Three state-affiliated companies in the Japan Post Group are set to go public on the Tokyo Stock Exchange on Nov. 4 in the nation's biggest initial offering — with the government seeking to raise ¥1.4 trillion in the first phase of the sale.

The three giants are expected to have a combined market capitalization of over ¥12 trillion when listed.

The listing of Japan Post Holdings Co., the holding company for the group, and of financial subsidiaries Japan Post Bank Co. and Japan Post, is significant in a number of ways, with much at stake.