Can the certificate of mailing by first class mail procedure be used for PCT applications?
The certificate of mailing by first class mail procedure (37 CFR 1.8) cannot be used for filing papers during the international stage of PCT applications if the date of deposit is to be considered as the filing date. MPEP 1834 clearly states:
“It is important to understand that the 37 CFR 1.8 certificate of mailing procedure CANNOT be used for filing any papers during the international stage if the date of deposit is desired.”
If the 37 CFR 1.8 procedure is used, the paper will be accorded the date of receipt at the USPTO, not the date of mailing. This could result in late filing if the paper is not physically received by the due date. Therefore, applicants should use other methods, such as Priority Mail Express®, for time-sensitive PCT filings.
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