Insider trading is widespread in Asia, and almost always goes unpunished. Tycoons are revered. And tradition dictates a high level of respect for the elderly.
So it's with some surprise that Thailand is watching the downfall of one of its richest, oldest entrepreneurs. Securities regulators have come down hard on the man who runs Thailand's second-biggest airline, and largest hospital operator, with both stocks jolting lower.
Former surgeon Prasert Prasarttong-osoth, 85, is Thailand's eighth-richest man, according to the Forbes ranking, with a net worth of $3.1 billion. But he's now banned from holding any position at a public company in Thailand.
The self-made billionaire, known as "Dr. Prasert," has been forced to step down from his role as CEO and vice chairman of the boutique carrier Bangkok Airways. The Securities and Exchange Commission of Thailand found him to have manipulated the company's stock.
Besides the airline, Prasert has also stepped down from Bangkok Dusit Medical Services, the country's largest private-sector health-care provider, where he was president and group CEO.
Shares in Bangkok Airways fell 7.1% with word of the penalty, and remain subdued. Bangkok Dusit Medical Services slumped 8.5%.
According to the SEC, Prasert and one of his daughters, Poramaporn Prasarttong-osoth, as well as the executive secretary to the CEO's office, Narumon Chainaknan, manipulated the share price of Bangkok Airways by trading the stock among themselves.
This took place between Nov. 13, 2015, and Jan. 12, 2016, the stock watchdog says, with the trio executing trading transactions as a group, "on a continuing basis," while concealing their trading activities.
This, the regulator says, misled the public about the share price and real trading volume of the company's stock. The price and volume became "inconsistent" with normal market conditions, the regulator says.
The SEC has fined the trio a combined 499.45 million baht ($15.7 million). Each of the three is also now banned from being a director or executive of a listed company, or indeed any company that issues securities.
The sanctions mean they possess "untrustworthy characteristics" for directors or executives of public companies, according to the SEC. That requires them to step down.
The SEC says that if the three do not comply with its civil sanctions, the commission will refer the case to the public attorney and push for the "maximum civil penalty."
Bangkok Airways responded with a letter of "clarification" to the president of the Stock Exchange of Thailand. Prasert and his executive secretary "will pursue to prove their innocence in this matter through the justice system," the letter states.
But the pair have tendered their resignations as of Monday "in view of the good corporate governance principle."
The founder's hand won't be too far from the flight controls -- his eldest son, Puttipong Prasarttong-osoth, remains president of Bangkok Airways and was already running it day-to-day. Puttipong is untouched by the proceedings.
The Bangkok Airways board will meet on Thursday to discuss the case further. But it does not believe there will be a negative effect on the company's finances or operations.
Another letter with much the same wording says that Prasert and his daughter will defend themselves and "prove their innocence" through the justice system.
Bangkok Dusit Medical Services runs 43 hospitals in Thailand, as well as two in Cambodia. The tycoon still owns 18.5% of the company's stock, with daughter Poramaporn holding another 3.6% of the hospital company.
Poramaporn also owns 6.5% of Bangkok Airways, where her father holds a 10.6% stake. Other family members own 36.5% of the airline, giving the family a majority controlling share of 53.6%. Confusingly, Bangkok Airways also owns 5.9% of the hospital chain.
The hospital company's board met on Wednesday to take steps to replace the executives. The company named an acting president, Narumol Noi-Am. It named Puttipong, the son running Bangkok Airways, as substitute director at the health chain, in place of his sister.
After first working as a surgeon, Prasert began an aviation business in 1968 offering charter flights to the U.S. military. He and a group of doctors set up Bangkok Hospital, the medical group's first holding, in 1972. He's now expanded in multiple directions -- his media business carries the rights to air the Premier League soccer from England, which is very popular in Thailand.
Bangkok Airways launched passenger service in 1986, and built the airport on the resort island of Koh Samui, one of its most-popular destinations from Bangkok. It had a tough start, with challenges in gaining government permits to compete with flagship carrier Thai Airways -- but had the advantage in that its rival had no flights to Samui.
The airline now owns and operates not only the Samui airport but also the air operations in Sukhothai, near the ancient city of that name in central Thailand, and Trat, another holiday getaway near the Cambodian border.