The Securities and Exchange Commission (SEC) says it is investigating filing documentation for share purchases in six Thai companies since 2021 by a mystery investor who last week reported acquiring a 7% stake worth 32 billion baht in True Corporation.
The regulator said the purchases of shares in the companies listed on the Stock Exchange of Thailand were made between 2021 and 2025 by an investor it named as Supaporn Pimphong.
Ms Supaporn’s stake in True has since dropped to 3.69%, which makes her the telecom company’s sixth-largest shareholder, according to LSEG data.
The SEC said the Form 246-2 shareholding disclosures submitted by Ms Supaporn were found to be inconsistent with shareholder records.
The case has attracted widespread attention from market observers who have raised concerns about the self-declaration disclosure system, which allows investors to report significant share acquisitions before regulators verify the information.
The discrepancies have given rise to speculation that the reporting system itself could have been compromised, hacked or somehow manipulated by parties linked to “grey money”.
Under Thai law, investors holding 5% or more of a company’s shares must officially report their holdings.
SEC officials said they had determined that Ms Supaporn is a real person who had completed identity verification through the regulator’s electronic filing system using Thailand’s national civil registration database.
However, the mystery investor appears to have a very low public profile and no online presence to speak of.
Regulators confirmed that she personally submitted the reports but said the accuracy of the disclosed shareholdings remains under investigation.
The filings claimed holdings of 9.99% in Major Cineplex Group (MAJOR), 7.09% in True Corporation (TRUE), 5.1% in Kasikornbank (KBANK), 5.01% in Bangkok Bank (BBL), 5.33% in Asia Aviation (AAV), and two separate filings for GJ Steel (GJS) reporting stakes of 80.9% and 48.6%, with one filing stating that the shares were inherited.
The SEC said its preliminary review found that Ms Supaporn’s name does not appear on the shareholder registers for five of the six companies under review, while one case remains under examination.
In addition, some filings referred to securities that companies said had never been issued, while other holdings were inconsistent with corporate disclosures.
True told the SET that Ms Supaporn’s filing referred to some preferred shares that did not exist.
“The information contained in filings is preliminary information only, which means that the information in the report remains incomplete and/or is under review,” True said in a statement on Monday.
SEC deputy secretary-general Anek Yooyuen said that if any actions are found not to comply with the law or relevant regulations, the SEC will consider taking strict legal action accordingly.
