On June 28, 2016, the Osaka High Court rendered a decision to set aside an arbitral award issued by arbitrators in an arbitration case at the Japan Commercial Arbitration Association. Jones Day Tokyo, representing the appellant (a petitioner requesting that the arbitral award be set aside), brought attention to the fact that a law firm for which the presiding arbitrator worked represented a sister company of the opposing party in a U.S. class action lawsuit, and argued that the fact that the presiding arbitrator failed to disclose such information to the parties was tantamount to a procedural breach. Jones Day Tokyo also filed several foreign judicial cases referencing similar issues and collaborated on those cases with other offices of Jones Day. As a result, the Osaka High Court agreed with Jones Day's assertions and rendered a decision to set aside the arbitral award, which, we note, is only the second instance in which a Japanese court has set aside an arbitral award since the new Arbitration Law came into force.