How does the USPTO handle mail received on weekends or holidays?

The USPTO does not officially receive mail on weekends or federal holidays when the office is closed. Any correspondence received on these days is typically stamped with the next business day’s date. For example, if mail is delivered to the USPTO on a Saturday, it will be stamped with the following Monday’s date (or Tuesday if Monday is a holiday). This practice ensures consistency in dating received documents and aligns with the USPTO’s official business hours.