Whereas if the case falls under the second category (i.e., objection to scope of authority), then firstly, this objection can be raised at any time after knowing of the circumstance as recorded in Section 16(3) of the Act and secondly, this objection can be raised for the first time in collateral proceedings. The Court in Hindustan Zinc Ltd. v. Ajmer Vidyut Vitran Nigam Ltd. 5 (' Hindustan Zinc' ) dealt with the challenge to an arbitrator's appointment in the first appeal stage under Section 37 of the Act. While granting relief to the party the Court inter alia held that " if there is an inherent lack of jurisdiction, the plea can be taken up at any stage and also in collateral proceedings". The Court further relied on Kiran Singh and Others v. Chaman Paswan and Others 6 upon a judgment which held "…