THE first Insider Dealing Tribunal hearing to be held under laws passed in 1991 opened yesterday before Mr Justice Stock with a preliminary hearing of the inquiry into the trading of Success Holdings. Last year, Success Holdings was renamed Walsin Hong Kong Corp after being taken over by Walsin. In a separate development, Angkasa Marketing (Singapore), a wholly owned subsidiary of Malaysian-based Amalgamated Steel Mills, said yesterday it was beneficially interested in 206.6 million shares in Walsin, representing about 98.34 per cent of its issued share capital, following an offer that closed on April 22. Walsin had requested the Stock Exchange to suspend dealings in its shares pending an announcement. Angkasa and Walsin have undertaken to ensure that at least 25 per cent of the issued share capital of Walsin will be held by the public as soon as possible. Mr Justice Stock, sitting with members Patrick Yeung and Derek Murphy, pointed out that the role of the tribunal was inquisitive and anyone implicated in any matter was entitled to be represented by a lawyer. The inquiry, which will start next Monday, follows an investigation by the Securities and Futures Commission (SFC) into the trading of Success Holdings between May 15 and June 12, 1992. After a report was compiled, it was handed over to Financial Secretary Sir Hamish Macleod who passed the case on to the tribunal. It was the first case to be referred by Sir Hamish under the provisions of the Securities (Insider Dealing) Ordinance of 1991. Mr Justice Stock said the tribunal would look into the trading of Success Holdings' shares around the time of the three important events concerning the investigation. They were: the announcement of the privatisation of Success; the proposal to pay 12 cents per share to all the shareholders; and the takeover of Success Holdings by a third party and a conditional cash offer. During yesterday's short hearing, Mr Justice Stock also outlined the tribunal's jurisdiction and procedures. Counsel for the tribunal is Joseph Pethes. Ronny Wong QC and Wilson Chan will represent Lau Hon-chung and Timothy Bellis will represent Francis Leung Pak-to. The last person named in connection with insider trading was Clifford Pang Lun-kee, the former chairman of Lafe Holdings, in 1986. Mr Pang was found culpable of insider trading ''to a very high degree'' after being found to have sold his 40 per cent stake in Lafe Holdings when he knew it was going to report a large loss. Cheung Kong (Holdings) chairman Li Ka-shing was named in a tribunal in 1986.