Split into three by the dissolution of the zaibatsu — and reunified three years later (1953)

Divided from outside, reassembled by an outside threat

The break-up and the reunification are not two sides of one judgement. The three-way split of 1950 followed the Holding Company Liquidation Commission’s Noda Iwajiro losing his argument to the occupation authorities that Marunouchi ought to be developed under a single consistent method; Mitsubishi Estate had no say in it. The merger of 1953, by contrast, was decided by the company and the old Mitsubishi firms themselves, and its immediate trigger was the share raid of September 1952, which threatened to put all of the former Mitsubishi land and buildings into other hands. Assets divided from outside were, in the end, gathered back together by their owners because a threat arrived from outside.

Even so, the buyback was not within Mitsubishi Estate’s own power. Neither Yowa nor Kaito nor their parent had the money to recover the shares; eight companies of the old Mitsubishi group, Mitsubishi Bank foremost among them, pooled funds and put in several hundred million yen at more than ¥800 a share. The integrity of Marunouchi as an asset was preserved by the cohesion of the former zaibatsu, not by one company’s balance sheet. That a block-by-block redevelopment plan could be put forward six years later followed from the ownership having returned to a single hand.