Kozo Iwata岩田弘三

Major shareholder of Rock Field Co.,Ltd.

Net worth (est.)

¥4.0B

#812 in Japan

Listed shares · incl. ¥3.0B via asset-management cos.

Executive pay

—

Not disclosed

Dividends (a year)

¥74.0M

#975

Own name ¥18.8M / via companies ¥55.2M

Total income (est.)

¥74.0M

#1929

Pay + dividends, before tax

Taxes (est.)

¥4.5M

#4335

Income tax ¥3.1M / resident tax ¥1.4M

Other assets (est.)

¥58.5M

¥4.1B with shares

After-tax income 2026, before spending

Other assets (est.): the sum of each year's after-tax income (pay + dividends in own name − estimated taxes and social insurance) and dividends retained by asset-management companies (less about 20% corporate tax), for the years we have data. Spending, real estate, donations and savings from earlier years are not reflected.

Asset-management companies: Iwata Co., Ltd.est. (their holdings are included in net worth)

Holdings

Company	Held by	Shares	Stake	Price	Value	Dividends
Rock Field Co.,Ltd. 2910 · FY ending Apr 2026	Iwata Co., Ltd.	2,300,000	8.80%	¥1,298	¥3.0B	¥55.2M
Rock Field Co.,Ltd. 2910 · FY ending Apr 2026	Own name	784,000	3.00%	¥1,298	¥1.0B	¥18.8M

Estimates from annual securities reports (EDINET). The English name is romanized automatically and may differ from the spelling the person uses. Methodology · Corrections and removal requests: contact

Kozo Iwata岩田 弘三

Holdings

Kozo Iwata岩田弘三