A group of dissatisfied final club members started the Signet in 1870, when some juniors became fed up with the traditional social strata on campus and decided to form a new organization with a membership based on "merit and character," according to a piece written by member Nathan C. Shiverick '52 on the Society's centennial. Now 116 years old, the Signet is located in yellow cottage at 46 Dunster Street, a building it bought from the AD Club in 1902.

In the late 19th century, final clubs at Harvard were the all-male preserves of seniors only. Students would embark on their social careers in sophomore clubs like the Hasty Pudding, Pi ETA, or Institute of 1770, and then join waiting clubs as juniors. Only a few select seniors would eventually join final clubs.

Today all nine exclusive all-male clubs--as well as the Hasty Pudding, the Pi ETA, and the Signet--accept members from all classes except the freshmen class. The Harvard Lampoon selects its membership from all four classes.

In 1869, a group of sophomores led by Charles Joseph Bonaparte, who would eventually become Secretary of the Navy and then attorney general under Teddy Roosevelt, decided to boycott the 100-year-old Hasty Pudding and join the much younger Pi Eta Club. Not satisfied there, they dropped out. In reaction, the Hasty Pudding and Pi Eta clubs acted to prevent Bonaparte and his friends from joining any of the junior waiting clubs. And so the Signet was born as a juniors-only club.

The original charter included a "Hasty Pudding clause" which excluded former members of the Hasty Pudding from membership in the Signet, but that restriction no longer holds.