Namco Bandai Europe has apparently filed a trademark for something called “Soldier’s Soul” recently. Being the publisher of the Dark Souls series, a lot of people are speculating that this might be some sort of new Souls project.
Though it really should be noted that this is purely speculation, after all “Soldier’s Soul” is a little generic sounding and could be anything. At the same time though a Dark Souls 3 seems inevitable, even in the wake of From Software’s new project Bloodborne.
[Source]