Vogsphere Inc.

"Planet Earth" was trademarked by Vogsphere Inc.. (WC: Tom Baker stars in John Lloyd's lost Doctor Who adventure, The Doomsday Contract)

Behind the scenes
Vogsphere Inc. is an obvious reference to the Vogsphere, the home planet of the Vogons from The Hitchhiker's Guide to the Galaxy. Despite the aforementioned story also being depicted as a work of fiction within Tom Baker stars in John Lloyd's lost Doctor Who adventure, The Doomsday Contract, it hints towards Doctor Who and The Hitchhiker's Guide to the Galaxy sharing a universe, as Douglas Adams himself implied several times within his works.