Japan Post sued Seibu Railway Co. and two other parties Tuesday, demanding 3.67 billion yen in damages for the investment loss it incurred due to the 2004 delisting of Seibu Railway following fabrications of its financial statements.

The two other parties are Seibu Railway's former parent Kokudo Corp. and Yoshiaki Tsutsumi, the one-time effective owner of the Seibu group.

Filing the suit with the Tokyo District Court, Japan Post demanded that the three compensate the loss that the public postal services company suffered as a result of a dive in the price of Seibu Railway shares in fall 2004.