The registration, uncovered by Siliconera, lacked any other relevant details, though applications for the Existence trademark were made in both the US and Japan.

Kojima Productions recently brought the series' stealth-action antics to the PlayStation 3 through this year's long-awaited release of Metal Gear Solid 4: Guns of the Patriots.

While MGS4 was said to conclude the storyline of series protagonist Solid Snake, Payton previously stated that the series would not end there, later noting that the franchise had "a lot of room for filling in the gaps as far as [series antagonist and MGS3 lead] Big Boss is concerned."