In a recent decision,(1) the Supreme Court recalled the conditions that must be met to request the revision of an international arbitral award under article 190a of the Private International Law Act (PILA), which entered into force on 1 January 2021 further to the revision of Chapter 12 of the PILA. The Supreme Court found that such conditions had not been met in the present case and dismissed the request for revision.


In arbitration proceedings before the Court of Arbitration for Sport (CAS) between a professional runner and World Athletics, by an award dated 27 August 2021, the runner was found to have violated anti-doping rules and was sanctioned accordingly.

On 17 June 2021 and 1 October 2021, the runner challenged this award before the Supreme Court. On 1 December 2021, she also filed a request for revision, to which she enclosed, among other things, an affidavit of Dr C__ dated 30 November 2021. At the runner's request, the proceedings pertaining to the challenge were suspended pending the outcome of the revision proceedings.


Under article 190a(1)(a) of the PILA, a party may request the revision of an award if it subsequently discovers relevant facts or conclusive evidence on which it was unable to rely in the previous proceedings despite having exercised due diligence, to the exclusion of facts or evidence subsequent to the award.

Revision on the grounds of discovery of new facts presupposes the fulfilment of the following five conditions:

  • The applicant invokes one or more facts.
  • These facts are "relevant" – that is, they are of such a nature as to modify the state of facts on which the award was based and to lead to a different solution in accordance with a correct legal assessment.
  • These facts already existed when the award was issued (ie, the facts are "pseudo-nova" – that is, facts that predate the decision or, more precisely, facts that occurred up to the time when, in the main proceedings, allegations of fact were still admissible).
  • These facts were discovered after the event.
  • The applicant was unable, despite all their diligence, to invoke these facts in the previous proceedings.(2)

A party will not have acted diligently where the discovery of new evidence is the result of research that could and should have been carried out in the previous proceedings, and revision should not be used to remedy the applicant's omissions in such proceedings.(3)

Revision on the grounds of discovery of conclusive evidence also presupposes that five conditions are met – namely:

  • The evidence must relate to earlier facts (pseudo-nova).
  • It must be conclusive – that is, it must be capable of leading to a modification of the award in a way favourable to the applicant.
  • It must have existed already when the award was issued (more precisely, up to the last moment when it could still be introduced in the main proceedings).
  • It must have been discovered only after the event.
  • The applicant could not have relied on it, through no fault of their own, in the previous proceeding.(4)

It is not sufficient that the arbitral tribunal has wrongly interpreted known facts; it must have done so further to its ignorance, or to the lack, of evidence of facts essential for the award.(5)

A request for revision must be filed with the Supreme Court within 90 days from the discovery of the ground for revision (article 190a(2) of the PILA), meaning from the time when the applicant has sufficiently reliable knowledge of the new fact to be able to invoke it, even if they are not able to prove it with certainty.(6)

In the present case, applying the abovementioned principles, the Supreme Court found that the applicant had not established that she had complied with the abovementioned time limit. She had merely stated that she had discovered Dr C __'s affidavit "a few days before the filing of [its] request", which did not make sense given that the affidavit was dated 30 November 2021 and the request had been filed the very next day. Furthermore, the applicant had not established when she had become aware of Dr C__'s scientific opinion (on which she had relied, as opposed to his affidavit) nor that she had taken all the steps that could reasonably be expected of her to obtain the means of proof at an earlier stage. Further, the request for revision was filed 91 days after the notification of the award.(7)

In any event, according to the Supreme Court, if the applicant had relied on the subsequent discovery of the affidavit, the request would fail because revision cannot be requested on the basis of post-award evidence.(8) Also, following the argument whereby Dr C__'s opinion had existed already during the arbitration proceedings, the request for revision would have to be dismissed, as the applicant could and should have produced written evidence from Dr C__ during the arbitration proceedings.(9) In this respect, the Supreme Court referred to a previous case, in which it had held that:

  • an expert report issued after an award in principle cannot form the basis of a request for revision;
  • revision is an extraordinary legal remedy; and
  • it is thus up to the parties to contribute in good time to the establishment of the disputed facts in accordance with the applicable procedural rules.(10)

For these reasons, the Supreme Court found that the applicant could not base her request for revision on Dr C__'s testimony, absent proof that she could not have relied on it in the previous proceedings (see the fifth condition above), and it dismissed the request for revision accordingly.(11)


This decision constitutes a good reminder of the conditions that must be met in order for a request for revision to succeed. The entry into force of new article 190a (1)(a) of the PILA, which corresponds in substance to article 123(2)(a) of the Supreme Court Act, has not changed the Supreme Court's practice, and reference may thus be made to the Supreme Court's earlier decisions issued under the auspices of the latter provision.

In view of the outcome of the request for revision, the challenge proceedings against the award (which were suspended pending the outcome of the revision proceedings) will now resume.

For further information on this topic please contact Frank Spoorenberg or Daniela Franchini at Tavernier Tschanz by telephone (+41 22 704 3700) or email ([email protected] or [email protected]). The Tavernier Tschanz website can be accessed at www.taverniertschanz.com.


(1) Supreme Court, 4A_606/2021, 28 April 2022.

(2) Ground 3.2.1.

(3) Ground 3.2.1, referring to Supreme Court, 4A_36/2020, 27 August 2020, ground 3.2.1.

(4) Ground 3.2.2 referring to Supreme Court, 4A_71/2021, 13 July 2021, ground 5.1.2.

(5) Ground 3.2.2.

(6) Ground 4.

(7) Ground 5.2.

(8) Ground 5.2.

(9) Ground 6.3.2.

(10) Ground 5.2, referring to Supreme Court, 4A_597/2019, 17 March 2020, ground 4.2.

(11) Ground 5.2.