International Arbitration

In Switzerland, arbitration is governed by two statutory regimes:

• Chapter 12 of the Private International Law Act (PILA), Articles 177–194, for international arbitration; and
• Part 3 of the Civil Procedure Code (CPC), Articles 353–399, for domestic arbitration.

Swiss law does not impose strict formal requirements on arbitration agreements. While the agreement must be set out in writing, there is no need for a formally signed document. Arbitration clauses may also be valid if concluded by other forms of communication, such as email or fax, as long as the parties’ intent to arbitrate can clearly be established (see question 3.1).

Yes, Swiss law differentiates between domestic and international arbitration, with the key differences being:

• the location of the parties; and
• the applicable legal framework.

International arbitration is governed by Chapter 12 of the PILA. An arbitration is considered international if, at the time the arbitration agreement was concluded, at least one of the parties had its domicile or place of business outside Switzerland (Article 176(1) of the PILA).

Domestic arbitration, on the other hand, is governed by Part 3 of the CPC. It applies when all parties had their domicile or place of business in Switzerland at the time the arbitration agreement was entered into.

Article 176(2) of the PILA provides that parties in an international arbitration may agree to subject their arbitration to the provisions on domestic arbitration in the CPC instead. Likewise, Article 353(2) of the CPC allows the parties to opt into Chapter 12 of the PILA, even if the arbitration would otherwise be considered domestic.

Switzerland’s arbitration legislation is not based on the UNCITRAL Model Law. However, Chapter 12 of the PILA shares several core principles with the UNCITRAL Model Law, such as:

• party autonomy;
• the principle of separability of the arbitration agreement; and
• minimal court intervention.

No, not all provisions of Swiss arbitration law are mandatory. Both the CPC and the PILA are largely based on the principle of party autonomy. This means that parties are free to agree on many procedural aspects of the arbitration, including:

• the constitution of the tribunal;
• the seat; and
• the procedural rules.

However, a limited number of provisions in Chapter 12 of the PILA and Part 3 of the CPC are mandatory and apply regardless of the parties’ agreement. These include the following:

• Article 177(1) of the PILA and Article 354 of the CPC on arbitrability: Only disputes involving an economic interest can be submitted to arbitration.
• Article 178(1) of the PILA and Article 358 of the CPC on the form of the arbitration agreement: The arbitration agreement must be:
• • in writing; or
  • in a form allowing for written proof (eg, email).
• This form requirement is mandatory.
• Article 180(1)(c) of the PILA and Article 367 of the CPC on the independence and impartiality of arbitrators: A party may challenge an arbitrator if there are justifiable doubts as to their impartiality or independence.
• Article 182(3) of the PILA and Article 373(4) of the CPC on due process: The arbitral procedure must guarantee:
• • equal treatment of the parties; and
  • their right to be heard.
• Article 185 of the PILA and Articles 356 and 374 of the CPC on assistance from the state courts: The courts have certain non-waivable powers (eg, ordering interim measures or assisting with evidence) which the parties cannot fully exclude.

In mid‑2020, the Swiss Parliament adopted a revision to Chapter 12 of the PILA, which entered into force on 1 January 2021.

The key changes included express provisions on:

• the correction, interpretation and supplementation of arbitral awards (Article 189a of the PILA);
• the option to file certain submissions to the Federal Supreme Court in English (Article 77(2bis) of the Federal Supreme Court Act); and
• an updated, technology-neutral formulation of the form requirement for arbitration agreements (Article 178(1) of the PILA).

In March 2023, the Swiss Parliament adopted a revision to the CPC, which entered into force on 1 January 2025. While Part 3 of the CPC on arbitration itself remains unchanged, several amendments – such as the option to conduct certain court proceedings in English with party consent (Article 129(2)(b) of the CPC) and the option to use electronic means for hearings and evidence-taking (Articles 141a, 141b, 170a of the CPC) – can indirectly benefit arbitration-related court steps by:

• reducing translation needs; and
• enabling remote participation.

At this time, there are no major reforms planned to Chapter 12 of the PILA or Part 3 of the CPC.

Yes, Switzerland is a signatory to the 1958 New York Convention on the Recognition and Enforcement of Foreign Arbitral Awards. It ratified the convention in 1965.

At the time of ratification, Switzerland entered a reciprocity reservation pursuant to Article I (3), limiting the enforcement of awards to those rendered in other contracting states. This reservation was formally withdrawn in 1993 and since then, Switzerland has applied the convention without reservation. The recognition and enforcement of foreign arbitral awards are governed by Article 194 of the PILA, which incorporates the convention into Swiss law. Thus, Swiss courts generally adopt a pro-enforcement stance, consistent with the convention’s objectives.

Yes. In addition to the New York Convention, Switzerland is a signatory to several other treaties relevant to arbitration.

In 1968, it approved the 1965 Convention on the Settlement of Investment Disputes between States and Nationals of Other States, allowing legal disputes between foreign investors and governments to be resolved with the World Bank’s support and supervision.

Switzerland is also a contracting party to the Energy Charter Treaty (1994), which provides a legal framework for investment arbitration in the energy sector.

In addition, while the Geneva Protocol of 1923 and Geneva Convention of 1927 are largely obsolete due to the New York Convention, Switzerland remains formally bound by them.

Switzerland has also concluded over 120 bilateral investment treaties, most of which include provisions for international arbitration between investors and states. A full list of treaties to which Switzerland is a party can be accessed via the website of the Federal Department of Foreign Affairs (www.eda.admin.ch/eda/en/fdfa/foreign-policy/international-law/internationale-vertraege.html)

International arbitration: Article 177(1) of the Private International Law Act (PILA) stipulates that a dispute is arbitrable if it involves a claim of an economic nature, regardless of whether the parties are private or public entities. The term ‘economic interest’ is interpreted liberally by the Federal Supreme Court. It includes claims that are objectively capable of monetary valuation, such as:

• commercial, contractual or tort claims; and
• even certain corporate or competition law disputes.

However, matters involving status – such as divorce, nationality or certain public law issues – are generally considered non-arbitrable.

Domestic arbitration: For domestic arbitration, Article 354 CCP uses a similar standard, allowing arbitration for disputes over rights that the parties may freely dispose of. In other words, the matter must be capable of resolution through an out-of-court settlement or by admission of a claim in ordinary civil proceedings. As a result, certain types of disputes – such as those arising under employment law or family law – are generally excluded from domestic arbitration, even though they may be of an economic nature and thus arbitrable under the rules governing international arbitration in Switzerland.

No, Swiss law does not impose substantive restrictions on the choice of seat. Under both Chapter 12 of the PILA and Part 3 of the Civil Procedure Code (CPC), the parties are free to choose any seat of arbitration, including one outside of Switzerland, regardless of the parties’ nationality or domicile.

However, the legal framework that governs the arbitration depends on the seat:

• If the seat is in Switzerland and the arbitration is international in nature, Chapter 12 of the PILA applies.
• If the seat is in Switzerland and the arbitration is domestic, Part 3 of the CPC (Articles 353–399) applies.
• If the seat is outside Switzerland, Swiss arbitration law does not apply, unless Swiss procedural rules are chosen voluntarily.

International arbitration: Under Article 178(1) of the Private International Law Act (PILA), an arbitration agreement must be in writing or in a form that allows it to be evidenced by text (email or other electronic communications). No signature or formal document is required as long as the arbitration agreement clearly expresses the parties’ intent to submit their legal relationship to arbitration (see question 1.1). Substantively, under Article 178(2) of the PILA, the arbitration agreement is valid if it satisfies the requirements of:

• the law chosen by the parties;
• the law applicable to the dispute; or
• Swiss law.

This ‘favor validitatis’ rule ensures maximum enforceability by accepting the most favourable of the three laws.

Domestic arbitration: The same formal and substantive requirements apply to domestic arbitration under Articles 357 and 358 of the Civil Procedure Code (CPC).

Yes. Article 178(3) of the PILA and Article 357(2) of the CPC expressly recognise the principle of separability. They provide that the arbitration agreement is valid even if the main contract is:

• invalid;
• non-existent; or
• terminated.

This ensures that the tribunal retains jurisdiction to determine disputes, including those concerning the validity of the underlying contract.

Swiss case law and doctrine consistently uphold this principle, affirming that the arbitration clause is treated as autonomous from the main contract for jurisdictional purposes.

Yes. Under Article 182(1) of the PILA, if the parties have not agreed on the arbitral procedure, the tribunal has the power to determine the procedure, either directly or by reference to institutional rules. This includes the authority to determine the seat of the arbitration and the language in which proceedings will be conducted. However, in doing so, the tribunal must ensure compliance with Article 182(3) of the PILA, which guarantees:

• equal treatment of the parties; and
• their right to be heard.

In domestic arbitration, if the seat has not been designated by the parties, the tribunal must determine it under Article 355(1) of the CPC. If the tribunal is unable to do so, the competent state court with jurisdiction in the absence of an arbitration agreement will decide the seat pursuant to Article 355(2) of the CPC.

Where the Swiss Rules of Arbitration of June 2021 apply, they operate as party-chosen procedural rules alongside Chapter 12 of the PILA. If the parties have not fixed the seat (or it is unclear), Article 17(1) of the Swiss Rules provides that the Swiss Arbitration Centre Court:

• will determine the seat, taking into account all relevant circumstances; or
• may request the tribunal to do so.

If there is no party agreement, the tribunal also may determine the language(s) under Article 18 of the Swiss Rules.

According to Article 186(2) of the Private International Law Act (PILA) and Article 359(2) of the Civil Procedure Code (CPC), a party must raise any objection to the tribunal’s jurisdiction no later than the submission of the first pleading on the merits. If the party fails to do so, the objection is deemed waived.

The objection must be raised explicitly – typically in the statement of defence or any equivalent first pleading – clearly stating the grounds for lack of jurisdiction. If the objection is not timely or properly raised, the party is considered to have accepted the tribunal’s jurisdiction.

If the Swiss Rules of Arbitration of June 2021 apply, jurisdictional objections must be raised before any defence on the merits (Article 23(3) of the Swiss Rules). If such an objection is raised, the statement of defence must set out its factual and legal basis (Article 21(2) of the Swiss Rules). This mirrors Article 186(2) of the PILA, which also requires a plea of lack of jurisdiction to be raised prior to any pleading on the merits.

Yes. Under Article 186(1) of the PILA, the tribunal has the express authority to rule on its own jurisdiction. This reflects the internationally recognised principle of competence-competence. The tribunal may decide jurisdictional questions either as a preliminary issue or together with the merits, depending on the circumstances of the case.

The same principle applies to domestic arbitration and is stipulated in Article 359(1) of the CPC.

If the Swiss Rules of Arbitration of June 2021 apply, the competence-competence principle is set out in Article 23(1), which empowers the tribunal to rule on its own jurisdiction, including the existence, validity or scope of the arbitration agreement.

Yes, but only in limited circumstances. Under Swiss law, once a tribunal is constituted, it has priority to rule on its own jurisdiction based on the principle of competence-competence (see question 4.2). Swiss courts will generally not intervene pre-emptively.

However, if the tribunal issues a preliminary award on jurisdiction, the losing party may immediately challenge that decision before the Federal Supreme Court under Article 190(3) of the PILA or Article 393(b) of the CPC. This is the only scenario where a party can seek a state court ruling on jurisdiction before the final award.

If the tribunal rules on jurisdiction in the final award, the affected party may still challenge that award on jurisdictional grounds under Article 190(2)(b) of the PILA or Article 393(b) of the CPC.

Under Swiss law, there are no specific restrictions on who can be a party to an arbitration agreement. Any natural or legal person – including states and state entities – may enter into such an agreement, provided that they have the legal capacity to do so under the applicable law. The question of legal capacity is determined not by the lex arbitri, but by the general conflict-of-laws rules in the Private International Law Act (PILA).

For natural persons, Articles 35 and 36 of the PILA designate the law of the person’s domicile as governing their legal capacity. For legal entities, Articles 154 and 155 of the PILA refer to the law of the state of incorporation.

Where Swiss law governs, the capacity to be a party depends on the ability to exercise civil rights, as set out in Articles 12 to 19 of the Swiss Civil Code. Individuals must be of full age and legally competent; while entities must fulfil the formal criteria set out in their governing law.

Additionally, in international arbitration, Article 177(2) of the PILA explicitly provides that states and state-controlled entities cannot invoke their own laws to avoid being bound by an arbitration agreement.

Yes. Although neither the PILA nor the Civil Procedure Code (CPC) sets out an exhaustive list of party duties, several obligations arise from:

• general principles of law;
• arbitral practice; and
• institutional rules.

Under Article 182(3) of the PILA, the tribunal must ensure equal treatment and the right to be heard. This provision implies a duty on the parties to conduct themselves in a manner that does not obstruct these procedural guarantees. More broadly, parties are bound by the duty to act in good faith, as recognised under Article 2 of the Civil Code.

Where the Swiss Rules of Arbitration of June 2021 apply, additional obligations include:

• the duty to pay advances on costs (Article 41 and Appendix B);
• the obligation to comply with procedural calendars and limits on submissions (Article 19); and
• the obligation to comply without delay with tribunal orders and the final award (Article 16(1) and Article 34(2)).

International arbitration: Chapter 12 of the PILA remains silent on issues such as:

• joinder;
• intervention; or
• consolidation.

Nevertheless, multi-party proceedings are fully permissible and such matters are typically governed by:

• the arbitration agreement;
• the chosen institutional rules; and
• the discretion of the tribunal pursuant to Article 182(1) of the PILA.

The tribunal must always ensure that the requirements of equal treatment and the right to be heard under Article 182(3) of the PILA are respected, particularly where additional parties are involved.

Domestic arbitration: By contrast, the CPC expressly addresses multi-party constellations. Article 376(1) of the CPC allows multiple claimants or respondents to participate in a single proceeding where:

• the parties are bound by one or more compatible arbitration agreements; and
• the claims are either factually connected or legally similar.

The CPC also provides for the possibility of third-party intervention or joinder during the arbitration, provided that:

• the third party is bound by the same arbitration agreement; and
• the tribunal agrees to its participation.

Swiss Rules of Arbitration: In proceedings conducted under the Swiss Rules of Arbitration of June 2021:

• joinder and related participation are governed by Article 6 (decided by the tribunal after constitution); and
• consolidation is decided by the Swiss Arbitration Centre Court under Article 7.

International arbitration: In international arbitration, the law applicable to the arbitration agreement is determined according to Article 178(2) of the Private International Law Act (PILA). The arbitration agreement is deemed valid if it complies with the requirements of:

• the law chosen by the parties;
• the law governing the main contract; or
• Swiss law (see question 3.1).

Domestic arbitration: The Civil Procedure Code (CPC) does not contain a specific conflict-of-laws rule for the law governing the arbitration agreement. In practice, where the parties have not expressly chosen the law applicable to the arbitration clause, Swiss law will usually apply by default.

However, the tribunal may apply a different law if:

• the parties have made a valid choice; or
• the contract itself is clearly governed by a foreign law and there’s no contrary indication.

Yes, under Article 187(1) of the PILA, the tribunal must decide on the dispute according to the law chosen by the parties as the substantive law governing the merits. This choice is generally upheld, whether it is made expressly or can be clearly inferred from the contract or surrounding circumstances. Swiss law does not require that the chosen law be connected to the dispute or the parties.

If the parties have not designated a governing law, Article 187(1) of the PILA authorises the tribunal to apply the law with which the case has the closest connection. However, in doing so, it must apply conflict-of-laws reasoning to identify the most appropriate substantive law.

Similarly, in domestic arbitration, Article 381(1)(a) of the CPC requires the tribunal to apply the legal rules chosen by the parties. If the parties have not made a choice, Article 381(2) mandates that the law that a Swiss state court would apply should be applied to the matter, following Swiss private international law rules.

In both regimes, Article 187(2) of the PILA and Article 381(1)(b) of the CPC allow the parties to authorise the tribunal to decide the dispute ex aequo et bono or as amiable compositeur, but only if such authority is expressly granted.

Here again, Article 35 of the Swiss Rules of Arbitration of June 2021 mirrors the PILA. In the absence of a choice, the tribunal applies the law with the closest connection. Article 35(2) allows for ex aequo et bono decisions only with express party consent.

Yes. Although under Chapter 12 of the Private International Law Act (PILA) there is no specific statutory provision addressing consolidation, it is generally accepted that consolidation is permitted where the parties have agreed to it, either expressly or through incorporation of institutional rules that allow for consolidation.

For example, Article 7 of the Swiss Rules of Arbitration of June 2021 allows for consolidation in certain circumstances, including where:

• the parties consent;
• the disputes involve the same parties and legal relationship; or
• compatible arbitration agreements are involved.

The tribunal must consult the parties and consider all relevant procedural circumstances before making such a decision.

In contrast, Article 376(2) of the Civil Procedure Code (CPC), which applies to domestic arbitration, explicitly provides for the possibility of joining claims between the same parties within a single proceeding. This is allowed where the claims are:

• factually connected; and
• governed by compatible arbitration agreements.

Chapter 12 of the PILA does not contain explicit provisions on the joinder of additional parties to ongoing arbitration proceedings. Nevertheless, such joinder is generally permitted under Swiss arbitration law if it is consistent with:

• the principle of party autonomy; and
• the right to be heard.

Leading institutions – such as the International Chamber of Commerce, the Swiss Arbitration Centre and the German Arbitration Institute – all provide mechanisms for consolidation, typically under conditions such as:

• the same parties being involved,
• compatible arbitration agreements, or
• closely connected legal or factual issues.

Specifically, Article 6 of the Swiss Rules of Arbitration of June 2021 provides that before tribunal constitution, a joinder can occur through a combined notice of arbitration. Thereafter, it requires the consent of all parties and the approval of the tribunal, considering jurisdiction and due process.

In contrast, the CPC expressly contains a provision on the joinder of additional parties. According to Article 376(3), the joinder or intervention of an additional party is allowed:

• if an identical arbitration agreement exists between the third party and the original parties; and
• subject to the consent of the tribunal.

According to consistent case law of the Federal Supreme Court, the arbitration agreement follows the claim and is transferred with it, unless otherwise agreed. This applies even if the assignee was not a signatory to the arbitration agreement, as long as it assumes rights (and obligations, where applicable) arising from a contract containing such a clause.

As for other third parties, such as shareholders or subcontractors, they are not automatically bound by an arbitration agreement unless they:

• have expressly consented to it; or
• can be shown to have implicitly accepted it based on:
• • their conduct;
  • their legal relationship; or
  • the structure of the transaction.

In this context, Article 697n of the Civil Code, in force since 1 January 2023, allows Swiss companies limited by shares to include arbitration clauses in their articles of corporation, providing for disputes to be resolved by arbitration seated in Switzerland. Due to the references in Article 764(2) and the new Article 797a of the Civil Code (which entered into effect on 1 January 2023), these principles also apply to:

• Swiss partnerships limited by shares; and
• Swiss limited liability companies.

International arbitration: Article 179(1) of the Private International Law Act (PILA) provides that the parties are free to agree on the appointment procedure. This agreement may be contained directly in the arbitration clause or through incorporation of institutional arbitration rules, such as:

• the Swiss Rules of Arbitration of June 2021; or
• the International Chamber of Commerce Arbitration Rules.

If the parties have not agreed on a procedure, the default mechanism applies – in a three-member tribunal:

• each party appoints one arbitrator; and
• the two party-appointed arbitrators appoint the chair.

If a party fails to appoint its arbitrator, or if the arbitrators cannot agree on the chair, the competent state court at the seat of arbitration will make the necessary appointment upon request.

Domestic arbitration: In domestic arbitration, the rules for appointing the tribunal are set out in Articles 360 to 371 of the Civil Procedure Code (CPC). Similar to international arbitration, the parties are free to determine the appointment process. In the absence of such agreement, the procedure mirrors that of the international regime.

Swiss Rules of Arbitration: Where the Swiss Rules apply, Articles 8–11 govern the appointment of arbitrators. For a sole arbitrator, the parties are to jointly nominate; failing that, the court appoints. For a three-member tribunal, each party nominates one co-arbitrator and the two co-arbitrators nominate the presiding arbitrator; if a party fails to nominate, or the co-arbitrators cannot agree on the presiding arbitrator, the court makes the necessary appointment (Articles 10-11).

No. Swiss law does not impose strict requirements as to the number or qualifications of arbitrators. It provides a flexible framework.

In both international arbitration and domestic arbitration, the parties are free to determine the number of arbitrators. If the parties do not specify this, the default rule is a panel of three arbitrators according to Article 179(1) and Article 360(1) of the CPC. The law does not prescribe specific qualifications, but arbitrators must be independent and impartial. In the context of independence, however, the parties have a ‘duty of curiosity’, which requires them to take reasonable steps to ensure that the tribunal offers sufficient guarantees of independence.

Where the Swiss Rules of Arbitration of June 2021 apply and the parties have not agreed on the number of arbitrators, the Swiss Arbitration Centre Court will determine whether the case will be heard by one or three arbitrators (Article 8), taking into account the circumstances.

Article 180(1) of the PILA provides that an arbitrator may be challenged if:

• there are justifiable doubts as to their independence or impartiality;
• they do not meet the qualifications agreed by the parties; or
• there is valid grounds for removal under the agreed procedure.

However, a party may not challenge an arbitrator it has appointed unless the grounds for challenge became known only after the appointment.

In domestic arbitration, Article 367 of the CPC provides for similar grounds – an arbitrator may be challenged for:

• lack of independence or impartiality; or
• failure to meet party-agreed qualifications.

In both regimes, the challenge must be raised without undue delay once the relevant facts are known; otherwise, the right to challenge is forfeited. Article 180a of the PILA and Article 369 of the CPC allow the submission of a written challenge within 30 days of the challenging party becoming aware of the grounds for challenge.

Under Article 179(1) of the PILA, the parties may agree on a procedure to replace an arbitrator. If they do not, the replacement follows the original appointment method. Should that fail, Article 179(2) of the PILA allows the state court at the seat of arbitration to appoint a replacement. If no seat is agreed, the first court seized has jurisdiction. The court must appoint unless a summary review under Article 179(3) of the PILA reveals that no arbitration agreement exists. Article 179(4) of the PILA permits the court to step in if a party or arbitrator fails to act within 30 days. In multi-party cases, Article 179(5) of the PILA allows the state court to appoint all arbitrators.

In domestic arbitration, Article 370 of the CPC allows the parties to agree on a replacement procedure. If they fail to do so, the court at the seat of arbitration may appoint a new arbitrator under Article 368, generally following the method set out in Article 360.

In both regimes, the tribunal is reconstituted and the proceedings continue.

Similarly, under Article 15 of the Swiss Rules of Arbitration of June 2021, a replacement is made using the same procedure as the original appointment (Articles 10–11). The reconstituted tribunal may continue the arbitration without repeating prior steps, unless required for fairness.

Arbitrators are subject to several core duties under Swiss law. Some of these are expressly set out in legislation, while others derive from:

• general legal principles;
• case law; and
• institutional rules.

In both the international and the domestic regimes, arbitrators must:

• be independent and impartial; and
• disclose any circumstances that could give rise to justifiable doubts in this regard.

This duty is explicitly stated in:

• Article 367 of the CPC for domestic cases; and
• Article 180(1)(c) of the PILA for international arbitration.

Arbitrators also have a duty to conduct the proceedings fairly and efficiently, respecting the principles of equal treatment and the right to be heard (Article 182(3) of the PILA and Article 373(1) of the CPC).

In addition, some arbitrator duties arise from specific institutional rules. The Swiss Rules of Arbitration of June 2021, for example, require:

• arbitrators to be and remain impartial and independent, with a continuing duty of disclosure (Article 12);
• the tribunal to organise and conduct the proceedings to ensure equal treatment and the right to be heard, while adopting measures to ensure efficiency (Article 19(1)); and
• all participants to act in good faith and contribute to efficient conduct (Article 16(1)).

(a) Procedure, including evidence?

International arbitration: Under Article 182(1) of the PILA, the parties are free to agree on the procedure. If they do not, the tribunal may conduct the arbitration in the manner it considers appropriate, provided that it respects the mandatory principles of equal treatment and the right to be heard (Article 182(3) of the PILA).

Thus, the tribunal may:

• determine the format and structure of the proceedings;
• set procedural calendars; and
• regulate the admissibility of evidence.

Arbitrators may also:

• hear witnesses and experts;
• request document production; and
• assess the evidentiary value of submissions in the manner they consider appropriate.

While arbitrators have considerable autonomy, they do not have coercive powers. If a party or third party refuses to comply with an evidentiary order, the tribunal may seek assistance from the competent state court under Article 184(2) of the PILA, which may take the necessary measures of compulsion (see question 8.6(c)).

Domestic arbitration: Similar powers apply in domestic arbitration under the CPC, particularly Articles 373 and 375.

Swiss Rules of Arbitration: When the Swiss Rules of Arbitration of June 2021 apply:

• Articles 19 and 26 give the tribunal broad discretion to determine the procedure and assess evidence; and
• Article 26(2) allows it to order document production.

(b) Interim relief?

International arbitration: In international arbitration, Article 183(1) of the PILA allows the tribunal to issue interim measures upon request of a party, unless the parties have agreed otherwise.

Arbitral tribunals may order any provisional measure they deem necessary to:

• preserve rights;
• prevent irreparable harm; or
• secure enforcement of the award.

This includes measures such as:

• freezing assets;
• preserving evidence; and
• restraining specific conduct.

However, tribunals do not have direct powers to enforce such measures.

If a party fails to comply, the requesting party may apply to the competent state court for enforcement under Article 183(2) of the PILA. This also applies in relation to third parties, as tribunals have no jurisdiction over entities not bound by the arbitration agreement.

Domestic arbitration: In domestic arbitration, Article 374(2) of the CPC provides that arbitrators may also grant interim relief unless the parties have excluded this power. As in international arbitration, enforcement may require court assistance in accordance with Article 374(4) of the CPC.

(c) Parties which do not comply with its orders?

If a party fails to comply with procedural orders, document production requests or interim measures, the tribunal cannot enforce them through means such as criminal sanctions or physical enforcement. However, where a party’s non-compliance undermines the effectiveness of the proceedings, it may use procedural tools such as:

• limiting the presentation of evidence at some point; or
• continuing the proceedings in the absence of the non-compliant party (provided that there is no valid justification for its conduct).

Whether or not a tribunal may impose private sanctions, such as an astreinte, is contentious.

Furthermore, the tribunal may request assistance from the competent Swiss state court to take steps that the tribunal itself cannot undertake, such as ordering enforcement or compelling third-party cooperation (Article 184(2) of the PILA and Article 375 of the CPC).

(d) Issuing partial final awards?

International arbitration: In international arbitration, tribunals are permitted to issue partial awards or partial final awards on specific issues or claims. This is expressly regulated in Article 188 of the PILA.

A partial award:

• has the same legal status as a final award in respect of the issues it resolves; and
• may be challenged before the Federal Supreme Court under Article 190 of the PILA.

Domestic arbitration: The same applies in domestic arbitration under Article 383 of the CPC.

Swiss Rules of Arbitration: The Swiss Rules of Arbitration of June 2021 also expressly allow the tribunal to issue partial awards in accordance with Article 34(1). These have the same binding effect as final awards.

(e) The remedies it can grant in a final award?

In principle, under both the PILA and the CPC, as long as this does not violate Swiss public policy under Article 190(2)(e) of the PILA, the tribunal is free to grant any remedy available under the law governing the substance of the dispute, including:

• specific performance;
• damages;
• declaratory relief; and
• the creation, modification or termination of legal relationships.

However, limitations may arise from:

• the arbitration agreement;
• the substantive law chosen by the parties; or
• the laws of the state(s) in which enforcement is sought.

Generally, the tribunal must remain within the scope of the parties’ claims and respect due process; but it is otherwise not restricted in the types of final remedies it may grant.

(f) Interest?

There are no restrictions in the PILA or CPC regarding the awarding of interest. Arbitral tribunals seated in Switzerland are therefore empowered to award interest, both pre and post-award.

If the dispute is governed by Swiss substantive law, interest is typically awarded in accordance with Articles 73 and 104 of the Civil Code. The default statutory interest rate is 5% per annum, unless:

• the parties have agreed otherwise; or
• the law provides for a different rate (eg, in cases of commercial transactions or default interest).

Tribunals may also determine the starting date, rate and type of interest (simple or compound), based on party agreement or the governing law. As with other remedies, an award of interest must not violate Swiss public policy if enforcement is sought in Switzerland.

This question is particularly relevant in the context of recent geopolitical developments in Europe, such as:

• sanctions;
• cross-border asset freezes; and
• state-entity non-cooperation.

Under Swiss law, tribunals seated in Switzerland may proceed with the arbitration even if one party fails to participate, provided that the non-participating party was properly notified and given a fair opportunity to be heard. This principle applies under both Article 182(3) of the PILA and Article 373 of the CPC, which require compliance with minimum due process standards, including the right to be heard and equal treatment. If these standards are met, the tribunal can render an award based on the submissions and evidence presented by the participating party.

In sum, non-participation does not paralyse arbitral proceedings in Switzerland, as long as procedural fairness is ensured; but tribunals must be careful to ensure procedural integrity to avoid annulment or enforcement issues.

The Swiss Rules of Arbitration of June 2021 expressly regulate this in Articles 30(2) and 30(3) and permit the tribunal to continue the proceedings and render an award even if a party fails to appear or present its case, as long as the party was properly notified and due process is upheld.

Under Swiss law, arbitrators are not immune from liability, but they can only be held liable in rare cases of gross negligence or wilful misconduct.

There is no explicit provision on liability in the PILA, but general principles of Swiss contract and tort law apply. Arbitrators are not liable for procedural errors or incorrect decisions made in good faith.

In domestic arbitration, liability is similarly limited. While the CPC does not specifically regulate arbitrator liability, Swiss mandate law (Articles 398 and 321e of the Civil Code) applies by analogy. Arbitrators must act with due care, and liability arises only in exceptional cases of serious breach.

Under Swiss law, courts do not stay proceedings; but if there is a valid and binding arbitration agreement, the court will typically decline jurisdiction and dismiss the case in favour of arbitration. This is governed by:

• Article 7 of the Private International Law Act (PILA) in international cases; and
• Article 61(1) of the Civil Procedure Code (CPC) in domestic arbitration.

The court will decline jurisdiction unless it finds the arbitration agreement to be:

• null and void;
• inoperative; or
• incapable of being performed.

This is a high threshold. Swiss courts interpret arbitration agreements broadly and favourably, in line with Switzerland’s pro-arbitration stance and the principle of favor validitatis (see question 3.1).

Importantly, the request to refer the case to arbitration must be raised before any argument on the merits in the court proceedings. A party that proceeds without objecting may be deemed to have waived its right to arbitrate.

Yes, for arbitrations seated in Switzerland, Swiss courts have certain powers to assist arbitral proceedings under both the PILA and the CPC.

These powers include:

• appointing or replacing arbitrators when the agreed procedure fails (Article 179 of the PILA or Article 362 of the CPC);
• deciding on challenges to arbitrators (Article 180 of the PILA or Article 369 of the CPC);
• granting interim relief upon request (Article 183(1) of the PILA or Article 374 of the CPC);
• enforcing interim measures or evidentiary orders (Article 184(2) of the PILA or Article 375 of the CPC); and
• ruling on applications to set aside arbitral awards (Article 190 of the PILA or Article 389 of the CPC).

International arbitration: In international arbitration, parties can limit the role of Swiss courts in certain respects. Article 183(1) of the PILA allows them to exclude court-ordered interim measures if the tribunal is empowered to grant such relief.

However, some court powers cannot be excluded. These include the power to:

• appoint or challenge arbitrators if the agreed procedure fails (Articles 179 and 180 of the PILA);
• assist with the taking of evidence or the enforcement of interim relief (Article 184 of the PILA); and
• rule on set-aside or enforcement applications (Articles 190 to 194 of the PILA).

The exception to that is that Article 192(1) of the PILA allows parties with no Swiss domicile or place of business to exclude set-aside proceedings altogether, if this is done expressly and in writing.

Domestic arbitration: Under the CPC, parties enjoy similar procedural flexibility and may not waive essential guarantees such as the right to be heard or equal treatment.

The Private International Law Act (PILA) does not contain a statutory provision on costs, but tribunals generally apply the principle that ‘costs follow the event’, ordering the unsuccessful party to bear the arbitration costs and the reasonable legal fees of the prevailing party. Arbitral tribunals can adjust this based on factors such as:

• party conduct;
• partial success; or
• procedural behaviour.

Under the Swiss Rules of Arbitration of June 2021, costs are regulated in Articles 38–41. The tribunal fixes the costs of the arbitration in the award (Article 38) and fees/expenses are set per Appendix B, considering case complexity and time spent (Article 39). Allocation follows the ‘costs follow the event’ principle, but the tribunal can adjust the cost allocation based on circumstances, including party conduct and efficiency (Article 40). Advances on costs are managed by the tribunal (after consulting the court); equal deposits may be requested and topped up, with suspension or termination if unpaid (Article 41).

In domestic arbitration, Article 384(1)(f) of the Civil Procedure Code (CPC) requires that the arbitral award include the amount and allocation of the costs of the proceedings.

In both regimes, the tribunal may order security for costs, treated as an interim measure under Article 183(1) of the PILA and Article 374(1) of the CPC.

Under both the international and domestic regimes:

• the parties enjoy wide autonomy to agree on how arbitration costs should be allocated; and
• agreements are generally respected by tribunals if they do not violate:
• • mandatory procedural principles; or
  • public policy.

However, certain restrictions apply:

• The tribunal must still ensure equal treatment and due process, meaning that cost agreements that are manifestly unfair or abusive should not be enforced; and
• Tribunals are not bound to follow agreements that would compromise their independence or impartiality, such as clauses tying arbitrator fees to the outcome of the case.

Yes, third-party funding is permitted under Swiss law for both international and domestic arbitrations seated in Switzerland. There are currently no rules or regulations prohibiting or restricting the use of third-party funding.

While there are no mandatory disclosure obligations under the Private International Law Act or the Civil Procedure Code, tribunals may require disclosure of funding arrangements, especially where they might raise conflicts of interest (eg, between a funder and an arbitrator).

International arbitration: Article 189(1) of the Private International Law Act (PILA) provides that the award must be made in the form and according to the procedure agreed upon by the parties.

If there is no such agreement, Article 189(2) of the PILA sets out certain default requirements. The award must:

• be in writing;
• be signed by the arbitrators (made by a majority decision or, in the absence of a majority, by the chairperson);
• state the date and the seat of arbitration; and
• be reasoned, unless the parties have agreed otherwise.

Article 190(2) of the PILA also sets out grounds for annulment that reflect the required procedural standards e contrario. These include compliance with:

• the right to be heard;
• equal treatment of the parties;
• respect for public policy; and
• staying within the limits of the claims submitted (no ultra petita).

Breaches of these may lead to:

• annulment of the award; or
• refusal of enforcement.

Domestic arbitration: Article 384 of the CPC applies. The CPC requires that the award be:

• in writing;
• reasoned (if nothing else is decided by the parties);
• dated; and
• signed.

The signature of the presiding arbitrator alone is sufficient.

Swiss law does not impose a statutory time limit for the issuance of an arbitral award in either the PILA or the CPC. However, the tribunal is expected to render the award within a reasonable time, taking into account:

• the complexity of the case; and
• the conduct of the proceedings.

Where institutional rules apply, a specific timeframe usually is imposed. For example, under the expedited procedure of the Swiss Rules of Arbitration of June 2021, the tribunal is expected to deliver the final award within six months of receiving the file (Article 42(2)(e)), subject to extension by the court in exceptional circumstances. There is no equivalent time limit under the standard procedure.

Yes. Under Article 190(1) of the Private International Law Act (PILA) and Article 387 of the Civil Procedure Code (CPC), an arbitral award rendered by a tribunal seated in Switzerland is considered final and enforceable upon notification, in the same way as a judgment of a Swiss state court. A separate recognition proceeding may be initiated only in exceptional cases where the applicant demonstrates a legitimate interest in obtaining recognition.

For international awards, Article 194 of the PILA directly applies the 1958 New York Convention without any reservation. A party seeking enforcement must submit an application to the competent cantonal court where enforcement is sought, together with the original or a certified copy of the arbitral award and the arbitration agreement.

The court will usually grant enforcement unless one of the limited grounds for refusal under Article V of the New York Convention is established.

For domestic awards, enforcement is governed by Article 387 of the CPC.

Where the Swiss Rules of Arbitration of June 2021 apply, Article 34(2) confirms that all awards are binding on the parties. This aligns with immediate enforceability of final awards under Swiss law.

International arbitration: In international arbitration, arbitral awards may be challenged only through a set-aside application to the Swiss Federal Supreme Court, in accordance with Article 190(2) of the Private International Law Act (PILA). When doing so:

• the review is limited to a narrow set of procedural grounds; and
• no appeal on the merits is possible.

The exhaustive grounds set out in Article 190(2) of the PILA for setting aside an award are:

• improper constitution of the tribunal;
• wrong decision on jurisdiction;
• a decision beyond the relief sought (ultra or infra petita);
• violation of the right to be heard or of equal treatment; and
• the incompatibility of the award with Swiss public policy.

However, challenges are rare and the Federal Supreme Court applies a high threshold, particularly with respect to public policy.

Domestic arbitration: For domestic arbitration, the challenge procedure is governed by Articles 389–395 of the Civil Procedure Code (CPC). The list of grounds is similar but includes a few procedural differences.

International arbitration: For international arbitration, a challenge to an arbitral award must be brought within 30 days of the formal notification of the award, as set out in Article 190(4) of the PILA.

The challenge must be filed directly to the Federal Supreme Court. The application must:

• be in writing;
• state the grounds for challenge under Article 190(2) of the PILA; and
• include a copy of the award and any relevant documents.

Importantly, only final awards (or partial awards with final effect on a specific issue) can be challenged. Procedural orders and interim decisions are generally not subject to challenge unless they meet the criteria for a preliminary decision on jurisdiction (Article 190(3) of the PILA).

Domestic arbitration: Similarly, challenges in domestic arbitration are governed by Article 389 of the CPC, but the 30-day deadline to file the challenge is set by Article 100(1) of the Federal Supreme Court Act. The procedure mirrors that for international arbitration. The challenge must:

• be filed directly to the Federal Supreme Court;
• be in writing; and
• state the limited grounds available under Article 393 of the CPC.

International arbitration: The PILA permits the parties to waive their right to challenge the award, but only under specific conditions. According to Article 192(1) of the PILA, such a waiver is valid only if neither party has its domicile, habitual residence or place of business in Switzerland at the time of the arbitration agreement (see question 9.3).

The waiver must be made expressly and is typically included in the arbitration agreement or confirmed in writing later. It excludes all grounds for setting aside under Article 190(2) PILA (including public policy), except for the right to seek revision for criminal influence under Article 190a(1)(b) of the PILA.

Domestic arbitration: In contrast, for domestic arbitration under the CPC, the parties cannot completely exclude the right to challenge an award.

Swiss arbitration proceedings are generally treated as confidential in practice, but neither the Private International Law Act nor the Civil Procedure Code expressly imposes a statutory duty of confidentiality. There is no provision requiring confidentiality of:

• the proceedings;
• the award; or
• the related documents.

However, confidentiality is widely recognised as an implied principle of Swiss arbitration, especially in institutional arbitrations where rules such as the Swiss Rules of Arbitration of June 2021 (Article 44(1)) impose a duty of confidentiality on the institution, tribunal and parties, unless disclosure is required by law or agreed otherwise.

In ad hoc arbitration, confidentiality typically arises from an explicit agreement between the parties.

Yes. Even where a general duty of confidentiality applies, exceptions are recognised under Swiss law and arbitral practice.

Disclosure may be:

• required by law, particularly in the context of enforcement or annulment proceedings before state courts; oe
• permitted where it is necessary to protect or enforce a legal right, such as disclosing the award to:
• • regulators;
  • counterparties; or
  • enforcement authorities.

Confidentiality can also be lifted by party consent.

Under Article 44(1) of the Swiss Rules of Arbitration of June 2021, disclosure is allowed:

• where it is mandated by a legal duty; or
• if the parties agree otherwise.