The Fair Trade Commission on Tuesday searched the offices of major general contractors Kajima Corp., Shimizu Corp., Taisei Corp., Obayashi Corp. and Penta-Ocean Construction Co. in connection with suspected bid-rigging for public works projects in the city of Niigata.
The FTC said the searches targeted the local offices of the big construction companies as well as small local contractors and a Niigata association of construction firms. The number of companies searched came to about 40, it said.
Kajima and Taisei said they were aware of the FTC investigation but declined to comment on it.
According to investigative sources, the companies held talks before tenders were opened for civil engineering projects by the Niigata Municipal Government to determine which company should be awarded the contract and for how much.
The city orders more than 10 billion yen worth of civil engineering works each year.
Despite several attempts in the past, the antimonopoly watchdog has so far failed to establish a criminal bid-rigging case against major construction firms due largely to the difficulty in obtaining physical evidence.
In June, the FTC issued warnings to 29 large construction companies over suspected bid-rigging.