Mitsubishi Aluminum's products were deemed safe.
Nissan Motor Co. revealed it conducted vehicle inspections that don't comply with Japanese regulations for nearly four decades; Subaru Corp. allowed uncertified workers to inspect vehicles before shipment; Kobe Steel Ltd. admitted to falsifying product quality data; Takata Corp. filed for bankruptcy earlier this year after revelations that its air bags injured automobile passengers rather than protecting them.
On Thursday, the Japanese company acknowledged that three of its subsidiaries had falsified specification data about their products, including copper and aluminium sold to major industries like aerospace, automobile and power generation. Affected products are used in Self-Defense Forces airplanes and ships.
The ongoing investigation by the companies has not yet uncovered any cases that raise the possibility of legal violations or safety issues, according to the statement. Shipments of the products worth ¥29.4 billion were made between April 2015 and September this year to a total of 229 firms, including 70 in the aerospace industry as well as seven automakers.
Mitsubishi Cable is believed to have supplied O-rings to hundreds of industrial manufacturers.
Officials of the Acquisition, Technology and Logistics Agency under the Defense Ministry said products including rubber seals that did not meet the requested specification had been installed within hydraulic components of SDF aircraft and ship engines. It said it found problems at Mitsubishi Shindoh going back to October 2016.
The firm said the impact of the quality scandal on its financial results "are now unknown". A third unit, Mitsubishi Aluminum Co.
As a result, the company said it is strengthening its quality control.
At 10.30 a.m., an hour and a half after the morning trading session started, shares of Mitsubishi Materials fell 345 points, down 8.44 per cent to 3,745 yen, reports Efe news.
The company will hold a press conference, possibly as early as Friday, to explain how it will deal with the issue.