be clear and unambiguous and can be made after the legal relationship has been established. The legal capacity of a party to a contract is governed by its national law; in the case of a legal person, it is governed by the law of the country in which it is headquartered. The form and the very fact of performing or not performing a legal act are assessed in light of the applicable law chosen in the contract or by operation of law. Therefore, Polish law explicitly provides for the possibility of choosing a law other than the law itself governing the contract. For this reason, the application of the Hague principles is possible in situations not expressly provided for in Polish law. The principles can serve as a guide and interpretative rules, expanding the application of the law established by Article 4 of the Private International Law Act. Together with EU regulations, these provisions create a comprehensive instrument enabling the shaping of legal relations in terms of the choice of applicable law in a well-thought-out and safe manner, eliminating legal uncertainty and smoothing the flow of international trade.