Trademarks have been discovered for Dragon's Dogma Online in both the Japanese trademarks office and its US equivalent, the United States Patents and Trademarks Office (USTPO).
The findings come after a similar listing was found at the start of December on the EU's Office for the Harmonisation of the Internal Markets (OHIM).
Capcom has been quiet on future projects relating to the Dragon's Dogma franchise, and registering a trademark in one territory is usually enough to cover potential IP infringements, suggesting it may be an actual concept being considered by the Japanese publisher or a full blown game in development.
OHIM's listings have been dubious in the past, with several fake Fallout 4 listing made, but the USTPO is typically more stringent when it comes to trademarks on its site. That said, a search of the USTPO's website yielded no results for Dragon's Dogma Online.
You can check out both the Japanese and US listings on Dualshockers.