How long does a Secrecy Order remain in effect?

Under 35 U.S.C. 181, a Secrecy Order remains in effect for a period of 1 year from its date of issuance. It may be renewed for additional periods of not more than 1 year upon notice by a government agency that the national interest requires it. The applicant is notified of any renewal. (MPEP 120 Section VII)