Obayashi Corporation is one of five major Japanese construction companies along with Shimizu Corporation, Takenaka Corporation, Kajima Corporation, and Taisei Corporation. It is listed on the Tokyo Stock Exchange and is one of the Nikkei 225 corporations. Its headquarters are in Minato, Tokyo. In 2018, Obayashi was ranked 15th place on ENR's list of Top 250 Global Contractors, the highest rank among Japanese Contractors.

Taisei Corporation is a Japanese corporation founded in 1873. Its main areas of business are building construction, civil engineering, and real estate development. Taisei's headquarters are located at Shinjuku Center Building in Nishi-Shinjuku, Shinjuku, Tokyo.