An official form submitted by a creditor setting out the basis and amount of its claim against a debtor in a bankruptcy case. The proof of claim form is Official Bankruptcy Form B 410. The purpose of a proof of claim is to give notice of the claim to the court, the debtor, the trustee and other creditors. A properly prepared proof of claim constitutes prima facie evidence of the validity and amount of the claim and is deemed allowed, unless a party in interest (such as the debtor) objects. For further information, see Practice Note, Filing a Proof of Claim in a Chapter 11 Bankruptcy Case.