No easy answer here. This seems like a soap opera called "How the Plastic Turns."
Tamiya is the distributer for Italeri in Japan. You will see Italeri kits in Tamiya boxes there. Tamiya's original M242 Hummer was an Italeri kit.
Italeri provided parts of kits (M4A1 Sherman lower hull and running gear) to Dragon/DML/Shanghai Dragon Sherman kits.
Revell of Germany sells Dragon/DML/Shanghai kits in RoG boxes.
Revell of Germany sells Italeri kits in RoG boxes (sometimes adding German specific fitting on a separate sprue and Diehl tracks).
Revell of Germany boxes the AFV Club M88A1 with German specific fittings.
Revell of Germany reboxes the old Monogram M34 and Willys MB Jeep kits.
Revell of Germany reboxes the old Esci M60A3 kit.
Italeri reboxes the old Esci M60A1 and M60 Blazer kits as well as the old Esci 1/72 scale kits.
Italeri and Zvezda box one another's kits in each other's boxes.
Zvezda reboxes old Dragon/DML/Shanghai modern Soviet kits.
Academy used to copy Tamiya kits but now do their own decent kits.
Trumpeter used to copy Tamiya and Academy kits but now do their own kits.
AMT/Ertl did rebox Esci kits, but now Italeri owns the Esci armor molds.
Revell and Monogram have merged and are now Revell-Monogram. The old kits pop up in the other's box to make folks think they are new. Revell has the old Renwal kits and releases them on occasion. Some (M41, M42 and M47) have popped up in Matchbox as well as Revell of Germany boxes. Monogram has the old Aurora molds and has released the old 1/48 scale Aurora M4A3E8 and Panther at least once.
There is some Matchbox-Revell of Germany-Airfix connection where these kits pop up in one another's boxes.
You don't even want to try to figure out the Eastern European companies like Techmod, Alan, Mirage, RPM, Toga, AER....it'll make your head spin.