The Tokyo Stock Exchange has slapped a fine of 200 million yen (£1.5 million) against Nomura Securities as a penalty for an insider trading scandal in which top executives resigned at the Japanese brokerage.
The fine was the highest ever by the exchange and represents the latest action calling for better controls at Japan's biggest brokerage.
Nomura chief executive Kenichi Watanabe resigned earlier this year to take responsibility for the scandal in which information was leaked ahead of securities offerings.
Nomura has acknowledged that some employees were involved and has promised to take steps to prevent recurrences, such as reviewing internal rules and practices.
Under Japanese law, leaking inside information is not penalised as heavily as profiting from insider trading, although some are advocating that the law be revised.