Anonymous donations tax imposes a specific surcharge and adjusts taxable income when institutions receive unidentified contributions. Where an assessee's total income includes anonymous donations, tax comprises (a) thirty per cent on aggregate anonymous donations exceeding the higher of five per cent of total donations or one lakh rupees, and (b) the income-tax the assessee would pay if total income were reduced by that excess; exclusions apply for donations to trusts or institutions established wholly for religious purposes and for religious and charitable trusts except where donations are specifically directed to a university or hospital; anonymous donation denotes contributions lacking prescribed donor identity records.