<h1>Deduction for new plant and machinery requires a certified accountant's report confirming acquisition, installation and calculation eligibility.</h1> Certification under Form No. 3AA requires an accountant's report verifying new plant and machinery acquisitions and installations, separately stating deductions for new industrial undertakings and for substantial expansion of pre-existing undertakings. Deductions must be supported by Annexure A (new undertakings) or Annexure B (expansions) detailing vendor, asset, purchase and installation dates, and actual cost. The report must be signed by a Chartered Accountant or authorised auditor, declare that necessary information was obtained, state reasons for any negative or qualified answers, and apply the statutory definitions of 'actual cost' and 'substantial expansion' (minimum ten percent increase in installed capacity).