Vietnam fines individual 1.5B VND for manipulating MTG stock over 19 months

Overview

The State Securities Commission (SSC) has fined Phạm Thị Mỹ Diệu 1.5 billion VND and revoked her securities license for manipulating the stock of MT Gas (MTG) over a 19-month period. The penalty, announced on August 28, also includes a three-year trading ban and a ban on holding positions at securities firms. The case highlights ongoing regulatory enforcement against market manipulation in Vietnam’s smaller-cap stocks.

Key Facts

• Phạm Thị Mỹ Diệu was fined 1.5 billion VND (approximately USD 60,000) for manipulating MTG stock.
• Her securities license was revoked for 21 months, and she is banned from trading and holding management roles in securities companies for three years.
• The manipulation occurred from October 31, 2022, to May 31, 2024, using two trading accounts.
• Trần Xuân Dũng, who lent his account to Diệu, was suspended from trading for 9 months and banned from trading and management roles for two years.
• MTG’s stock price rose from 3,800 VND on October 31, 2022, to a peak of 15,300 VND on March 25, 2024, a fourfold increase.
• Market capitalization of MT Gas increased from 23.9 billion VND to 159.9 billion VND during the period, partly due to a private placement in February 2024 that raised nearly 50 billion VND.
• The SSC found no illegal profits from the violation for either Diệu or Dũng.

What Happened

The SSC issued administrative penalties against Phạm Thị Mỹ Diệu for manipulating shares of MT Gas (MTG), a company listed on the UPCOM exchange. According to the SSC’s decisions, Diệu used two securities accounts to continuously buy and sell MTG shares from October 31, 2022, to May 31, 2024, creating artificial supply and demand. The regulator’s investigation found no illegal profits from the activity, but the actions were deemed manipulative.

Trần Xuân Dũng, who lent his account to Diệu, also faced penalties: a 9-month suspension of trading activity, a two-year ban on trading, and a two-year ban on holding positions at securities business organizations. Both sets of penalties took effect on August 28. The SSC stated that there was no basis to determine that Dũng derived illegal benefits from the violation.

Market Context

MTG shares on UPCOM have been thinly traded recently. During the 19-month violation period, average daily volume was about 6,000 shares. Since the start of 2026, out of 161 trading sessions, MTG had no liquidity in 130 sessions. The stock has been trading sideways around 10,000 VND, closing at that level on July 30, 2026. The manipulation case adds to the regulatory overhang for a stock that already suffers from low liquidity and small market cap.

Strategic Significance

This enforcement action signals the SSC’s continued vigilance against market manipulation, particularly in small-cap and UPCOM-listed stocks where liquidity is thin and price movements can be easily influenced. For MTG, the penalties may further dampen investor confidence, though the absence of illegal profits and the passage of time since the violation could limit long-term impact. The case also underscores the risks of lending accounts and engaging in coordinated trading, which can lead to severe personal penalties.

What to Watch

• Any further regulatory actions or investigations involving MTG or its related parties.
• Changes in MTG’s trading liquidity and price stability in the coming months.
• The company’s operational and financial performance, especially after its private placement in early 2024.
• Potential improvements in corporate governance or investor relations to restore market confidence.
• SSC’s broader enforcement trends on market manipulation cases in 2026.