Allowing the petition the Court held that where assessee had disclosed truly and fully material facts pertaining to deduction claimed under section 80-IB(10) and same were carefully scrutinized by Assessing Officer and he had taken a view that assessee would be entitled to deduction under section 80-IB(10), assessment sought to be reopened on account of change of opinion of Assessing Officer about manner of computation of deduction under section 80-IB(10) was not justified.