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Chips Rally Overnight — Will Friday Foreigners Follow or Fade? — Korea Market Pre-Open, Aug 14, 2026

Friday, August 14 (2026) opens with overnight U.S. and Nikkei futures all in the green, and Thursday’s NXT aftermarket data showing Samsung Electro-Mechanics up 12.06%, SK hynix up 4.45%, and Samsung Electronics up 2.74% — a strong directional signal from the semiconductor complex.The central questi

The Silmari
A daily data newsletter on the Korean stock market — silmari, ‘a clue: the loose end that unravels the knot’
① Pre-Open 07:302026.08.14 Fri · No. 12Crash-precursor score 3/6 — short-surge and ADR signals lit; sell-acceleration and sentiment-90+ at zero
① Pre-Open · published 07:30 KST · before the open
01 · VerdictRegular session confirmed 15:30 KST

Today’s Calls

Chips Rally Overnight — Will Friday Foreigners Follow or Fade?

Friday, August 14 (2026) opens with overnight U.S. and Nikkei futures all in the green, and Thursday’s NXT (Nextrade)Korea’s alternative trading system (ATS), which runs pre-market and after-market sessions outside KRX hours and offers a real-time read on demand before and after the main session.NXT aftermarket prices — available from around 15:30 to 20:00 KST — are used in this letter as an early signal of the following morning’s open direction. aftermarket data showing Samsung Electro-Mechanics up 12.06%, SK hynix up 4.45%, and Samsung Electronics up 2.74% — a strong directional signal from the semiconductor complex.The central question is whether foreign investors confirm the move: in the 2026 regime, foreigners have been net buyers on only 23% of Fridays (n = 30), and Thursday’s one-week KOSPI foreign net purchase of ₩2.64tn alongside a retail net sell of ₩4.84tn over the same period places this session at a potential inflection point between continuation and profit-taking.

Key points
01Overnight futures all positive: S&P 500 futures +0.61%, Nasdaq 100 futures +1.09%, Nikkei CME +1.09% as of 05:00 KST — broad global bid heading into the Seoul open.
02Thursday NXT aftermarket snapshot (19:25 KST, 20-min delay): Samsung Electro-Mechanics +12.06%, SK hynix +4.45%, SK Square +6.93%, NAVER +5.34% — semiconductor and platform names led aftermarket volume of ₩19.38tn.
03Friday foreign-buying probability in the 2026 regime is 23% (n=30); the one-week KOSPI foreign net purchase stands at ₩2.64tn but retail has sold a net ₩4.84tn over the same window — profit-taking pressure is the structural headwind to watch at the open.
04Crash-precursor score is 3/6 with short-surge and Advance-Decline Ratio (ADR)The ratio of advancing stocks to declining stocks in a given market on a given day; an ADR below 1.0 means more stocks fell than rose.A sustained low ADR signals deteriorating market breadth — rallies driven by a handful of large-caps while most stocks decline are considered fragile. signals active; in the current regime (2026–), short-surge events have been followed five days later by an average KOSPI return of −0.87% with a 51% down-probability (n=105) — not a decisive bear signal, but a caution flag that warrants watching foreign futures positioning at the open.
02 · Prediction2 calls · posted 07:30 KST

Today’s Calls

Where the day’s calls are placed by number — grading starts with the Early Session edition

Today’s forecasts: KOSPI +0.2~+1.0%, KOSDAQ +0.5~+2.0% (pre-open; not yet scored)

Two predictions are on the board for Friday, August 14 (2026) — P1 calls for KOSPI to rise +0.2% to +1.0% on the day, and P2 calls for KOSDAQ to rise +0.5% to +2.0% in the morning session.This is the pre-open edition published at 07:30; neither prediction is subject to scoring yet — results will be evaluated in the evening edition once closing data is confirmed.

calls placed today
2 issues
posted 07:30 KST
Direction grading
from the 10:00 Early Session edition
Magnitude grading
settled in the 20:00 Final Edition
Call ① KOSPIThe KOSPI is more likely to rise
Band +0.2~+1.0% · full day
Morning rationaleUS CPI softens, S&P500 supported above all-time high; Friday sees peak foreign selling, 4-day rally profit-taking pressure limits gains
Call ② KOSDAQThe KOSDAQ is more likely to rise
Band +0.5~+2.0% · morning
Morning rationaleTesla +3.80% surge → current regime KOSDAQ avg +2.94% next-day rise probability 71% (n=21), accompanied by Koo Kwang-mo·Jensen Huang physical AI collaboration news

No individual stock or sector predictions were logged for today’s session; the two market-level calls (P1, P2) cover the full scope of today’s pre-open forecast record.

03 · OvernightOvernight, confirmed — previous U.S. session

The world overnight — how the US session ended

A window on what happened in the US market overnight

S&P 500 closed at 7,798.99 (+0.65%) Thursday; Nasdaq at 26,803.03 (+0.81%) — tech leads into Korean open

Nasdaq26803.03 (+0.81%· as of 2026-08-13)
S&P5007798.99 (+0.65%· as of 2026-08-13)
Philadelphia Semiconductor Index (SOX)A U.S. exchange index tracking the share prices of major semiconductor design and manufacturing companies, widely used as a leading indicator for the Korean chip sector.Korean semiconductor names — Samsung Electronics, SK hynix — have historically shown a same-day or next-day correlation with SOX moves above 0.5% in absolute terms.Semiconductors12456.0 (+0.46%· as of 2026-08-13)
Dow53839.99 (+0.13%· as of 2026-08-13)
iShares MSCI South Korea ETF (EWY)A U.S.-listed exchange-traded fund that tracks the MSCI Korea Index, providing the most liquid single-ticker proxy for foreign investor sentiment toward Korean equities.When EWY trades at a premium or discount to KOSPI fair value, it often signals overnight foreign demand that precedes the Seoul open.(Korea ETF)178.62 (+1.56%· as of 2026-08-13)
Dollar index99.95 (−0.06%· as of 2026-08-13)
U.S. 10-year Treasury4.64 (−0.88%· as of 2026-08-13)
Nikkei 225 (prior session)67524.06 (+0.83%· as of 2026-08-12)
USD/KRW (prior Seoul session)1420.3 (+0.09%· as of 2026-08-13)

Wall Street closed higher on August 13 (2026): the S&P 500 at 7,798.99 (+0.65%), the Nasdaq at 26,803.03 (+0.81%), and the SOX semiconductor index at 12,456.0 (+0.46%).The SOX gain of +0.46% falls just below the 0.5% threshold used in the Korea-U.S. cross-follow definition, meaning today does not automatically qualify as a confirmed semiconductor-follow day; in 2026 YTD data, Korea followed U.S. direction on 39 of 139 sessions when a clear signal was present.The Wall Street brokerage scorecard shows an overall three-month hit rate of 54% (15/28), with notable variance by institution; no brokerage reports specific to today’s Korean open have been confirmed in the data available at 07:30.

04 · Cross-followingMeasured in 2026

Korea–U.S. mutual following — overnight grading

A window on which market followed which

U.S. equity futures extend Wednesday’s gains — S&P 500 futures +0.61%, Nasdaq 100 futures +1.09% overnight

As of the 05:00 KST snapshot on August 14 (2026), S&P 500 futures (ES=F) stood at 7,825.25, up 0.61% from the August 13 15:00 KST reference close; Nasdaq 100 futures (NQ=F) were at 30,214.25, up 1.09%; and Nikkei CME futures (NIY=F) were at 69,125, also up 1.09.These are CME-linked proxies for overnight U.S. and Nikkei conditions; the Korea 200 night session is not captured here, and the figures carry an estimated ±1-hour timing margin.

In 2026 year-to-date data (139 sessions), Korea has followed the U.S. direction on 39 days, the U.S. has followed Korea on 30 days, both moved in tandem on 46 days, and neither followed the other on 24 days.On days when the overnight SOX move is positive but below 0.5%, the data definition flags no directional signal; last night’s SOX reading (August 13 close: 12,456.0, +0.46%) sits just below that threshold, so today’s KOSPI opens without a confirmed semiconductor-follow signal from the U.S. side.

Days Korea followed the U.S.39 days
Days the U.S. followed Korea30 days
Both ways46 days
Sample139 days

Overnight SOX ↔ same-day KOSPI in the same direction (|SOX| ≥ 0.5%) = Korea following · same-day KOSPI ↔ that night’s SOX in the same direction (|KOSPI| ≥ 0.5%) = the U.S. following

05 · Night windowOvernight indicators

Night window —EWYofficial indicator

A window on what overnight futures foreshadow for the next day’s open

Overnight U.S. and Nikkei futures all positive — S&P 500 futures +0.61%, Nikkei CME +1.09% at 05:00 KST

Nasdaq26803.03 (+0.81%· as of 2026-08-13)
S&P5007798.99 (+0.65%· as of 2026-08-13)
SOX semiconductors12456.0 (+0.46%· as of 2026-08-13)

The three CME-linked overnight proxies — S&P 500 futures at 7,825.25 (+0.61%), Nasdaq 100 futures at 30,214.25 (+1.09%), and Nikkei CME futures at 69,125 (+1.09%) — all advanced between the August 13 15:00 KST close and the 05:00 KST snapshot on August 14 (2026).These are U.S. and Japan exchange-linked proxies, not the Korean K200 night session; the figures carry an estimated ±1-hour timing margin, and how they translate to KOSPI at the open depends on whether foreign futures positioning — which turned net short by 504 contracts on August 13 — reverses at the open.

06 · Pre-openPre-open check

Pre-open08:00~09:00single-price auction (open/close)The single-price auction window (before the open and just before the close), where orders are pooled and matched at once.When large volume crowds into this window, a gap is created.forecast

A window on where the pre-open auction is pulling the opening price

Nikkei CME futures at 69,125 (+1.09%) — gap-up open for Seoul chips possible; Friday flow pattern the key test

With Nikkei CME futures up 1.09% and Nasdaq 100 futures up 1.09% as of 05:00 KST, the pre-open call-auction (08:30–09:00) will likely test whether semiconductor names — Samsung Electronics, SK hynix, Samsung Electro-Mechanics — can hold the directional gap suggested by overnight U.S. and Japanese futures; no intraday call-auction data is yet available at 07:30.Given that Thursday’s NXT snapshot (19:25 KST, 20-minute delay) showed Samsung Electro-Mechanics up 12.06% and SK hynix up 4.45%, the question for the open is whether foreign buying — which has occurred on only 23% of 2026 Fridays — confirms or fades the aftermarket direction.

KOSPIClose6,813.34· same-day+3.56%
KOSDAQClose861.37· same-day+0.29%
Historical contextFriday 2026-regime stats (n=30): KOSPI average move +0.57%, up-probability 57%, average range 3.93%; foreign net buying probability 23%.
07 · ReviewPrevious trading day (08.13) finalized

Previous-Day Review

A window that retraces what happened in the previous session

Thursday August 13 went 8-for-8 — foreign net selling began on day three of the rally

KOSPIClose6,813.34· same-day+3.56%
KOSDAQClose861.37· same-day+0.29%
08 · Fear gaugeStanding gauge8 factors · based on previous trading day (08.13) · percentile: current regime (2026)

The Silmari Fear Gauge

A window measuring market anxiety through volatility, margin lending and short selling

Sentiment gauge score at 3 — short-surge and ADR signals active ahead of Friday open

Volatility percentile
94
Silmari Fear Gauge percentile basis — to be stated
Margin balance, 5-day change7.04 — Change in Leveraged Purchases — Larger increases create greater forced liquidation pressure on declines ·as of 08.12
Forced-liquidation share0.6 — Share of Forced Liquidations — Higher ratio signals greater mechanical selling pressure ·as of 08.12
Short-interest surge multiple1.49 — Short bets multiplied how many times in 5 days — Steep surge is a warning signal ·as of 08.10
Retail buying intensity on down days0.0 — N/A — not a down day (3.56%)
Consecutive no-trigger down days0.0 — N/A — No-trigger declines did not continue
KOSPI 20-day realised volatility6.04 Risk · top 6%· Recent 1-month volatility size — dashboard’s core metric
Leveraged-ETF share of turnover9.9 Risk · top 28%· Leveraged product fund concentration — short-term sentiment gauge

The composite crash-precursor score stands at 3 as of this morning’s pre-open read, with two of four sub-signals lit: the ADR reading (sourced from the U.S. session of 2026-07-28, at −16.7%) and a short-selling surge flag (based on the short-balance filing date of 2026-08-10, reflecting T+2 disclosure).The sell-acceleration and sentiment-90+ triggers remain at zero; the momentum gauge is not yet compiled for today’s session.

In the current regime (2026–), short-surge events (defined as short balance doubling within five trading days on positions of 50,000 shares or more) have been followed five days later by an average KOSPI move of −0.87% with a 51% probability of decline — against a regime baseline of +2.98%, implying an excess return of −3.85 percentage points (n = 105).Over the most recent six months, the five-day post-surge average has been −0.98% with a 53% down-probability (n = 100), suggesting the drag has been consistent across time windows within this regime.

No scheduled macro trigger (central bank decision, CPI print, or major earnings) has been flagged in the data available at 07:30 on Friday, August 14 (2026).Friday is statistically the weakest day for foreign net buying in the 2026 regime — foreigners have been net buyers on only 23% of Fridays (n = 30), with an average net flow of −₩1.43tn; today’s flow data has not yet been collected.The judgment is each reader’s own.

09 · FX windowFX window — previous close

The won — the signal is the speed of the move, not its direction

A window on the pressure the won-dollar rate puts on foreign flows

Won holds near ₩1,420 per dollar; yen cross at ₩890 per 100 yen

USD/KRW₩1,420.2 (strip, Aug 13)
JPY/KRW (100 yen)₩890.35
U.S. Dollar Index (DXY)A measure of the U.S. dollar’s value against a basket of six major currencies; a rising DXY generally means a stronger dollar and a weaker won.A stronger dollar tends to increase foreign selling pressure on Korean equities as returns measured in dollars erode.99.96 (−0.06% on Aug 13)
U.S. 10-yr yield4.64% (−0.88% on Aug 13)

The won-dollar rate was last marked at 1,420.2 in the cumulative strip data, with the dollar index (DXY) at 99.96 — down 0.06% on the day as of August 13.The yen-won cross (100 yen per won) was 890.35; a firmer yen relative to this level would historically add mild upward pressure on foreign selling of Korean equities, though intraday FX data for August 14 (2026) has not yet been collected.

10 · KOSDAQ windowKOSDAQ · pre-open 07:30 KST · August 14, 2026 (Friday) · today’s closing data not yet available

The SilmariDecouplingWhen two markets that used to move together break apart and move separately.The wider the gap, the less any single index can tell you about the market.Gauge

A window on the pattern in the KOSPI–KOSDAQ decoupling

KOSDAQ breadth deteriorated Thursday — ADR fell to 0.63 — as today’s session awaits pre-open confirmation

KOSPI · KOSDAQ close (08.13)6,813.34 · 861.37
Previous session change+3.56% · +0.29%
Previous-session gap (KOSPI − KOSDAQ)+3.27%p
Cumulative since start of year (through 08.13)+58.10% · −8.90%
Silmari Decoupling Gauge — year-to-date gap+67.00%p
11 · WarningToday’s warning score of 3 = crash alert — thresholds: 3+ crash alert · 2 caution (small sample)

Warning

A window flagging in advance where today’s session calls for caution

Precursor score at 3; retail net selling of ₩2.74tn Thursday signals profit-taking phase in progress

The crash-precursor composite stands at 3 out of a possible 6, with the ADR and short-surge sub-signals active; in the current regime (2026–), this score level has historically been associated with near-term underperformance relative to the baseline but does not carry a fixed directional verdict — past samples show mixed outcomes.Thursday, August 13 saw retail investors sell a net ₩2.74tn on a single day — consistent with the lesson flagged after August 13’s session: large-scale retail profit-taking followed by a potential reversal-buy entry the next day has historically served as a late-bus signal, where new buying momentum tends to exhaust.On Fridays in the 2026 regime, KOSPI has risen on 57% of sessions (n = 30) but foreign investors have been net buyers on only 23% of Fridays — if foreigners begin net selling at the open, the 20260813 lesson suggests monitoring whether retail steps in on the opposite side, as that cross-over has previously marked the entry into a late-stage momentum window.

Sources: Korea Exchange · NXT · own measurements · regular session confirmed 15:30 KST · The Silmari editorial desk.
This edition organises and explains publicly available market data. It is not investment advice. Predictions and their scores are preserved without revision — the judgement is yours.