The U.S. International Trade Commission issued a preliminary ruling Thursday charging that stainless steel angles imported from Japan are hurting the U.S. industry.

All six ITC commissioners ruled in favor of Indiana-based Slater Steel Inc. and the United Steelworkers of America labor union, which in August jointly filed the antidumping complaint against the Japanese imports with the ITC, an independent U.S. federal agency, and the Commerce Department.

The Commerce Department is expected to release a preliminary ruling on the case in January.

Among the Japanese companies cited in the complaint are Aichi Steel Corp. and Daido Steel Co.