今年夏天，韓國股市經歷了劇烈震盪。基準指數Kospi在上半年翻倍後，於七月底急劇下跌。這波漲跌的幕後推手是散戶大量購買槓桿型單一股票ETF，這類產品主要追蹤三星和SK海力士的表現，利用衍生品放大收益，使散戶能獲得以往無法取得的槓桿。當市場下挫時，ETF引發的劇烈波動觸發了大規模追繳保證金，加深了投資人的損失。

ETF原本是一種低風險的普通指數型工具，旨在讓散戶以極低成本投資多元化的股票組合。然而，投資公司如今正以更複雜的產品瞄準散戶，包括槓桿型單一股票ETF和反向ETF等。這些新型產品將更高風險注入散戶投資組合，許多投資人並未完全理解其運作方式。由於每日結算的機制，這類產品在長期持有時可能侵蝕波動較大股票的報酬。今年已有超過一千檔ETF上市，其中近四分之一為槓桿型單一股票基金，反映出投機性產品日益泛濫的趨勢。（關鍵數字：1,000）

韓國監管機構已針對國內市場的動盪推出新規定，要求單一標的基金持有人在購買前完成教育課程。文章呼籲其他國家應從韓國的經驗中汲取教訓，加強資訊揭露要求，提升金融素養教育，並將新型ETF中內建的槓桿納入審慎監管和壓力測試的範疇。高槓桿且散戶參與度高的市場，令人不安地聯想起歷史上的市場崩盤。

South Korea's stock market experienced dramatic turbulence this summer. The Kospi index doubled in the first half of the year before collapsing in late July, driven largely by widespread retail purchases of leveraged single-stock ETFs tracking Samsung and SK Hynix. These products use derivatives to amplify returns, and when the market fell, ETF-driven volatility triggered a wave of margin calls that compounded investor losses.

Originally designed as low-cost, diversified index-tracking instruments, ETFs have evolved into increasingly complex and speculative products. Investment firms now offer leveraged single-stock and inverse ETFs to retail investors, many of whom do not fully understand their mechanics. Due to daily settlement, these products can erode long-term returns on volatile stocks. Over 1,000 new ETFs launched this year alone, with nearly a quarter being leveraged single-stock funds—part of a broader trend that includes cryptocurrencies, prediction markets, and zero-day options resembling gambling more than investing.

South Korean regulators have responded by requiring mandatory education courses for buyers of single-name funds. The article urges other countries to learn from Korea's experience by strengthening disclosure requirements, improving financial literacy, and incorporating the leverage embedded in novel ETFs into prudential stress tests. A highly leveraged market with significant retail participation carries unsettling parallels to past financial crashes.