A synchronized top, then a synchronized break

The cohort topped almost together: Unimicron on 27 May at NT$1,080, TDK 5 June at ¥4,111, Samsung Electro-Mechanics 19 June at ₩2,270,000, Ibiden and Murata both 22 June at ¥26,425 and ¥12,250, and Kinsus 30 June at NT$891. Every one has fallen since. Through the 22 July price cutoff the 30-day moves were 009150.KS -39.6%, Murata -32.1%, Ibiden -30.9%, TDK -23.5%, Unimicron -9.8% and Kinsus flat. Later FMP snapshots put drawdowns from peak at roughly -60%, -54%, -43%, -28% and -17% for SEMCO, Murata, Ibiden, TDK and Unimicron.

The Samsung Electro-Mechanics move is real, not a corporate-action artifact — OHLCV is continuous with normal 0.3–1.5m share volumes — but it is violent rather than gradual: -9.8% on 7 July, -10.2% on 8 July, -14.9% on 13 July, then +12.1% on 15 July. Of the eight names in the original cohort only six are analysable: Yageo has no local history, and Shinko is gone entirely after JIC Capital's ¥5,920/share tender offer completed in March 2025 and the shares were delisted.

The fundamentals went the other way

Every demand-side leg of a distribution thesis fails. Murata, SEMCO and Taiyo Yuden posted MLCC book-to-bill ratios of 1.30, 1.31 and 1.25 in late June, described as post-pandemic highs. Instead of Taiwanese price competition, Yageo launched its broadest capacitor price hike in years on 1 July, extending increases to direct customers for the first time this cycle. Industry-wide, high-end MLCC lead times stretched from 8 to over 20 weeks with capacity unlikely to catch up before late 2027 — though TrendForce frames it as AI strength against a weak consumer segment, not a uniform boom.

Substrates are equally tight: FCBGA demand exceeds capacity by more than 50%, with Ibiden's ¥500bn plan only reaching first output in fiscal 2027, while Unimicron, Kinsus and Nan Ya PCB run at full utilisation. SEMCO itself guided Q2 revenue of ₩3.3tn and operating profit of ₩398.3bn, above consensus. Consensus FY2026–27 revenue and EPS growth for the cohort is still accelerating.

What actually moved

The KOSPI peaked at 9,114.55 on 22 June — the same week the cohort topped — then collapsed 10.84% on 28 July to 6,023.66 after China's first domestic immersion DUV tools entered service at SMIC and CXMT, knocking Samsung and SK Hynix down ~13-14%. The sell-off spread across Seoul and Tokyo, matching the cohort's cross-market behaviour.

Two residual observations. Valuations remain demanding — Unimicron 127x trailing, Ibiden 106x, SEMCO 85x — and every name still sits 19% to 124% above its 200-day average. And the signal layer is badly stale: through 22 July the band file still showed SEMCO, Kinsus, Ibiden and Murata in unbroken strongly bullish despite 24-41% drawdowns.