§ 1618.2 Filing of documents.
Primary source
Verbatim text below is from the Electronic Code of Federal Regulations (eCFR), a public-domain U.S. government work. Always verify the current version with the eCFR before relying on it for any legal matter.
Full Text
Provided,A document other than a registration card received by an element of the Selective Service System will be considered to have been filed on the date that it is received: That a document that is received which was transmitted by the United States Postal Service (USPS) and was enclosed in a cover that bears a legible USPS postmark date will be deemed to have been received on that date.
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