Hong Kong's first criminal trial for insider trading has resulted in the conviction of a former investment banker and four other defendants.

Ma Hon Yeung, a former vice president at BNP Paribas Peregrine Capital, passed confidential information to his girlfriend and three family members about the proposed privatisation of Egana Jewellry & Pearls, a matter on which he was working. The four tippees all traded in Egana shares before the company announced its privatisation plans in July 2006.

The five defendants will be sentenced on 1 April.

The case, which was heard in Hong Kong District Court, was brought by the Securities and Futures Commission (SFC) under the 2003 law that for the first time made insider trading a crime. Insider trading was previously considered a civil offence and was rarely punished. The crime now carries a 10-year maximum prison term.

"This case, being the first indictable trial for insider dealing, is a landmark decision," said Mark Steward, the SFC's enforcement director, in the statement announcing the convictions.

A spokesman for the SFC said the agency would not be disclosing the amount Ma and his fellow defendants illegally profited.

The SFC has a number of other prosecutions pending, the most high-profile of which is that of former Morgan Stanley investment banker Du Jun.

Du, a former managing director with Morgan Stanley's China group, was arrested last year for allegedly buying shares of CITIC Resources Holdings worth HK$86m (£8m) just prior to the announcement of an oilfield acquisition by CITIC on which Du and Morgan Stanley had advised.

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