The nation's securities watchdog filed a complaint April 8 with the Nagoya District Prosecutor's Office against four men, including the former chairman of top women's wear retailer Suzutan Co., on suspicion of insider trading.

Katsurao Suzui sold roughly 1.3 million Suzutan shares that were in his possession or held by a firm set up to manage his assets from around May 1994, prior to an announcement of poor performance at a Suzutan subsidiary that was certain to hurt the retailer, investigations by the Securities and Exchange Surveillance Commission have revealed. Nearly 1.6 billion yen was made through these sales, according to sources close to the investigation.

The commission considers these transactions to be insider deals that are currently banned under the Securities and Exchange Law. Such illicit deals carry a penalty of up to six months in prison or a maximum fine of 500,000 yen.

Complaints were also filed against Suzui's son and former Suzutan President Shigemitsu, Shuzo Hirao, a former managing director of Suzutan, and Goro Kato, auditor for Suzui's asset management firm Suzui Kosan, and Suzui Kosan itself. The price of Suzutan shares peaked at 1,500 yen in early October 1994, but plunged in the weeks following the mid-October announcement of the outstanding debts of the subsidiary.

The case is the ninth in which the securities watchdog, formed in 1992, has filed a complaint with prosecutors and the fourth in which insider trading was alleged.