What about Renault and Mitsubishi?
Renault saved Nissan in 1999. And Nissan saved Mitsubishi in 2016. What happens to Renault and Mitsubishi if Honda and Nissan merge? Are they left alone and out of the merger, perhaps left to find other saviours?
Renault and Nissan (and lately Mitsubishi) are in an alliance, sharing platforms, technologies and even a CEO (Carlos Ghosn). This alliance (and Mr. Ghosn) is credited with having saved Nissan in 1999; Renault and Nissan traded shares but remained independent.
Nissan bought just over a third of Mitsubishi's shares in 2016, saving Mitsubishi. In Japan, owning one-third of shares is enough to attain and maintain control of a company; it is how Ford was able to keep Mazda afloat for so many years without owning a majority proportion of shares. Nissan a subsequently sold some of those shares, likely losing control of Mitsubishi.
In the earlier news of this agreement to study a merger, I saw nothing about Mitsubishi but later news items include Mitsubishi.
Curiously absent from the joint press releases are Renault and Mitsubishi. Both companies formed a strategic partnership with Nissan way back in 1999, and Renault is presently Nissan's main shareholder. In a very brief announcement, Renault Group acknowledged the new MOU and stated it would "consider all options based on the best interest of the Group and its stakeholders."
Mitsubishi is considerably more involved. The company announced it had also signed a MOU with Nissan and Honda, but only to "explore the possibility of Mitsubishi Motors' participation, involvement, and synergy sharing" in this new holding company. A decision should come by late January 2025. In November, Nissan announced it was selling one-third of its stake in Mitsubishi.