Uracha Wachirakun-thon was suspended for 10 years following the transfer of a significant number of shares to an account owned by her mother.
The other two were suspended 6 months and 1 month, respectively.
Two AEC executives were also suspended for six months for failure to impose oversight in the company's oprerations. The company is also fined for Bt1.1 million.
In the statement, the SEC did not specify the name of Chuwong who died on June 27 in what Pol Lt-Colonel Banyin Tangpakorn, a former deputy commerce minister and MP, claims was a car accident.