Noerr-Pennington doctrine

The Noerr-Pennington doctrine is a doctrine of United States antitrust law set forth by the United States Supreme Court in a pair of cases which held that under the First Amendment, it can not be a violation of the federal antirtrust laws for comptitors to lobby the government to change the law in a way that would reduce competition.

The cases are Eastern Railroad Presidents Conference v. Noerr Motor Freight, Inc., 365 U.S. 127 (1961), and United Mine Workers v. Pennington, 381 U.S. 657 (1965). In Noerr, the Court held that "no violation of the [Sherman] Act can be predicated upon mere attempts to influence the passage or enforcement of laws". Similarly, the Court wrote in Pennington that "[j]oint efforts to influence public officials do not violate the antitrust laws even though intended to eliminate competition."

There is an exception to the doctrine for sham proceedings. For example, in California Motor Transport v. Trucking Unlimited, 404 U.S. 508 (1972), the Court held that the Noerr-Pennington doctrine did not apply where defendants had sought to intervene in licensing proceedings for competitors, because the intervention was not based on a good-faith effort to enforce the law, but was solely for the purpose of harassing those competitors and driving up their costs of doing business.