Under the Invention Secrecy Act of 1951,
the government may impose a secrecy order on patent applications
submitted to the Patent Office whenever the disclosure of the
inventions described in such applications "might be detrimental to the
At the end of Fiscal Year 2006, there were 4,942 secrecy orders in
effect, a slight increase from the previous year's total of 4,915,
according to data provided to Secrecy News by the U.S. Patent and Trademark Office under the Freedom of Information Act (and very promptly, too).
During 2006 itself, 108 new invention secrecy orders were imposed,
while 81 were rescinded. The precise character of the inventions that
were subjected to new controls could not be ascertained, which is the
whole point. However, it should be possible, if logistically
challenging, to identify inventions that were formerly subject to a
secrecy order but are no longer. We haven't tried to do so lately. But
they typically involve technologies that have specific military
The large majority of invention secrecy orders are imposed on patent
applications in which the government has a property interest, perhaps
having funded the development of the invention. But each year, there
are also so-called "John Doe" secrecy orders which prohibit the
disclosure of inventions created by private inventors or businesses
where the government has no property interest, thereby raising thorny First Amendment issues. In 2006, there were 29 new "John Doe" invention secrecy orders.
The latest statistics and other background on invention secrecy can be found here.