The assessee argues that the expression “reasons to believe” under Section 147 refers to objective circumstances. In the present case, the assessment was completed under Section 143 (3) after notice was issued under Section 142 (1) was issued and explanation sought in respect of all relevant matters. The assessee could not be faulted for the omission to discuss the materials on record. Learned counsel stressed that “reasons” were to be on the basis of “tangible materials” which must be in possession of the revenue, which alone can result in a valid re-opening. There was no such tangible material; the AO, argued counsel, acted without any jurisdiction in merely seeking to revisit the matter, which in effect amounts to a review or an impermissible change of opinion. Learned counsel relied on CIT, Delhi v. Kelvinator of India Ltd., (2010) 2 SCC 723 and CIT-V v. Orient Craft Ltd., [2013] 354 ITR 536 (Delhi). The foundation of the AO’s jurisdiction and the raison d’etre of a reassessment notice are the “reasons to believe”. Now this should have a relation or a link with an objective fact, in the form of information or facts external to the materials on the record. Such external facts or material constitute the driver, or the key which enables the authority to legitimately re-open the completed assessment. In absence of this objective “trigger”, the AO does not possess jurisdiction to reopen the assessment. It is at the next stage that the question, whether the re-opening of assessment amounts to “review” or “change of opinion” arises. In other words, if there are no “reasons to believe” based on new, “tangible materials”, then the reopening amounts to an impermissible review. Here, there is nothing to show what triggered the issuance of notice of reassessment – no information or new facts which led the AO to believe that full disclosure had not been made. The impugned notice, the AO’s order rejecting the objections, and the arguments of the Revenue nowhere indicate how the AO was impelled to seek re-opening of the assessee’s case, as distinguished from the several other completed assessments. . For these reasons, this Court is of the opinion that the impugned reassessment notice cannot be sustaine.