tsutsumi registered seibu railway shares owned by kokudo in the names of various affiliated individuals, often without their permission, so that the true ownership of the company was not readily apparent. following the death of tsutsumi in 1964, his third son yoshiaki tsutsumi inherited control of kokudo and continued the practice of falsifying shareholder records. his holdings in kokudo and seibu led to his being deemed the "world's richest man" by "forbes" magazine for four consecutive years from 1987 to 1990, with estimated net worth of $15–20 billion during the height of the japanese asset bubble. he was arrested on securities fraud charges in march 2005.