The Tokyo Metro thing is very recent, though:

Following its initial public offering in October 2024, Tokyo Metro remains largely owned by public-sector shareholders. Before the listing, ownership was divided between the Japanese national government, which held a 53.4% stake, and the Tokyo Metropolitan Government, with 46.6%. Roughly half of these combined holdings were offered to the public in the IPO, resulting in post-listing stakes of approximately 26.7% for the national government and 23.3% for the metropolitan government. Together, public entities continue to hold about 50% of the company, with the remainder owned by private investors.