Utilize the input text as a context reference, choose the right relationship between lead and Japan from the options. Options: product/material produced, manufacturer, distributed by, industry, position held, original broadcaster, owned by, founded by, distribution format, headquarters location, stock exchange, currency, parent organization, chief executive officer, director/manager, owner of, operator, member of, employer, chairperson, platform, subsidiary, legal form, publisher, developer, brand, business division, location of formation, creator.

The firm is one of the lead underwriters of initial share sales by state-owned Japan Post Holdings Co. and its banking and insurance units scheduled for later this year.

Answer: location_of_formation