The Fair Trade Commission determined Thursday that two semigovernmental research institutes have been rigging bids regularly since at least 1999, artificially inflating prices on 327 research contracts.

The bids, for contracts worth 3.18 billion yen in total, were for research projects on the market prices of construction materials in the Kanto region.

The two public-interest institutes are the Economic Research Association (Keizai Chosa Kai) and the Construction Research Institute (Kensetsu Bukka Chosakai). Both are based in Chuo Ward, Tokyo, and are affiliated with and under the supervision of the Land, Infrastructure and Transport Ministry.