A second straight day of profit-taking gutted the semiconductor toolchain — FormFactor −16.0%, Amkor −12.9%, KLA −11.5% — even as a weak jobs print sent the Dow to a record, while SK hynix rebounded 10.9% in Seoul.

SK hynix (000660.KS) rebounded 10.9% in its latest Seoul session, closing Friday at ₩2,425,000 and clawing back part of the 14.6% collapse it took a session earlier, when a US class-action alleged the big three memory makers throttled conventional DRAM output to inflate prices. SK hynix sits at the center of the HBM-memory chokepoint — roughly 56% of global HBM revenue, the stacked memory every leading-edge accelerator is bolted to — and this move is the memory complex stabilizing after the litigation shock, not fresh demand. It also lands days before SK hynix's planned Nasdaq depositary-receipt listing (ticker "SKHY," expected around July 10), which will put the HBM chokepoint directly on the US tape. Note the divergence the number hides: SK hynix's own session ran green while the US semiconductor tape had a second brutal red day.

That red day's worst name was FormFactor (FORM), down 16.0% to $123.59, as the profit-taking that began a session earlier deepened across the test-and-metrology layer. FormFactor builds the probe cards used to test HBM and logic die — a quiet HBM-memory chokepoint — and it fell furthest precisely because it had run furthest: the Philadelphia Semiconductor Index dropped 6.7% on the session after roughly doubling in the second quarter. This was a valuation unwind, not a demand signal. There was no company-specific catalyst; the market simply took profits on a stretched AI-hardware trade after June payrolls came in at +57k against roughly 110k expected, a weak print that rotated money toward the Dow's record close and away from high-beta chips.

The damage clustered in the back-end and tool chokepoints. Advanced packaging led lower — Amkor (AMKR) −12.9% to $69.65, Onto Innovation (ONTO) −12.5% — alongside process-control and litho names KLA (KLAC) −11.5% to $235.55 and Lam Research (LRCX) −10.2%, with substrates-and-materials supplier Entegris (ENTG) −11.2%. The optical-interconnect chokepoint broke too: Applied Optoelectronics (AAOI) −13.0%, Coherent (COHR) −9.6%. Micron (MU) fell 5.5% to $975.56 and CoreWeave (CRWV) −4.6% on the accelerator-capacity node, with Meta (META) −4.9%. The one green corner was the power-grid chokepoint furthest from the silicon: Cleveland-Cliffs (CLF) +4.7% on electrical steel, Constellation (CEG) +1.2%, Talen (TLN) +1.1% — the data-center-power names held as the compute-hardware complex sold.

The calendar now turns to hard prints. PJM's 2028/2029 Base Residual Auction closes July 7, a direct read on the data-center power premium Talen and Constellation trade on. ASML (July 15/16) and TSMC (July 16) then deliver the first Q2 checks on whether leading-edge tool and foundry demand matches the AI narrative, followed by Intel and KLA on July 23 and 30, and SK hynix's own Q2 on July 29 — its first as a soon-to-be US-listed name.