46 CFR §2.95-1

1. (a)Certificates or documents issued to the public, as required by laws, rules, or regulations, shall be retained for the applicable period of time, as follows:
   1. (1)If the certificate or document specifies a definite period of time for which it is valid, it shall be retained for so long as it is valid unless it is required to be surrendered; or,
   2. (2)If the certificate or document does not specify a definite period of time for which it is valid, it shall be retained for that period of time such certificate or document is required for operation of the vessel; or,
   3. (3)If the certificate or document is evidence of a person's qualifications, it shall be retained for so long as it is valid unless it is required to be surrendered.
2. (b)Nothing in this section shall be construed as preventing the Coast Guard from canceling, suspending, or withdrawing any certificate or document issued at any time.