Regent Pacific launched a scathing attack on Pioneer Industries' management yesterday for failing to disclose a significant shareholding in Bangkok Bank that amounted to 51 per cent of its net asset value. Peter Everington, the chairman of Regent, which holds 20 per cent of Pioneer, said that on top of the published 3.77 per cent stake in Bangkok Bank, Pioneer owned about another 6.5 million 'foreign' shares in it. He said the total shareholding in Bangkok Bank, one of Thailand's bigger banks, should be listed at about 4.5 per cent. 'Regent believes that the majority of shareholders do not know that the company owns these shares since neither the annual report for 1994-95 nor the annual report for 1995-96 provide any details about the holding of these shares,' he said. The undisclosed stake was held through a 49 per cent stake in a Liberian company, called Central Asia, which owned 13 million 'foreign' shares in Bangkok Bank. The rest of the stake in Central Asia was 50 per cent owned by the chairman of Bangkok Bank, Prasit Kanchanawat, and the remaining 1 per cent by Pioneer chairman Anthony Gaw. Regent corporate finance director Ascanio Martinotti said: 'This information was related to us by Mr Gaw.' Regent was convinced that Pioneer, through Central Asia, had been and was writing call options on a substantial part of the 'hidden' stake, an activity which the broking community had known about for some time, Mr Everington said. 'How can you write options on something you don't have control [over]?' he said. Regent demanded more disclosure about the additional stake, saying it was too significant to be ignored in the annual report. The market value of Pioneer's stake in Central Asia was about $616 million on Wednesday, equal to 51 per cent of Pioneer's net asset value of $1.2 billion, or 27 per cent of its market capitalisation. Regent raised concerns about the management's ability to 'grow or even preserve shareholders' equity'. It accused Pioneer of making poor investments, such as its stake in Wah Kwong Shipping, and property projects in Shanghai and the US. The relationship between Regent and Pioneer turned sour when Regent requisitioned an extraordinary general meeting for this coming Tuesday. Directors will be asked to narrow the discount between the market price and the net asset value, standing at about 50 per cent. Mr Everington stressed selling Bangkok Bank shares would be the last resort. To gain leverage on the Bangkok Bank shares, Pioneer can improve current income by the creation of various derivative instruments over the shares and skilful treasury management.