52.— (1) This section applies to a disclosure—

(a) by or on behalf of a credit institution to another credit institution,

(b) by or on behalf of a financial institution to another financial institution,

(c) by or on behalf of a legal adviser to another legal adviser, or

(d) by or on behalf of a relevant professional adviser of a particular kind to another relevant professional adviser of the same kind.

(2) It is a defence in any proceedings against a person for an offence under section 49, in relation to a disclosure to which this section applies, for the person to prove that, at the time of the disclosure—

(a) the disclosure related to—

(i) a customer or former customer of the person (or an institution or adviser on whose behalf the person made the disclosure) and the institution or adviser to which or whom it was made, or

(ii) a transaction, or the provision of a service, involving both the person (or an institution or adviser on whose behalf the person made the disclosure) and the institution or adviser to which or whom it was made,

(b) the disclosure was only for the purpose of preventing money laundering or terrorist financing,

(c) the institution or adviser to which or whom the disclosure was made was situated in a Member State or in F109[a country other than a high-risk third country], and

(d) the institution or adviser making the disclosure, or on whose behalf the disclosure was made, and the institution or adviser to which or whom it was made were subject to equivalent duties of professional confidentiality and the protection of personal data F110[…].

(3) A reference in this section to a customer of an adviser includes, in the case of an adviser who is a barrister, a reference to a person who is a client of a solicitor who has sought advice from the barrister for or on behalf of the client.