72 Pa. Stat. § 7275
Notwithstanding the provisions of section 274, the department may permit the Commissioner of Internal Revenue of the United States, or the proper officer of any state, or the authorized representative of either such officer, to inspect the tax returns of any taxpayer, or may furnish to such officer or to his authorized representative an abstract of the return of any taxpayer, or supply him with information concerning any item contained in any return or disclosed by the report of any examination or investigation of the return of any taxpayer. This permission shall be granted only if the statutes of the United States or of such other state, as the case may be, grant substantially similar privileges to the proper officer of the Commonwealth charged with the administration of this article.
72 P.S. § 7275