How does the Certificate of Mailing or Transmission affect filing date calculations?

The Certificate of Mailing or Transmission can affect filing date calculations in several ways:

1. For timely filing: If a paper with a certificate is received after a deadline but the certificate date is within the deadline, the paper is considered timely filed. The MPEP states: “If the date stated is within the period for reply, the reply in most instances will be considered to be timely.”
2. For actual receipt date: The USPTO will continue to stamp the actual date of receipt on all papers. According to the MPEP: “The receipt date stamped on all papers will also be the date which is entered on Office records and from which any subsequent periods are calculated.”
3. For subsequent deadlines: If a paper starts a new period for reply, that period is calculated from the actual receipt date, not the certificate date. For example: “If the last day to reply to a final Office action was November 10, 2014, and applicant deposited a Notice of Appeal with fee in the U.S. mail on November 10, 2014, and so certified, that appeal is timely even if it was not received in the U.S. Patent and Trademark Office until November 12, 2014. Since the date of receipt of the notice of appeal will be used to calculate the time at which the brief is due, the brief was due on January 12, 2015.”

It’s important to note that while the certificate can establish timely filing, it doesn’t change the actual receipt date for other USPTO processing purposes.