Foreign residents in Japan with securities accounts should be on high alert following the arrest of two individuals involved in a sophisticated account hijacking scheme that manipulated stock prices and defrauded investors of approximately 100 million yen. According to NHK, Japanese authorities arrested a Chinese national company president and an accomplice in late November 2025 for hijacking other people's securities accounts and manipulating stock prices through coordinated trading. The scheme involved taking control of legitimate accounts, artificially inflating stock prices through repeated buy-and-sell transactions, and then selling off shares at the elevated prices for profit. The investigation revealed that the perpetrators began unauthorized access to compromised accounts more than ten days before executing their trades, according to NHK reporting. During this reconnaissance period, they carefully examined account balances, holdings, and available funds to plan their manipulation strategy. This preliminary surveillance allowed them to identify suitable accounts with sufficient assets to execute their scheme. The suspects specifically targeted "low-priced stocks" (teii kabu), which are shares trading at relatively low values that are particularly susceptible to price manipulation. Because these stocks have lower trading volumes and market capitalization, even modest trading activity can create significant price movements. By using hijacked accounts to repeatedly buy and sell these volatile securities within short timeframes, the perpetrators artificially drove up prices before liquidating their positions at the inflated values. Investigators believe the two suspects raised approximately 100 million yen through their activities, according to NHK. This substantial sum was generated not only through the pump-and-dump manipulation scheme but also by selling off stocks and other assets held in the compromised accounts. The victims likely remained unaware of the unauthorized activity until they received notifications of trades they never authorized or noticed unexplained changes in their portfolio holdings. This case highlights critical vulnerabilities in securities account security that affect all investors in Japan, including foreign residents. Unlike bank accounts, which typically have more robust fraud detection systems and immediate transaction alerts, securities accounts may not always provide real-time notifications for every trade. This delayed awareness can give criminals a window of opportunity to execute complex manipulation schemes. For expats maintaining investment accounts in Japan, this incident underscores several important security considerations. First, language barriers can make it more difficult to notice suspicious activity if account statements and alerts arrive only in Japanese. Foreign residents should ensure they understand how to access and interpret their account activity, even if this requires assistance from bilingual financial advisors or translation services. Second, many expats may maintain securities accounts through online brokerages that offer English-language interfaces, but security settings and two-factor authentication options may still require navigation through Japanese-language menus. Taking time to properly configure security features, including strong passwords and multi-factor authentication, is essential. The investigation into how the perpetrators initially gained access to the accounts remains ongoing. Common methods for account compromise include phishing attacks, malware, data breaches at third-party services, and credential stuffing attacks using passwords stolen from other platforms. Foreign residents should be particularly cautious about emails or messages claiming to be from financial institutions, especially if they contain urgent requests or links to login pages. Japanese financial authorities and securities firms are likely to enhance security measures in response to this case. Investors should proactively contact their brokerages to inquire about available security features, transaction notification options, and procedures for reporting suspicious activity. Regular monitoring of account statements and trade confirmations remains the most effective defense against unauthorized access. This case serves as a reminder that investment fraud can take sophisticated forms beyond traditional scams, and that all residents of Japan, regardless of nationality, should maintain vigilant oversight of their financial accounts.