Trade Law Improvement Act of 1986

Trade Law Improvement Act of 1986 - Amends the Tariff Act of 1930 to provide that merchandise imported into the United States by, or for the use of, a Federal agency shall not be exempt from the imposition of countervailing duties or antidumping duties. Requires a person that provides factual information to the administering authority or the International Trade Commission (ITC) with respect to countervailing duty or antidumping duty investigations to certify such information as being accurate and complete. Permits the disclosure of confidential information (including verified information) by the administering authority or the ITC under an appropriate protective court order.

Allows a person to bring a civil action for damages in a district court of the District of Columbia or in the Court of International Trade for injuries sustained to his or her business or property as a result of fraud under the U.S. customs laws.

Amends Federal law to prohibit a person from importing or selling within the United States articles that are manufactured in a foreign country if: (1) such article is imported or sold in the United States at a price which is less than the foreign market value of such article; and (2) such importation or sale causes or threatens material injury to U.S. industry or labor or prevents the establishment or modernization of a U.S. industry. Allows a person whose business or property has been injured by reason of such importation or sale to bring a civil action for damages in the district court of the District of Columbia or the Court of International Trade against a manufacturer, importer, or exporter of such articles. Provides that the standard of proof in such actions is by a preponderance of the evidence. Sets forth the statute of limitations for such actions. Allows the United States to intervene as a matter of right to protect its interests with resepct to countervailing duty or antidumping duty proceedings under this Act.