Development rebate reserve requirement restricts distribution and remittance and conditions depreciation allowance upon reserve utilisation over set period. Section 34 conditions depreciation and development rebate deductions on charging a required portion of the rebate to profit and loss and crediting it to a reserve to be used in the business over eight years, prohibiting use for dividend distribution or remittance abroad; reduced rebate treatment and specified exceptions apply. Disposal of the relevant asset within eight years renders prior allowances wrongly made and invokes section 155(5), subject to exceptions for pre cut off acquisitions, transfers to government or specified corporations, and transfers in amalgamation or succession.