Independent Oil and Gas Association of Pennsylvania v. Board of Assessment Appeals of Fayette County , 780 A.2d 795 (2001).

Plaintiff owners of interest in oil and gas filed action for declaratory judgment and equitable relief, alleging that imposition of ad valorem taxes was unauthorized. The court held that oil and gas interests could be subject to assessment and taxation as real estate.

Pennsylvania law recognizes three separate estates of land: the surface itself, the right of support and the minerals contained thereunder. The court noted that, "Oil and gas interests could be subject to assessment and taxation as real estate, as the statute authorizing taxation of real estate specifically enumerated ‘land’ as a subject of taxation, and included therein were interests in the minerals oil and gas." Id . at 798.

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