Nobody owns the origin point of the modern zombie, Night of the Living Dead.

A copyright notice was indeed placed in the print of the film, along side the title that the filmmakers had given it, Night of the Flesh Eaters.

When the distributor of the film, the Walter Reade Organization, realized that there had already been a movie called The Flesh Eaters, they changed the title, but they forgot to put a copyright notice on the new frames. Nobody noticed at the time, and it went out to theaters. In 1968, that meant the entire movie was accidentally placed in the public domain.

Later, a colorized version and a remake were both made in attempts to reestablish a kind of copyright, but that original cut remains under nobody's creative control. That's why, for example, James Riffel could use all that footage in 1991 and replace the audio track to create a new work, Night of the Day of the Dawn of the Son of the Bride of the Return of the Revenge of the Terror of the Attack of the Evil, Mutant, Alien, Flesh Eating, Hellbound, Zombified Living Dead Part 2: In Shocking 2-D. Unfortunately, that is under copyright, so I can only post the trailer.