After anthrax was found in some mail delivered to the U.S. government, mail addressed to the U.S. Patent and Trademark Office was irradiated prior to delivery. Some such mail was returned to patent practitioners charred beyond recognition. Attorneys became concerned with delivery of mail and took to alternate delivery means. Some attorneys would fax documents to the U.S. Patent and Trademark Office or would fax the documents to local associates for hand delivery. Attorneys also submitted duplicate filings for submissions presumed to be lost, often by fax. The U.S. Patent and Trademark Office put liberal procedures into place to help applicants whose mail was not delivered due to irradiation. These procedures can be found here:
http://www.patentsusa.com/20011220_Anthrax_Irradiation.pdf
If a duplicate was filed, along with a signed statement in a fax cover sheet saying that the fax was a copy of correspondence mailed on a previous date, the U.S. Patent and Trademark Office considered the submission to be filed on the stated earlier date.
