Foreign investors sold more than KRW 3 trillion of Samsung Electronics and SK hynix. Could they rebound when Micron reports early tomorrow morning? I'd like to know how my chip stocks might fare under each outcome.

Why Micron's earnings are a "proxy report card" for Korean chips

Micron is the first of the three memory makers to report quarterly results. Samsung Electronics and SK hynix don't release final results until late October, so foreign investors use Micron's numbers to gauge Korean memory's next quarter in advance. Foreign investors' sale of more than KRW 3 trillion of the two stocks on 9/28 was largely about reducing risk ahead of Micron's release (early morning 10/1 Korea time).

The company's Q4 guidance is revenue of $50 billion (±$1 billion), EPS of $31 and a gross margin of about 86%. The market consensus is revenue of $50.8 billion, near the top of guidance (Yahoo Finance). In other words, this quarter's numbers are already fully priced in. What will move the stock is next quarter's (fiscal 2027 Q1) guidance, and the market expects revenue of about $57 billion and EPS of about $35 (TIKR/Yahoo Finance, 2026-09-28).

Three scenarios

The single most important sentence is how management describes 2027 supply and demand. Micron's management previously said "2027 will be even tighter than 2026" (TIKR, 2026-09-28). If that language holds, it means the memory boom will last another year; if it softens, it becomes a warning that prices could turn down ahead of new fabs coming online in mid-2027 and late 2028.

Samsung Electronics and SK hynix react differently to the same outcome

Both stocks fell 5%, but foreign investors' intentions differ. Just before the holiday, foreign investors bought KRW 2.5 trillion of Samsung Electronics while selling SK hynix (Financial News, 2026-09-26). SK hynix, which holds the HBM lead, already has expectations fully priced in, so "good numbers" are not enough; it needs "better numbers." Samsung Electronics, by contrast, has less of its HBM catch-up priced in, leaving it more room to hold up as long as guidance is merely decent.

SK hynix also faces a separate variable: reports that Solidigm is pursuing a U.S. listing. The holding-company discount debate may continue regardless of Micron's results. A wild card on Micron's side is a Taiwan union strike vote in early October. Of Micron's roughly $54 billion in noncurrent assets, about $19 billion is in Taiwan (TIKR, 2026-09-28).

Where things stand according to signals

Micron (MU) closed at $1,082.28 on 9/25, above its 10-day (1,014.63), 50-day (941.62) and 150-day (766.50) moving averages, with entry_ok True for five straight sessions. Its trailing buffer is 16.25% and its drawdown from the peak is -13.75%. Even after the -4% drop on 9/28 the trend is intact, but a one-day post-earnings move could significantly erode the buffer. The chip ETF (SMH) also held above its 10-day (577.48) and 50-day (565.89) moving averages at $606.56 on 9/25, with entry_ok True and a 10.28% buffer. The Korea ETF (EWY) flipped between entry_ok False and True from 9/21 to 9/25 with a thin buffer of 2.63-7.20%, making it the least stable of the three.

What should investors do?

• Adding to chip positions before earnings is close to a coin toss. If you already hold them, it's not too late to decide after seeing the Korean market's reaction on the first trading day after the release (10/1)
• If you pick one Korean chip stock, Samsung Electronics, which is less shaken in the in-line scenario, is more defensive than SK hynix
• Watch Korea's September exports (10/1), released the same day. If both Micron's guidance and chip exports are strong, the 9/28 foreign selling will prove to have been temporary profit-taking

Detailed charts and signals for other stocks are available on the /signals dashboard.