During assessment, the AO raised a query regarding deduction under S.36(1)(viia). The assessee replied and furnished details. The assessment accepted the position. Subsequently, a notice under s.148 was issued to withdraw the deduction. The Court held that once a query is raised and responded to in the assessment proceedings, the matter becomes part of the AO’s consideration. A mere change of opinion does not constitute a reason to believe that income has escaped assessment. Reopening on the same facts without fresh material is unjustified, and the notice under s.148 was invalid. (AY. 2010-11)