This time limit, which can be modified by the parties, runs from the moment in which the answer to the statement of claims is filed or has to be filed by the respondent. The challenge of an award on this ground is one of the most controversial issues in Spanish arbitral case law. The courts of appeal have not taken a common approach, although recent decisions seem to agree that the award can be challenged on the grounds of "breach of the arbitral procedure", subject to a careful examination of the parties' conduct.

The Court of Appeal of Vizcaya followed this predominant approach and rejected the application to set aside the award. The Court emphasised that the party who challenged the award did not complain about the expiration of the time-limit during the proceedings and actually contributed by its own conduct to the delay in rendering the award. Therefore, the Court of Appeal concluded that the party had waived its right to challenge the award on the ground of breach of arbitral procedure.