Return filing obligation: specified taxpayers must file income tax returns when statutory thresholds, foreign assets, or prescribed conditions apply. Return filing obligations require specified persons to furnish returns in the prescribed form and by the due date where statutory conditions are met: companies and firms for any income or loss; individuals, HUFs, AOPs, BOIs and artificial juridical persons when total income before certain exemptions/deductions exceeds the maximum non-taxable limit; and other triggers such as foreign asset holdings, signing authority in foreign accounts, certain bank deposits, travel or electricity expenditures, turnover/receipt thresholds, and aggregate TDS/TCS. Belated and revised returns are permitted within prescribed assessment-year limits, and audited assessees must submit tax audit reports before the return due date.