Article in New Scientist says:
The hyper-secretive US National Security Agency – the government’s eavesdropping arm – appears to be having its patent applications increasingly blocked by the Pentagon. And the grounds for this are for reasons of national security, reveals information obtained under a freedom of information request.
Most Western governments can prevent the granting (and therefore publishing) of patents on inventions deemed to contain sensitive information of use to an enemy or terrorists. They do so by issuing a secrecy order barring publication and even discussion of certain inventions.
Experts at the US Patent and Trademark Office perform an initial security screening of all patent applications and then army, air force and navy staff at the Pentagon’s Defense Technology Security Administration (DTSA) makes the final decision on what is classified and what is not.
Read it here.