Samsung Electronics and SK Hynix together accounted for 6.9669 trillion won of South Korea’s stock credit loan balances as of 12 November, 27.2% of the 25.5976 trillion won total across the Kospi and Kosdaq markets, SBS News reported, citing financial information provider FnGuide.
Last year the two stocks accounted for an average of 6.73% of the total credit loan balance, Chosun Ilbo reported. By our arithmetic, their share is now about 4.0x that average.
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The key insight: As we read the FnGuide figures, borrowed money in Korea’s stock market has become a chipmaker trade: two stocks hold 27.2% of the balance against a 6.73% average last year, SBS News and Chosun Ilbo reported.
Samsung Electronics’ credit loan balance stood at 3.6358 trillion won and SK Hynix’s at 3.3311 trillion won as of 12 November, Chosun Ilbo reported. On the Kospi market alone, the two stocks made up 36.5% of the 19.0935 trillion won total, it said.
Credit loan balances are the amounts investors have yet to repay after borrowing from securities firms to buy stocks, Chosun Ilbo explained. By our arithmetic, Samsung accounts for about 52% of the two-stock total and SK Hynix about 48%.
Samsung Electronics and SK Hynix share of South Korean stock credit loan balances; FnGuide data via SBS News and Chosun Ilbo, 12 November 2026.
Below the July Levels
The combined balance stood at 10.7596 trillion won as of 8 July, the Hankyung report carried by Bloomingbit said, citing the financial investment industry. By our arithmetic, the 12 November figure is about 35% lower, though the two counts come from different data providers.
Samsung’s credit balance reached 5.5353 trillion won on 9 July, JoongAng Ilbo reported, citing Yonhap Infomax, after starting the year at about 1.7197 trillion won. By our arithmetic, the 12 November figure is about 34% below that July level and about 2.1x the start of the year, again across different data providers.
Collateral Rules Eased
The Financial Supervisory Service announced on 9 November that it would temporarily suspend, until 31 January, the obligation for securities firms to keep a collateral ratio of 140% or higher on credit loans, Chosun Ilbo reported. Securities firms have responded by lowering the ratio to 130% or delaying forced sales by one day for same-day applicants, it said.
As we read the July comparisons, the concentration rose even as the amount fell: the two-stock balance is about 35% below the 10.7596 trillion won of 8 July in the Hankyung report, by our arithmetic, across different data providers.
As we read the regulator’s move, the Financial Supervisory Service eased the 140% collateral obligation until 31 January as volatility grew, Chosun Ilbo reported, which defers forced sales rather than removing the loans.
Chosun Ilbo, 15 November 2026
“While debt-fueled investments can fuel upward momentum during rising stock prices, they also risk exacerbating declines through cascading liquidations when prices fall”
Three Implications
FOR THE TWO CHIPMAKERS Samsung Electronics held 3.6358 trillion won and SK Hynix 3.3311 trillion won of credit loan balances as of 12 November, Chosun Ilbo reported.
FOR THE KOSPI The two stocks made up 36.5% of the 19.0935 trillion won Kospi total, Chosun Ilbo reported.
FOR SECURITIES FIRMS Firms have lowered the collateral ratio to 130% or delayed forced sales by one day for same-day applicants, Chosun Ilbo reported.
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What Is Not Established
The July and 12 November figures come from different providers (industry data cited by Hankyung, Yonhap Infomax and FnGuide), so the comparisons are approximate. The reports do not say how many investors hold the loans or how much of the balance sits in leveraged single-stock products. Chosun Ilbo and SBS describe the market impact of the concentration as what observers suggest, not a measured effect.
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Samsung Electronics and SK Hynix accounted for 6.9669 trillion won, or 27.2%, of South Korea’s credit loan balances as of 12 November, against a 6.73% average last year, FnGuide data reported by SBS News and Chosun Ilbo show.
A note on sourcing. Figures come from FnGuide data as reported by Chosun Ilbo English and SBS News (15 November 2026), with July and start-of-year comparisons from the Hankyung report carried by Bloomingbit (9 July) and JoongAng Ilbo citing Yonhap Infomax (16 August), read on 15 November 2026; the Korean-language reports were translated by us. Ratios are our arithmetic, and comparisons across data providers are approximate.
Gennaro Cuofano is a CRO and tech executive who has worked in AI since late 2015, starting with bringing NLP, natural-language generation, voice and chatbot products to the marketing industry. His background is in law and finance: he holds a Master's degree in Law and an International MBA with an emphasis on corporate finance (LUISS Business School and the University of San Diego, 2012), and worked as a financial analyst at a real-estate investment firm in San Diego and as an assistant controller. His work focuses on business model strategy, business engineering and, more broadly, structural analysis: how companies make money, read from their own filings. He created FourWeekMBA and leads research there and at The Business Engineer, his newsletter on AI and business strategy, with over 95,000 subscribers and more than 1,000 published analyses. His writing has also appeared on Entrepreneur (for example, How to Digitize a Family Business in Europe) and HackerNoon. Find him on LinkedIn and Substack. See how we source.
