Confidentiality of taxpayer information: disclosure barred except for specified enforcement, audit, intergovernmental and operational exceptions. Confidentiality of information furnished under the Act is mandated and officers are not to be compelled to produce or testify about such particulars, subject to specified exceptions permitting disclosure for prosecution, anti corruption inquiries, intergovernmental implementation, lawful service of notices or recovery, civil suits involving the government, audit of tax receipts or refunds, disciplinary and conduct inquiries, contracted automated system operation under confidentiality, and publication of aggregated class information in the public interest.