Scourge's grill is decorated with insignias taken from his slain enemies. The insignias are of various factions from Transformers history: Autobot, Decepticon, Maximal, Predacon, Mercenary, Terrorcon, and Wrecker.
During filming in Peru, a Peruvian child showed his Transformers drawings to director Steven Caple Jr., and in response, Caple invited him to the premiere, and paid to renovate his school's roof.
When Scourge taunts Optimus Prime by saying "Primus would be ashamed", this marks the first time that the Transformers' creator god from the 1980s Marvel Comic series, Primus, is mentioned in the live-action movies. According to most versions of Transformers lore, Primus was the ancient rival or brother of the evil Unicron. Both were cosmic beings who battled across different universes, until their souls were trapped in two asteroids that they turned into planets over time. Primus became the planet Cybertron where he created the thirteen Primes, robotic deities who then created the different Transformers types.
According to Steven Caple Jr., Optimus Prime's face in this movie is visually based on his voice actor Peter Cullen.
Elena reads an online paper about ancient artifacts, and the authors of the paper have the last names Takara and Tomy. These are the names of two toy companies (merged in 2005) that produce and design Transformers in Japan.