Act of Affiliation

A individual undergoes the Act of Affiliation when they pass their Autobot Code Exam. It consists of them receiving an interim Autobot badge drawn on their person by the highest-ranking Autobot officer present.

Fiction

IDW Generation 1 continuity

Hot Rod underwent his Act of Affiliation ritual years ago, during which Optimus Prime himself drew Hot Rod's interim Autobot symbol on the young 'bot.

Ambulon had an Act of Affiliation ceremony when he defected to the Autobots.

Tailgate underwent his Act of Affiliation aboard the Lost Light, Rodimus presided over the ceremony and a number of Tailgate's friends were invited. Rodimus recounted a story of his own Act of Affliation, before writing the Autobot symbol on Tailgate. Unfortunately, due to a brief possession, Rodimus wrote "Let me out" on Tailgate in old Cybertronian instead of the Autobot symbol he had intended. You, Me, and Other Revelations

Notes

During Tailgate's ceremony Rodimus stated that Ambulon was the last to have it performed ten years ago. Though the timings in and around All Hail Megatron are a bit confused it seems like Drift must have missed out on his as it he joined the Autobots during these years.