Japan Exchange Group Inc. has decided to scrap a plan to adopt tougher disclosure rules, saying the nation's companies are getting better at communicating with investors on their own.

The exchange will seek clearer comments on an individual basis and keep track of companies' responses, according to Taisuke Maruo, a senior manager in the listing department at the Tokyo Stock Exchange, JPX's cash equities trading venue. The TSE had said in July it was looking to come up with new rules by the end of 2013, after Kawasaki Heavy Industries Ltd. issued conflicting statements on merger talks with a competitor.

"We've been asking listed companies to disclose more on important matters when we consider it necessary," Maruo said in an April 4 interview. The TSE is satisfied with the improvement seen since the middle of last year and companies have received "passing marks" on almost all of their important disclosures, he said.