Agency, the Internal Revenue Service or the Bureau of Alcohol, Tobacco and Firearms of the United States Department of the Treasury or any agent or agency designated under the laws of any territory, state or political subdivision to administer the tax laws of that territory, state, or political subdivision.
Inspect, permission to inspect a tax return shall include permission to receive copies of the tax return upon payment of the required fee.
Returns, is any tax return, tax information return, or declaration, together with any schedules, lists or other statements designed to be supplemental to, or to become a part of, such return, which are filed with the Commissioner. In addition, a return includes information developed by the Department of Corporations and Taxation based on material filed, or required to be filed, with the Commissioner, or based on information received from the Internal Revenue Service or any other taxing authority or derived from any other source.
830 CMR, § 62C.22.1