35 Pa. Stat. § 1680.506a
The creation of the agency is in all respects for the benefit of the people of the Commonwealth and for the improvement of their health, safety, welfare, comfort and security, and its purposes are public purposes and the agency will be performing an essential governmental function. The Commonwealth covenants with the purchasers and all subsequent holders and transferees of the notes and bonds issued by the agency, in consideration of the acceptance of any payment for the notes and bonds, that the notes and bonds of the agency, issued pursuant to this act and the income therefrom, the income and revenues of the agency, and the agency and its property shall at all times be free from taxation or assessment of every kind and nature except for inheritance, estate, gift and transfer taxes.
35 P.S. § 1680.506a