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Arbitration agreements


What are the validity requirements for an arbitration agreement?

Article 9.1 of the Arbitration Act states that an arbitration agreement may be a clause in a contract or a separate agreement. In both cases the agreement must express the willingness of the parties to submit to arbitration all or certain disputes arising between them in respect of a specific legal relationship, whether contractual or non-contractual.

According to Article 9.3 of the act, to be valid, an arbitration agreement should be:

  • executed in writing; and
  • contained in a document signed by the parties or in an exchange of letters, telegrams, telexes, faxes or any other means of communication which ensures that a record of the agreement is kept.

This requirement is fulfilled if the arbitration agreement is readily available and accessible for subsequent consultation.

Under Article 9.2 of the act, if an arbitration agreement is included in a standard contract, its validity and interpretation will be governed by the rules applicable to the contract.

With regard to international arbitration, Article 9.6 of the act specifically states that, to be valid, an arbitration agreement must meet the requirements set out in:

  • the rules of law chosen by the parties to govern the agreement;
  • the applicable substantive law; or
  • Spanish law.

Enforcement of agreements

How are arbitration agreements enforced in your jurisdiction? What is the attitude of the national courts towards arbitration agreements?

The Spanish courts enforce arbitration agreements and adopt a pro-arbitration stance. Section 11.1 of the Arbitration Act prevents ordinary courts from settling any dispute submitted to arbitration if one of the parties to the agreement has initiated the corresponding arbitration process.


Can an arbitral tribunal with its seat in your jurisdiction consolidate separate arbitral proceedings under one or more contracts, and, if so, in what circumstances?

While the Arbitration Act contains no specific provisions regarding the joinder of other actions, the rules of many institutions permit this. Customarily, the prerequisite is a link between all actions initiated during arbitration.

In addition, Spanish law does not afford arbitral tribunals the power to assume jurisdiction over individuals or entities which are not party to the arbitration agreement. However, according to some case law, arbitration agreements may bind non-signatories if they have a close and strong relationship with one of the signatories or have played a relevant role in the performance of the relevant contract ( so-called ‘tacit acceptance of the arbitration agreement’). This issue is analysed on a case-by-case basis, as Spain has no specific case law on the subject (a July 9 2007 Supreme Court decision was against the extension of arbitration clauses to non-signatories, while a May 26 2005 decision favoured such extension).

Choice of law

How is the substantive law of the dispute determined? Where the substantive law is unclear, how will a tribunal determine what it should be?

Pursuant to Article 34 of the Arbitration Act, arbitral tribunals must decide disputes in accordance with the law or rules chosen by the parties. Any designation of law or a legal system is deemed to refer directly to the substantive laws of that respective state. In the absence of a relevant agreement between the parties, the arbitral tribunal may directly – without resorting to conflict of law rules – apply the law that it considers most appropriate. The arbitrators may make such determinations ex aequo et bono (ie, according to what is right and good) only if expressly authorised by the parties.

Regardless of the substantive law chosen by the parties, if the seat of arbitration is in Spain, mandatory laws affecting Spanish public order may not be infringed. Otherwise, any award may subsequently be declared null and void.


Are there any provisions on the separability of arbitration agreements?

In accordance with Article 22 of the Arbitration Act, arbitration agreements are considered independent from the contract in which they are included and arbitrators can adjudicate on their own jurisdiction. Thus, the principle of competence-competence is expressly recognised in Spain.

Further, arbitrators’ decisions on their jurisdiction may be challenged only by means of an application to set aside the final award or a separate award on jurisdiction.

Multiparty agreements

Are multiparty agreements recognised?

The Arbitration Act does not address multiparty agreements. However, they are admitted by reference in Article 15.2 and case law, provided that all prerequisites in Article 9 are met.

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