The Invention Secrecy Act of 1951 is a body of United States federal law designed to prevent disclosure of new inventions and technologies that, in the opinion of selected federal agencies, present a possible threat to the "national security" of the United States.
The U.S. government has long sought to control the release of new technologies that could present a danger to national defense and stability. During World War I, Congress authorized the United States Patent and Trademark Office (PTO) to classify certain defense-related patents. This initial effort lasted only for the duration of that war but was reimposed in October 1941 in anticipation of the U.S. entry into World War II. Patent secrecy orders were initially intended to remain effective for two years, beginning on July 1, 1940, but were later extended for the duration of the war.
The Invention Secrecy Act of 1951 made such patent secrecy permanent. Under this Act, defense agencies provide the PTO with a classified list of sensitive technologies in the form of the "Patent Security Category Review List" (PSCRL). The decision to classify new inventions under this act is made by "defense agencies" as defined by the President. Generally, these agencies include the Army, Navy, Air Force, National Security Agency (NSA), Department of Energy, and NASA, but even the Justice Department has played this role.
A secrecy order bars the award of a patent, orders that the invention be kept secret, restricts the filing of foreign patents, and specifies procedures to prevent disclosure of ideas contained in the application. The only way an inventor can avoid the risk of such imposed secrecy is to forego patent protection.
By the end of fiscal year 1992, the number of patent secrecy orders stood at 6,102. Many such orders were imposed on individuals and organizations working without government support. This number continues to grow.
The types of inventions classified under this Act is itself a secret, but presumably include a wide range of cutting-edge technologies that are related to energy generation, munitions and explosives, cryptography, aerospace transportation and electronics.