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17 U.S. Code § 709 - Delay in delivery caused by disruption of postal or other services

In any case in which the Register of Copyrights determines, on the basis of such evidence as the Register may by regulation require, that a deposit, application, fee, or any other material to be delivered to the Copyright Office by a particular date, would have been received in the Copyright Office in due time except for a general disruption or suspension of postal or other transportation or communications services, the actual receipt of such material in the Copyright Office within one month after the date on which the Register determines that the disruption or suspension of such services has terminated, shall be considered timely.