The Assessing Officer initiated reassessment proceedings on the ground that the assessee had failed to file several details pertaining to its claim of deduction under section 54 of the Act such as proof of cost of improvement etc. Held that the assessee’s computation of capital gains after considering the deduction claimed under section 54 of the Act was on record. Further, the details regarding the cost were also filed. Therefore, the Assessing Officer proceeded on a wrong presumption that the details were not on record. Accordingly, he could not have recorded a reason to believe that income chargeable to tax had escaped assessment and the proceedings were to be quashed.  (AY. 2012-13)