Under Section 11(3), when parties fail to agree on an appointment procedure for a three-arbitrator tribunal, what is the default procedure? 

Section 11(3) provides: "Failing any agreement referred to in sub-section (2), in an arbitration with three arbitrators, each party shall appoint one arbitrator, and the two appointed arbitrators shall appoint the third arbitrator who shall act as the presiding arbitrator." This procedure ensures balanced representation and party autonomy. However, if a party fails to appoint within 30 days of request, or if the two arbitrators fail to agree on the third within 30 days of their appointment, appointment is made by the Chief Justice or High Court, or a person/institution designated by them.