Approval under section 35(1)(iii) requires institutions to maintain separate research accounts and file annual returns and audited accounts. Approval under section 35(1)(iii) was granted to The Association for the Welfare of Persons with a Mental Handicap in Maharashtra, Bombay, as an Institution, conditional on maintaining a separate account for scientific research, furnishing annual returns of research activities by 31 May, submitting audited annual accounts and balance sheet to the prescribed authority by 30 June with copies to the Central Board of Direct Taxes and the concerned Commissioner, and applying three months before approval expiry for extension.