· by The Reader
SKHY memo (neutral 45), Oct 29, 2026
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Summary
SK hynix remains the central supplier of HBM into AI accelerators, and the Motley Fool transcript of the October 28, 2026 Q3 call is headlined on record revenue and profit from AI memory demand, but this session did not retrieve the actual quarterly figures, capex guidance or HBM mix. With a 6-K filed October 29 that explicitly says no decision has been made on a reported Won 60 trillion Solidigm NAND fab, the documented record is too thin to carry a directional call, so the signal is neutral.
Variant view
The market is trading this as a binary on AI memory pricing: the shares fell from 195.13 on October 2 to 131.69 on October 22, then jumped to 164.70 on October 28 when Q3 results landed. That round trip says positioning, not fundamentals, moved the quote. This memo does not take the other side of the bullish AI memory thesis; it declines to underwrite it today because the only primary document retrieved is a rumor clarification, and the transcript body could not be parsed for revenue, margin or 2027 capex.
Evidence
The 6-K filed October 29, 2026 (accession 0001193125-26-436872) responds to a Maeil Business Newspaper report that Solidigm, the US subsidiary, is pursuing roughly Won 60 trillion for a new NAND flash plant in the United States. The company states that Solidigm is reviewing measures to strengthen competitiveness and expand capacity, but that no matters have been determined, and it will disclose further either when details are confirmed or within one month. That is a material capital commitment left open, not resolved.
The Q3 2026 earnings call was held October 28, 2026. The Motley Fool transcript page carries the description that AI memory demand drove record revenue and profit. The transcript body did not render in this session, so no revenue, operating margin, HBM share of DRAM bits or 2027 capex figure is cited here. The absence is the point: the bullish case rests on numbers that were not read.
Price action frames the risk. Closes went 195.13 on October 2, 147.55 on October 14, 131.69 on October 22, then 164.70 on October 28 and 162.09 on October 29. That is a 33 percent drawdown and a 25 percent recovery inside four weeks. Thirty day change is negative 11.98 percent and one year change is negative 3.52 percent, against a 52 week range of 126.79 to 198.63.
Four separate 6-K filings were lodged on October 28 and two more on October 26, alongside the October 29 clarification. The filing cadence is consistent with a company making repeated disclosures around results and around capital plans. None of those documents were read in full here.
Secondary reporting places the Solidigm question in context: coverage describes the IPO plan being scrapped, Solidigm seeking a new funding path for a US fab, and a Bloomberg sourced figure of roughly 45 billion dollars for the plant. If the parent must fund that balance sheet item directly, free cash flow available for shareholder return competes with a very large NAND build at a moment when the HBM cycle is the earnings driver.
The AI exposure rating in the internal record is 80, with growth and pricing set by accelerator demand. That is a feature in an upcycle and a concentration risk otherwise. It argues for owning the name on documented numbers rather than on a headline description of a call.
Bear case
Memory is cyclical and the buy side has already paid for the upcycle. A Won 60 trillion NAND commitment, funded on balance sheet after the Solidigm IPO was dropped, would land into a NAND market that is not the HBM market and does not share its pricing power. If HBM qualification slips to a competitor at any major accelerator customer, or if accelerator order books normalise in 2027, both volume and price fall at once, and the capex is already sunk.
What would change my mind
First, retrieving the Q3 2026 call text or the results 6-K with actual revenue, operating margin and 2027 capex, plus HBM supply commentary, which would allow a priced view rather than a withheld one. Second, the promised follow up disclosure on Solidigm within one month: a confirmed multi trillion won US NAND commitment with a named funding structure, or a formal shelving of it, would resolve the largest open capital question.
Market data as of the close on . Prices are end of day, not live.
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