S. 147 : Reassessment-Non-existent reason-Indexation cost was raised in the recorded reason–Court cannot allow the AO to improve upon the reasons in order to support the notice of reassessment- Execution of sale deed by virtue of the judgement of the High Court would relate back to the original agreement to sale, and the assessee is entitle to claim the benefit of cost of indexation from the said date. [S. 2(47), 45, 48, 148]