Nihon Keizai Shimbun Inc. President Ryoki Sugita said Friday its managing director in charge of advertising, Takashi Kageyama, resigned the same day to take responsibility for alleged insider trading by an employee at the business daily's advertising department.

President Sugita told a news conference he and two other executives also will take a three-month pay cut over the incident, after the firm conducted a preliminary investigation into the allegation.

The Securities and Exchange Surveillance Commission has launched its own investigation into the matter.