Keystone Bituminous Coal Ass'n v. DeBenedictis, 480 U.S. 470 (1987), is a United States Supreme Court case interpreting the Fifth Amendment's Takings Clause.

In this case, the court upheld a Pennsylvania statute which limited coal mining causing damage to buildings, dwellings, and cemeteries through subsidence.

Some examples of coal mine subsidence damage include cracked foundations, sinkholes, and groundwater loss.

However, surface owners generally waived any claims against petitioners or prior coal companies for damages caused by mining.

In answers to interrogatories, the petitioners claimed that from 1966 to 1982 their land use rights at their 13 coal mines had been restricted to the point of a taking because of the Subsidence Act.

However, the Court began its opinion by rejecting the petitioners' argument that Pennsylvania Coal Co. v. Mahon should control in this case because "[T]he similarities .

'"[6] Using the two factors above, the Court found that the petitioners didn't meet their burden of proof in order to establish a taking.

[7] The Court found that the Subsidence Act "substantially advanced legitimate state interests" by trying to prevent "a significant threat to the common welfare" and that it wasn't "impossible for petitioners to profitably engage in their business."

The Court stressed that the Kohler Act was not a legitimate exercise of the State's police power because it was only meant to protect "some private landowners' homes."

Conversely, the Subsidence Act was a legitimate exercise of the State's police power because it was meant "to protect the public interest in health, the environment, and the fiscal integrity of the area."

In this case, the Court deferred to the Pennsylvania Legislature's finding "that important public interests are served by enforcing a policy that is designed to minimize subsidence in certain areas" because this purpose was "genuine, substantial, and legitimate.

Therefore, during the 44 years between the Pennsylvania Coal Co. v. Mahon decision and the enactment of the Subsidence Act there was a change in the public's attitude toward regulations affecting private land.

In this case, the Court held that there is not a taking if "the State merely restrains uses of property that are tantamount to public nuisances.

Here, the Court held that there was no "show[ing of] any deprivation significant enough to satisfy the heavy burden placed upon one alleging a regulatory taking."

[11] So, the Court found that the 27 million tons of coal to be left in place was not "a separate segment of property for takings law purposes."

[12] Finally, the petitioners' Contract Clause violation claim alleged that Section 6 of the Subsidence Act interfered with the liability waivers that they had with surface property owners.

Rejecting this claim, the Court held that the state's "strong public interest" in preventing subsidence outweighed any contractual obligations between surface property owners and the petitioners.

To begin with, Rehnquist attacked the majority's view that Justice Holmes' opinion in PA Coal was "uncharacteristically ...

In fact, he found the majority's opinion "particularly disturbing" and believed that their disregard for Pennsylvania Coal Co. v. Mahon essentially ignored a case that "for 65 years [had] been the foundation of [the Court's] 'regulatory takings' jurisprudence."

He pointed to the often quoted phrase from Pennsylvania Coal Co. v. Mahon that "'if regulation goes too far it will be recognized as a taking'" and listed five cases where it had been relied on in reaching an outcome.

Rehnquist was very troubled by the fact that Pennsylvania Coal Co. v. Mahon had been cited and relied on as precedent in previous takings cases, but was now only considered to be advisory.

[13] Rehnquist also disagreed with the majority because he felt that the Kohler Act in Pennsylvania Coal Co. v. Mahon was intended to benefit private parties and the general public.

Finally, Rehnquist argued it was incorrect for the majority to overlook Pennsylvania's three defined property interests.