(*) The current patent numbering system began with a patent issued on
July 13, 1836. Prior to that date, 9,957 patents had been issued. Defensive
Publications (T) and Improvement patents (AI) are not included in this
table.
(**) Reissue patents were not separately numbered until 1838.
Some patent numbers, as displayed in the table, are 7 characters with the
numeric portion padded with leading zeroes.
Some numbers within a series may be unused. Therefore, the number of patents
granted during a year cannot be determined by simply subtracting the number
of the first patent issued in one year from the number of the first patent
issued in the next year. The user should note that the data in this table
have been checked but that they still may not be completely devoid of
errors.