For good cause, any memorandum or certificate issued under this subpart shall be surrendered to the Area Director of the Classing Office which issued it, upon the Area Director's request or upon the request of the Director. A new memorandum or certificate complying with this subpart may be issued in substitution therefor. If such memorandum or certificate be not surrendered upon such request, it shall nevertheless be invalid for the purposes of the act and this subpart.
[52 FR 30882, Aug. 18, 1987]