That is a misunderstanding of the 'ownership' of Boxer. It is split between KMW - Krauss-Maffei Wegmann and Rheinmetall. Generally speaking KMW are responsible for the hull and Rheinmetall the payload modules\turret. Please note the exact relationship is blurred due to work share agreements etc on particular projects. In the UK KMW through their subsidiary company WFEL are building 'half' and Rheinmetall through their subsidiary RBSL are also building 'half'. There are of course further subcontractors involved building components like Pearson.
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