What is the “mailbox date” for international applications entering the national stage?

The “mailbox date” for international applications entering the national stage is an important concept in patent examination. According to MPEP 1893.01:

“The “mailbox date” is the date of receipt of the national stage papers by the Office.”

This date is significant because it determines whether the application has met the 30-month time limit for entering the national stage. If the papers are received after the 30-month period has expired, the application may be considered abandoned.

To learn more:

• mailbox date
• national stage
• international applications
• PCT