Held, that there could be two sets of situations possible, viz. (i) that the Assessing Officer having jurisdiction over the case of the assessee had failed to obtain the requisite sanction under section 151 of the Act from the Principal Commissioner qua his “reasons to believe” and had issued the notice under section 148 ; or (ii) that the ITO, Ward-1(3), had proceeded with on the basis of the sanction under section 151 obtained by the ITO, Ward-2(1), and dispensed with the statutory requirement of obtaining separate sanction qua the “reasons to believe”. In either of the situations, the assumption of jurisdiction by the ITO, without obtaining the requisite sanction, was devoid and bereft of any force of law. If the ITO, had pre-empted the grant of sanction by the Principal Commissioner and, prior to obtaining, had issued the notice under section 148, the reassessment notice issued was invalid in the eyes of the law. (AY.2010-11)