Cost audit XBRL filings must include a digitally signed XBRL cost audit report and mandatory company and auditor details. Form I XBRL prescribes electronic filing of a cost audit report in XBRL format with mandatory company identification, financial year, product group and detailed cost auditor information, and requires disclosure of any qualifications, reservations or observations in the cost auditor's report. Filers must attach the XBRL converted copy of the duly signed cost audit report, confirm use of the notified XBRL taxonomy, and provide digital signatures and identity particulars of authorised company officers and the cost auditor for verification.