Arbitration agreements referring to non-existing arbitral institutions or including undefined references to arbitral institutions are significantly observed in international arbitration practice. Validity of such arbitration agreements becomes debatable due to the pathological intent thereof. If the pathology may be resolved by way of interpretation in the manner that leaves no room for doubt, the ideal solution is resolution of such problems by way of interpretation by means of supporting parties' common intent towards arbitration and of protecting legitimate expectations of parties in compliance with bona fides principle, without reference to any law applicable. However, if interpretation of an undefined reference in an arbitration agreement leads to an uncertainty about competence of certain arbitral institutions, such arbitration agreement aimed at institutional arbitration either may be accepted to be turned into an arbitration agreement aimed at ad hoc arbitration or may be held null-andvoid, depending on position of law of seat of arbitration. In addition to the pathology about arbitral institution referred to in arbitration agreement, if seat of arbitration is also undefined or non-existing, arbitration agreement shall be held incapable of being performed and null-and-void