Last month the firm was banned by the Hong Kong Securities and Futures Commission from participating in new issues until next spring because it helped companies to manipulate their share prices when they floated on the stock market.
The commission confirmed Mr Theodolou's resignation, reported last month in the Independent. He had been reprimanded for 'failing to exercise proper management, supervision and control over Standard Chartered Securities'.
In mitigation, it said he did not join the firm until April 1992 and was chief executive for only the latter half of the period investigated, July 1991 to March 1993.
The practices discovered were already well established by the time he joined. The commission said that, as chief executive officer, he must assume ultimate responsibility for regulatory compliance, but added that he had not been involved in wrongdoing.
The commission said Mr Theodoulou had co-operated with it and had voluntarily surrendered his dealer and investment adviser licences in Hong Kong. It has told him he cannot reapply until January 1995.
Mr Theodolou said through his solicitor: 'It is accepted by all parties that personally, I have never acted dishonestly, and I have co-operated with the (commission) and Standard Chartered Bank at all times. I accept that senior directors have a heavy burden of responsibility and should be ready to take the blame for any wrongdoings - including those they have no knowledge of.'Reuse content