The Vault-Tec Corporation is an unseen, Earth-based organization, and an Easter Egg in the 2016 reboot of the Doom series.
The Vault-Tec Corperation appears as an easter egg via a Logo Sticker in The UAC on a door, whilst appearing on the Vault-Guy collectible Marine figure, wearing the blue, and yellow company scheme.
Behind the scenes
Vault-Tec originated from the Fallout series of role-playing video games, where they are prominently featured or referenced in every major installment. They are the notorious creators of the underground fallout shelters (known as "Vaults") that dot the United States of America.