KOSPI closes at 6,696.96 on August 24, 2026 — Samsung falls 8.7%

The KOSPI closed at 6,696.96 on Monday, August 24, 2026 — down 215.99 points, or 3.12 percent.

The KOSDAQ went the other way, closing at 813.33, up 1.42 percent.

That split is the story.

1. The numbers

The KOSDAQ's prior close is derived by subtracting the day's gain.

Two Korean boards moving in opposite directions by that much on the same session tells you what this was. Not a general exit from Korean assets — a problem concentrated in the large caps that dominate the main index. The KOSDAQ rose on strength in secondary-battery names.

2. Who sold, who caught it

The signs invert exactly between the two boards.

On the main board, foreigners and institutions together put roughly ₩4.97 trillion of stock on the market. Retail investors took ₩3.32 trillion of it.

Which raises the question readers ask every time this pattern appears: if individuals bought that much, why did the index fall?

Because an index is made of prices at which trades clear, not of who holds the shares afterwards. If sellers walk their offers down and buyers meet them at each lower step, turnover rises and the index falls. Net buying is a record of who absorbed the supply — not a measure of buying pressure.

This brief covered why these flow figures diverge between outlets in "What foreign net buying is — and why the same day's number differs by publication." August 24 was another case: retail net buying was printed as both ₩3.32tn and ₩3.8tn.

3. Samsung Electronics, down 8.7 percent

After the close on August 21, Samsung's board approved its 2026 shareholder-return programme. The reported size was 90 to 110 trillion won — roughly $65 to $80 billion, and by a wide margin the largest such commitment by a Korean company.

At the next regular session, the stock fell 8.7 percent.

The reason cited is what was missing.

For readers outside Korea, the distinction matters more here than it might elsewhere. Korean investors have spent years pressing large family-controlled groups to return capital, and share cancellation — permanently retiring stock so each remaining share represents a larger claim — has become the test of whether a company means it. A dividend hands out cash once. A cancellation changes the arithmetic of ownership permanently.

Samsung named the largest number and left the mechanism open.

This brief covered the structure in "Samsung's 100-trillion-won payout — why it is dividends and not cancellations, and why the answer is a 10 percent stake" and in "What a share cancellation is."

The announcement came three days earlier. The market's answer came on August 24.

4. What else was in the background

Two more pressures sat on the market that day.

• US Treasury yields. The 30-year hit 5.31 percent on August 17, its highest since 2007. High long-end yields tend to pull foreign money out of emerging-market equities and into bonds.
• Tariffs. US tariffs of 50 percent on Canadian goods took effect August 22, with Canadian retaliation set for September 8. Korean firms are not the direct target, but North American supply chains transmit the effect upstream.

Neither can be assigned a point value. And the fact that the KOSDAQ rose the same day argues that this was not a general repricing of Korean risk.

5. What we could not confirm

• Flow discrepancy — retail net buying is reported as both ₩3.32tn and ₩3.8tn, without consistent labelling of which board is covered.
• Samsung's index contribution — not calculated by this brief.
• SK Hynix's close — not cross-checked, so left out.
• The won-dollar rate — not confirmed against two sources.
• What to watch next — when Samsung specifies the size and schedule of buybacks and cancellations. That gap is what the market punished; how the stock reacts when it is filled is the real verdict on this announcement.