Proof of claim process requires creditors to file Form F with documentary or information utility evidence for insolvency verification. Regulation 9A requires a creditor not covered by specified classes to submit proof of claim to the interim resolution professional or resolution professional in person, by post or electronically in Form F; the claim may be proved by information utility records or other documents such as demand papers, creditor bank statements showing non-satisfaction, or a court or tribunal order adjudicating non-satisfaction.