Contractor Takenaka Corp. is suspected of concealing some ¥150 million in taxable income over a four-year period through December 2013, sources familiar with the matter said Monday.
The Osaka-based builder intentionally reduced its profit numbers by padding orders for building materials, such as reinforcing steel.
Takenaka, one of the nation's five major contractors, also failed to declare some ¥450 million in taxable income via bookkeeping mistakes and thus was slapped with some ¥500 million in back taxes, the sources said.
Investigators from the National Tax Agency looked into Takenaka's accounting reports and determined it concealed taxable income on purpose, they said.
Takenaka, which is not a publicly listed company, declined to comment on the matter.
The contractor's group sales reached about ¥1.15 trillion in the business year ended in December 2014.