This week in review
A window on where the market moved over the week
KOSPI closes Friday at 6,912.95, down 0.93% on the week — a four-session arc of crash, rebound, and bifurcation
KOSPI Swings 12.75% Peak-to-Trough in Four Sessions as U.S. Treasury Rates Whipsaw the Market
The week opened Tuesday with a 1.55% decline before Wednesday delivered a 5.80% collapse — the session’s headline pinned the move on a SOX shock that exceeded modeled ranges, compounded by surging U.S. Treasury yields.Thursday reversed sharply, with the KOSPI rallying 5.89% after the U.S. Treasury signaled a liquidity backstop and yields retreated, recovering the 6,852 level within a single session.Friday produced a split verdict: the KOSPI added 0.88% while the KOSDAQ fell 4.63%, leaving the KOSPI down 0.93% for the week and the KOSDAQ off 7.25% — its weekly return ranking 31st out of 33 weeks in the 2026 year-to-date sample.
The week in numbers
A window measuring the week’s change, its range and where it sits within the year
KOSPI ends the week at 6,912.95 (−0.93%); KOSDAQ at 801.94 (−7.25%) — both close in negative territory
| Item | KOSPI | KOSDAQ | Rank this year |
|---|---|---|---|
| Weekly change | −0.93% | −7.25% | KOSPI: rank 20 of 33 weeks |
| Weekly high–low range | +12.75% | +9.68% | KOSPI: rank 10 of 34 weeks |
| Friday close | 6,912.95 | 801.94 | — |
Weekly flows — who bought and who sold
A window on how much foreign investors, retail investors, investment firms and pension funds each bought and sold over the week
Institutional investors net sold ₩2,269.5bn on the week while retail absorbed ₩1,941.3bn — the clearest intra-week divergence came on Wednesday’s crash day
| Day | KOSPI | Foreign investors | Retail investors | Investment firms | Pension funds |
|---|---|---|---|---|---|
| Tue (08.18) | −1.55% | +₩91.4bn | +₩742.0bn | −₩669.1bn | −₩80.6bn |
| Wed (08.19) | −5.80% | −₩3.47tn | +₩4.64tn | −₩1.36tn | +₩73.1bn |
| Thu (08.20) | +5.89% | +₩1.71tn | −₩2.27tn | −₩317.7bn | −₩181.6bn |
| Fri (08.21) | +0.88% | −₩176.0bn | −₩1.17tn | +₩72.7bn | +₩46.4bn |
| Weekly total | −0.93% | −₩1.85tn | +₩1.94tn | −₩2.27tn | −₩142.7bn |
For the four-session week, institutional investors (investment firms) net sold ₩2,269.5bn, foreigners net sold ₩1,850.4bn, and pension funds net sold ₩142.7bn; retail investors absorbed ₩1,941.3bn in net purchases.Wednesday’s crash session was the defining day: foreigners sold a net ₩3,472.6bn and institutions shed ₩1,355.4bn, while retail stepped in with ₩4,635.7bn in net buying — the largest single-session retail absorption of the week.Thursday’s rebound saw foreigners return as buyers at ₩1,706.8bn net, and retail reversed to net sell ₩2,271.2bn, a pattern broadly consistent with retail selling into recoveries after crash-day accumulation.
What each group bought and sold
A window on the stock each group bought most and sold most that week
Samsung Electro-Mechanics was the week’s most contested stock — foreigners sold ₩919.0bn net while retail bought ₩1,287.1bn net, and pension funds also net sold
| Investor group | Bought most | Sold most |
|---|---|---|
| Foreign investors | Samsung Electronics+₩711.7bn | Samsung Electro-Mechanics−₩919.0bn |
| Retail investors | Samsung Electro-Mechanics+₩1.29tn | SK hynix−₩1.23tn |
| Investment firms | Samsung Electronics (Pref.)+₩134.3bn | SK hynix−₩1.07tn |
| Pension funds | SK hynix+₩240.0bn | Samsung Electro-Mechanics−₩145.8bn |
Samsung Electro-Mechanics split the investor base three ways: foreigners net sold ₩919.0bn (their top net-sale for the week across the 70-name universe), retail net bought ₩1,287.1bn (retail’s top net-purchase), while pension funds net sold ₩145.8bn (their top net-sale).SK hynix was the other major cross-actor divergence: retail net sold ₩1,233.2bn and institutional investors net sold ₩1,073.3bn, while pension funds net bought ₩240.0bn — the National Pension Service’s largest net purchase of the week.
The week’s events
A window on what moved the market over the week and what followed, in order
U.S. Treasury yield volatility drove the week’s narrative — from Wednesday’s SOX-shock selloff to Thursday’s liquidity-backstop rebound
| Day | Layer | Event | Outcome |
|---|---|---|---|
| Tue | Industry | Nvidia guarantees 150 trillion won for OpenAI data center…circular financing flagged | KOSPI −1.55% |
| Tue | Industry | SoftBank invests $200M in Swiss construction robot startup | KOSPI −1.55% |
| Tue | Policy | Ruling party shows signs of a rift over property taxes — “needs fixing” vs. “stick to the government plan” | KOSPI −1.55% |
| Wed | Macro | KOSPI whipsaws on a jump in US Treasury yields — SK hynix shareholder-return effect in focus | KOSPI −5.80% |
| Wed | Industry | KOSPI plunges 5.8% on global sovereign yield rise, US data center delay concerns | KOSPI −5.80% |
| Wed | Industry | SK Hynix to acquire, cancel 40 trillion won in own shares…largest domestic buyback | KOSPI −5.80% |
| Thu | Macro | Treasury yields ease on the US Treasury’s ‘liquidity lifeline’ — New York stocks edge higher | KOSPI +5.89% |
| Thu | Macro | New York stocks edge higher as US Treasury yields fall — Dow +0.2% | KOSPI +5.89% |
| Fri | Macro | New York stocks fall across the board as US Treasury yields rebound — Dow −1.3% | KOSPI +0.88% |
| Fri | Macro | New York stocks fall across the board as US Treasury yields rebound — Dow −1.3% | KOSPI +0.88% |
Wall Street scoreboard — weekly summary
A window grading, cumulatively, whether the stance of US investment bank reports matched reality three days later
Wall Street scorecard: 14 hits in 26 calls (54%) cumulative; no new calls were graded this week
The scorecard tracks brokerage price targets and sector calls against the named stock’s three-session return; a call is scored a hit if the direction is confirmed.Through this edition the running tally stands at 14 hits in 26 graded calls (54%) — no new calls were added or settled this week; the five most recent graded calls span Bernstein, Nomura, JP Morgan, Morgan Stanley, and Barclays, with outcomes ranging from +1.41% to −19.23% three sessions after publication.
| Institutions | Report | Actual | Verdict |
|---|---|---|---|
| Bernstein (06.22) | Samsung Electronics—Bernstein raises targets for Samsung, SK Hynix, Micron…”Rising memory prices ease AI cost pressures” (Positive) | +1.41% | ✓ |
| Nomura (06.24) | Samsung Electronics—Nomura “590K→670K”…Samsung target raised again (Positive) | −5.14% | ✗ |
| JPMorgan (06.25) | KOSPI—JPMorgan raises 12-month target to 12,500…”Maximize Korean equity weight” (Positive) | −5.08% | ✗ |
| Morgan Stanley (07.13) | SK Hynix—Semiconductor overbought warning (memory winter precedent) (Negative) | −0.16% | ✓ |
| Barclays (07.23) | SK Hynix—Target price $330 (117% upside) (Positive) | −19.23% | ✗ |
The week’s lesson
A window for what to carry past the end of the week
Four sessions, a 12.75% swing, and three distinct investor reversals — this week’s tape offers sharply defined lessons
A week defined by external rate shocks, intraday reversals, and bifurcated index performance resists any single-cause reading — multiple factors were in motion simultaneously on each session.The judgment is each reader’s own.