Privacy Protection Act of 2003 - Amends the Gramm-Leach-Bliley Act regarding mandatory Federal standards for financial institutions with respect to privacy and confidentiality of customers' nonpublic personal information, including information sharing among financial affiliates. Exempts from the Act's requirements and prohibitions (by excluding from its definition of "financial institution") any provider of financial services (or affiliate) subject to regulation of client confidentiality that prohibits unauthorized disclosure of confidential client information without the client's consent in the form of laws, rules, or regulation of professional conduct or ethics promulgated by the highest appellate court authority, or by the principal legislative or regulatory body of a State or territory of the United States, or by Federal law.