Noerr-Pennington doctrine

Overview
The Noerr-Pennington doctrine is a doctrine of U.S. antitrust law set forth by the U.S. Supreme Court in a pair of cases, which suggested that under the First Amendment it cannot be a violation of federal antitrust laws for competitors to lobby the government to change the law in a way that would reduce competition. The Court later expanded on the doctrine. 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." Finally, in California Motor Transport, the Court added that "the right to petition extends to all departments of the Government [and] [t]he right of access to the courts is indeed but one aspect of the right of petition."

Expansion of the doctrine beyond the antitrust arena
Since its formulation, the doctrine has been extended to confer immunity from a variety of tort claims, including claims of unfair competition, tortious interference and abuse of process. The Ninth Circuit recently held that Noerr-Pennington also protects against RICO claims when a defendant has sent thousands of demand letters threatening suit.

Exception for sham proceedings
There is an exception to the doctrine for sham proceedings. For example, in California Motor Transport v. Trucking Unlimited, the U.S. Supreme 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.

The sine qua non of a "sham" proceeding is not the purpose to harm a competitor, but rather the absence of any purpose to actually obtain government action. Thus, initiating an administrative proceeding that one actually hopes to win in order to harm one's competitors is within the ambit of the Noerr-Pennington doctrine, while initiating a similar proceeding that one does not meaningfully intend to win solely to delay one's business competitors is within the sham exception.

In 1993 the U.S. Supreme Court rejected a purely subjective definition of a "sham" lawsuit, and set out a two-part test. Under the first prong of the test, a lawsuit fits within the "sham" exception to First Amendment immunity only if the lawsuit is objectively baseless in that "no reasonable litigant could realistically expect success on the merits." Only if the challenged litigation meets the first prong ("objectively baseless") may a court go on to the next prong, which consists of a determination of whether the litigant's subjective motivation in filing the objectively baseless lawsuit was an attempt to interfere with the business of a competitor.