All companies and people working in capital markets must cooperate in acting against corruption, SEC secretary-general Vorapol Socatiyanurak said in a letter released on Friday.
Mr Vorapol said corruption was a chronic problem that had had a huge impact on Thailand for a long time. Action to overcome this problem would require cooperation from everyone. They need to oppose, reject and provide no support at all to people whose behaviour is corrupt, he wrote.
He made specific mention of the case involving Rai Som Company and Sorayuth Suthassanachinda, who stand accused by the National Anti-Corruption Commission (NACC) of bilking the state majority-owned broadcaster MCOT out of 138 million baht six years ago.
Mr Sorayuth has refused calls from media groups and others to step aside from his current positions at television Channel 3, where his programmes are among the station's biggest money-makers, until his case is resolved.
BEC World, the SET-listed operator of Channel 3, has had no comment on the Sorayuth case. The Anti-Corruption Network, whose members include some of the country's biggest businesses, is encouraging its members to withdraw their commercials from Channel 3 until there is a satisfactory response.
Mr Vorapol's letter noted that in the Rai Som case, the NACC on Sept 20 had found the company and its front man guilty of supporting officials, in this case MCOT employees, committing offences under the Offences Committed by Officials of State Organisations or Agencies Act B.E. 2502 (1959) and the Criminal Code. They were accused of under-reporting advertising time sold for programmes produced by Rai Som for Modernine television.
On Oct 4, 2012, the Press Council of Thailand issued a statement indicating that the acts alleged to have involved Rai Som were a violation of the profession's code of conduct even though there was no final legal conclusion.
"The SEC office would like to ask for thorough consideration and caution in having business dealings with persons with corrupt behaviour, in order to jointly solve the corruption problem in the country," said the letter.
It was sent to the managing directors of all listed companies, securities firms, financial advice firms and related associations in the capital market.
An industry source said it was the first time that the SEC had issued such a letter pinpointing a particular name.
The letter also mentioned a survey by Assumption University, or Abac Poll, which revealed that 68.5% of respondents would accept "some corruption" if they also benefit from it.
The letter said that if people insisted on remaining ignorant because they are more worried about losing some benefits, the country will never be able to solve the problem.
The SEC chief said organisations linked to the capital market had continuously helped to improve corporate governance, so that Thailand now ranks the third in the Asia Pacific area in the CG Watch 2012, prepared by the Asian Corporate Governance Association and CLSA Asia-Pacific Markets.