SK hynix jumped 12.7% in Seoul on a fresh buyback and Marvell popped 9.8% on a $12.2B Google deal, but the chip-equipment choke sold off again as the market repriced AI capex.

The memory-bandwidth choke led, and it led on capital return. SK hynix rose +12.7% in its latest Seoul session to ₩1,691,000 after the company set a share-repurchase program of roughly 24.07 million shares — about 3.3% of shares outstanding — with the buyback window opening August 20 and running to November 19. The signal matters more than the size: SK hynix supplies the majority of the world's HBM and about two-thirds of NVIDIA's HBM4, so management buying its own stock into a volatile tape is a direct read on the durability of the memory choke that gates every accelerator. The move also unwound the prior session's −9.7% Seoul slide, leaving the name whipsawing inside the same HBM-supercycle debate that has run all month.

The laggard was the metrology-and-test choke, and it was the day's structural tell. FormFactor fell −7.6% to $114.95 on no company-specific news, derating with the wider chip-equipment complex as investors repriced the sustainability of AI infrastructure spending — a reaction sharpened by reports that Anthropic's annualized run-rate and out-year revenue projections landed below the locked-in-capex assumptions the sector had been priced against. Probe cards are the choke that gates wafer-sort throughput; when the market questions the buildout, the tool layer levered to it moves first and hardest.

The rest of the equipment stack sold with it while two catalysts cut the other way. Lam Research fell −6.3% to $307.17, Amkor −7.2% to $50.89, Applied Optoelectronics −7.0% to $122.19, Coherent −6.2% to $287.47, Lumentum −5.2% to $827.60, Onto Innovation −5.0% to $299.50, Broadcom −4.6% to $362.48, Credo −4.5% to $234.82, ASML −2.8% to $1,751.73; on the demand side Micron slipped −0.4% and TSMC −0.3%, with SoftBank −5.1% and CoreWeave −2.5% to $90.87. Against that, Marvell jumped +9.8% to $237.27 after a filing disclosed Google can purchase up to $12.2 billion of Marvell stock — 58,970,907 shares at $206.58 — tied to custom-silicon procurement through fiscal 2033, giving Marvell an anchor customer at all three US hyperscalers. The power-and-thermal choke was the other refuge: Amazon +2.5% to $265.84, Constellation +2.8% to $274.17, Ecolab +2.0% to $285.62.

The calendar decides the next leg, and it is dense. Marvell reports fiscal Q2 today, August 20 — the first read on the custom-silicon ramp behind the Google deal — with Hot Chips at Stanford August 23–25, Fabrinet's fiscal Q4 on August 24, and NVIDIA, the demand signal for the whole stack, on August 26. Broadcom's fiscal Q3 lands September 3 and Ecolab's ~$4.75B CoolIT close is guided for Q3. The tell is whether the equipment selloff is a genuine capex reset or a positioning flush that the hyperscaler prints reverse.