20 C.F.R. § 404.510a
A benefit payment under title II or title XVIII of the Act to or on behalf of an individual who fails to meet one or more requirements for entitlement to such payment or a benefit payment exceeding the amount to which he is entitled, constitutes an entitlement overpayment. Where an individual or other person on behalf of an individual accepts such overpayment because of reliance on erroneous information from an official source within the Social Security Administration (or other governmental agency which the individual had reasonable cause to believe was connected with the administration of benefits under title II or title XVIII of the Act) with respect to the interpretation of a pertinent provision of the Social Security Act or regulations pertaining thereto, or where an individual or other person on behalf of an individual is overpaid as a result of the adjustment upward (under the family maximum provision in section 203 of the Act) of the benefits of such individual at the time of the proper termination of one or more beneficiaries on the same social security record and the subsequent reduction of the benefits of such individual caused by the reentitlement of the terminated beneficiary(ies) pursuant to a change in a provision of the law, such individual, in accepting such overpayment, will be deemed to be without fault. For purposes of this section governmental agency includes intermediaries and carriers under contract pursuant to sections 1816 and 1842 of the Act.
20 C.F.R. §404.510a