Mitsubishi Motors, a junior partner of Nissan Motor, is reportedly considering not joining the merger between Nissan and Honda Motor. This decision comes as Mitsubishi seeks to maintain its management autonomy. - Mitsubishi Motors is reportedly opting out of the planned merger between Nissan and Honda. - Mitsubishi's decision is driven by concerns over maintaining management autonomy. - The merger between Nissan and Honda is still proceeding without Mitsubishi's involvement. - Mitsubishi's shares have plunged following reports of its decision. - Mitsubishi and the merged Nissan-Honda group may still maintain close cooperation.