Haseko Corporation is a Japanese construction company specialized in construction of condominium units. From 1968 to 2015, the company built a total of around 580,000 condominium units, which is approximately 10% of the total number of condominium units on the market in Japan. The company is highly vertically integrated, with all of the lifecycle of condominium construction and maintenance handled by the company or its subsidiaries. On October 1, 2015, Haseko Corporation was included in the Nikkei 225 stock market index. Wikipedia