74 Pa. C.S. § 1781
The effectuation of the authorized purposes of an authority created or continued under this chapter shall and will be in all respects for the benefit of the people of this Commonwealth, for the increase of their commerce and prosperity and for the improvements of their health and living conditions, and, since an authority will, as a public instrumentality of the Commonwealth, be performing essential governmental functions in effectuating such purposes, such an authority shall not be required to pay any taxes or assessments of any kind or nature whatsoever, now in existence or to be enacted in the future, whether imposed by the Commonwealth or by any government agency upon any property or the income therefrom acquired or used or permitted to be used by an authority for such purposes, and the bonds issued by any authority, their transfer and the income therefrom, including any profits made on the sale thereof, shall at all times be free from State and local taxation within this Commonwealth. This exemption shall not extend to gift, estate, succession or inheritance taxes or any other taxes not levied directly on the bonds, the transfer thereof, the income therefrom or the realization of profits on the sale thereof.
74 Pa.C.S. § 1781