Nikkei.com is reporting that General Dynamics and Mitsubishi Heavy Industries are teaming up to work on the Marine Corps Amphibious Combat Vehicle.
The above pics illustrate what I believe is going on here.
Mitsubishi is currently developing a heavy wheeled 8x8 capable of carrying 11 soldiers. Could they be working on an amphibious version of the same vehicle? I don't know but if they're successful...even if the Marine Corps doesn't select it...then Mitsubishi should have a leg up on the obvious Japanese Self Defense Force's need for an ACV of their own.
Sidenote: RPG cage and ERA blocks? That's alot of add on weight to an already large vehicle! A wheeled APC topping 40 tons? Read Army Recognition's info on Mitsubishi's proposed APC here.