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SK hynix Japan Fab, Chongqing Sale, Solidigm IPO: What DART Says

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SK hynix (KRX: 000660; Nasdaq: SKHY) has three open “unconfirmed” disclosures on DART, Korea’s corporate filing system. They cover a reported Japan fab, a reported stake sale in its Chongqing, China packaging plant, and a reported ₩5 trillion pre-IPO round at its US subsidiary Solidigm. Each filing says the matter is under review, nothing is decided, and the company will file again by a set date: Dec 3 (Solidigm), Dec 8 (Chongqing) and Dec 17, 2026 (Japan).

TL;DR

  • All three are second-round updates (Sept 4, 9 and 18, 2026) that replace August’s one-month promises with three-month ones.
  • None confirms or denies the reported deal.
  • Nasdaq ADS holders received English versions on Form 6-K the same days.

What happened

Three press reports in August led to filings:

  • Solidigm pre-IPO (Aug 5). The Korea Economic Daily reported that Solidigm was pursuing a pre-IPO raise. SK hynix filed a clarification the same day.
  • Chongqing stake sale (Aug 10). After a report that SK hynix was trying to sell a stake in its Chongqing plant, which the report valued at about ₩4 trillion, the Korea Exchange (KRX) sent an inquiry at 10:10 a.m. Seoul time. SK hynix answered at 3:36 p.m.
  • Japan fab (Aug 21). The KRX asked at 11:35 a.m. whether SK hynix would build a chip plant in Japan. It set a 6:00 p.m. deadline, and the company replied at 4:03 p.m.

Each August answer promised an update “within one month.” The September updates each set a new three-month deadline.

ReportFirst filingLatest filingFiling typeNext re-disclosure date
Solidigm ₩5T pre-IPOAug 5, 2026Sept 4, 2026Voluntary clarificationDec 3, 2026
Chongqing plant stake sale (₩4T)Aug 10, 2026Sept 9, 2026Answer to KRX inquiryDec 8, 2026
Japan fabAug 21, 2026Sept 18, 2026Answer to KRX inquiryDec 17, 2026

Source: FSS DART. Status of all three: “unconfirmed” (mi-hwakjeong).

Timeline: Aug 5 Solidigm clarification, Aug 10 Chongqing answer, Aug 21 Japan answer, Sept 4, 9 and 18 updates, and re-disclosure deadlines on Dec 3, Dec 8 and Dec 17, 2026.
Each August answer promised news within a month; the September updates pushed the deadlines to December. Source: FSS DART filings, Aug 5 – Sept 18, 2026.

What each filing actually says

Quotes below are our translations of the Korean DART text. SK hynix’s 6-K English differs slightly.

Japan fab (20260918800583). The subject line refers to the report headlined “SK hynix to build a semiconductor plant in Japan.” The body says, in translation: “To strengthen the competitiveness of our memory business, we are reviewing various options, including building additional production bases, but nothing has been confirmed so far.” The answer itself does not mention Japan, a site, a partner or an amount. Korea JoongAng Daily wrote that the underlying reports placed the plant in Miyagi Prefecture, with an investment of tens of trillions of won. Speaking in Sendai on Aug 30, SK Group Chairman Chey Tae-won said the idea was still being studied (Korea Times).

Chongqing (20260909800559). The subject names the report on a stake sale at the “₩4 trillion” Chongqing plant. The answer frames the review around the packaging business: “We are reviewing various options to strengthen the competitiveness of our package business, but nothing has been confirmed so far.” This matches SK hynix’s July prospectus, which describes Chongqing as an assembly and testing site for back-end processing, not a wafer fab. According to Bloomberg, as cited by Korea JoongAng Daily, the plant was valued at about $3 billion.

Solidigm (20260904800642). This is a different form: a clarification of a press report, not an answer to an exchange inquiry. It names the Korea Economic Daily article of Aug 5, 2026, “SK hynix US subsidiary Solidigm pursues ₩5 trillion-scale pre-IPO.” It says, in translation, that Solidigm, “an overseas subsidiary of the company, is reviewing various options to strengthen its competitiveness, but nothing has been confirmed so far.”

The reported deal sizes differ. The DART filing quotes a ₩5 trillion headline. KED Global, the newspaper’s English edition, reported on Aug 5 that Solidigm was seeking up to ₩10 trillion (about $7 billion by KED’s conversion) at a valuation of about ₩50 trillion.

All three are signed off by head of finance Kim Woo-hyun and promise a new filing when details are confirmed or within three months.

Flow diagram: press report, exchange inquiry or clarification, a DART answer saying nothing is confirmed, then a deadline ending in a confirmed filing or another unconfirmed answer.
All three SK hynix filings sit at the "answer" stage, with deadlines in December. Source: FSS DART filings 20260904800642, 20260909800559 and 20260918800583.

The Intel statement and the Sept 28 share move (context)

On Sept 16, Reuters reported that SK hynix and Intel were in talks about US memory production. According to the Korea Herald’s summary, the options were leasing part of Intel’s Ohio site or forming a joint venture with Intel and cloud companies. SK hynix answered the same day in a newsroom statement, not a DART filing: it is “exploring various options,” and nothing is finalized, including cooperation with the companies named. Reuters, as carried by the Korea Herald, quoted the company citing “additional production bases,” the same phrase SK hynix used in its Japan filings of Aug 21 and Sept 18. That filing, though, formally answers only the Japan inquiry.

On Sept 28, the first trading day after the Chuseok holiday, SBS and FinanceFeeds reported that SK hynix closed down 5.05% at ₩1,768,000. SBS said foreigners net sold ₩1.7275 trillion of the stock and linked the fall to holiday-period global moves and concern about a Solidigm IPO. On Sept 25 (U.S. time), Reuters had reported that Solidigm was weighing a US IPO as early as next year, at a valuation of up to $150 billion. As of Sept 29, the Sept 4 clarification was still SK hynix’s latest DART filing on Solidigm.

Background for international holders

  • The ADS. According to the Form 424(b)(4) prospectus dated July 9, 2026, each SKHY American depositary share represents one-tenth of a common share. The IPO price was $149 per ADS, and Citibank, N.A. is the depositary. A July 13 DART filing says the ADSs listed on the Nasdaq Global Select Market on July 10, 2026 (Korea time). See our Korean ADR tickers list and ADR glossary entry.
  • Where filings appear. The prospectus says SK hynix, as a foreign private issuer, files Form 6-K for information it makes public under Korean law. All three 6-Ks carried the same dates as the Korean originals on DART.
  • Timing. The Aug 21 inquiry went out at 11:35 a.m. KST, or 10:35 p.m. on Aug 20 in New York, so answers can land before US markets open. See Korea stock market hours.
  • Solidigm’s origin. The prospectus says SK hynix paid Intel $6.6 billion in December 2021 and $2.2 billion in March 2025 for the NAND business that operates as Solidigm.
  • Currency. At ₩1,365.1 per dollar (Sept 28, per FinanceFeeds), ₩4 trillion is about $2.9 billion and ₩5 trillion about $3.7 billion.
Four fact cards: each SKHY ADS is one-tenth of a common share, the IPO price was $149 per ADS, SK hynix paid Intel $6.6 billion and $2.2 billion for Solidigm, and English filings appear on Form 6-K.
What international holders need to map DART filings to the Nasdaq-listed ADS. Source: SK hynix Form 424(b)(4) prospectus, July 9, 2026 (SEC EDGAR).

What to watch

  1. Dec 3, Dec 8 and Dec 17, 2026. An update can come earlier if details are confirmed. It may repeat “unconfirmed,” as in September, or confirm or drop a plan.
  2. A matching 6-K on EDGAR (CIK 2120882).
  3. Different filing types. Committed plant spending has appeared under a separate title; DART lists two “new facility investment” filings from SK hynix on Aug 7, 2026.
  4. Any new KRX inquiry. The Sept 25 Solidigm IPO report and the Intel talks have not triggered a DART filing so far.

What could go right / What could go wrong

What could go right: A confirmed filing would replace press reports with company terms: size, partner, timing and structure. For a Solidigm fundraising or a Chongqing sale, that could make clear how value would flow to the parent company.

What could go wrong: “Unconfirmed” can be repeated, which extends the uncertainty past December. SBS’s Sept 28 report cited concern about how a possible Solidigm IPO could affect SK hynix shareholders. The prospectus also warns that ADS and KRX prices can diverge. Reported deal sizes already differ between outlets, for example ₩5 trillion versus up to ₩10 trillion for Solidigm. Final terms, if any, may match neither figure.

More coverage: the SK hynix company hub and the Korea section.

FAQ

Q Is SK hynix building a fab in Japan?

A Not confirmed. In its Sept 18, 2026 DART filing, SK hynix said it is reviewing options, including additional production bases, and that nothing has been confirmed. It will update by Dec 17, 2026.

Q Is SK hynix selling its Chongqing plant?

A Not confirmed. SK hynix's Sept 9, 2026 answer to a Korea Exchange inquiry says it is reviewing ways to strengthen its packaging business and nothing is decided. The next update is due by Dec 8, 2026.

Q Is Solidigm doing an IPO?

A SK hynix's latest filing, dated Sept 4, 2026, says Solidigm is reviewing options and nothing has been confirmed. The next update is due by Dec 3, 2026. Reuters reported on Sept 25 that an IPO valuing Solidigm at up to $150 billion was under consideration.

Q Do SKHY ADR holders get these disclosures in English?

A Yes. SK hynix filed Form 6-K reports on SEC EDGAR with English versions on the same dates as the Korean DART filings (Sept 4, 9 and 18, 2026).

Companies in this report: SK hynix

Sources

  1. Response to KRX inquiry on Japan fab report, unconfirmed (Sep 18, 2026) — FSS DART (primary source)
  2. Response to KRX inquiry on Chongqing plant stake sale report, unconfirmed (Sep 9, 2026) — FSS DART (primary source)
  3. Clarification of Solidigm pre-IPO report, unconfirmed (Sep 4, 2026) — FSS DART (primary source)
  4. KRX inquiry on Japan fab report (Aug 21, 2026) — FSS DART (primary source)
  5. First response on Japan fab report (Aug 21, 2026) — FSS DART (primary source)
  6. First response on Chongqing report (Aug 10, 2026) — FSS DART (primary source)
  7. First clarification on Solidigm report (Aug 5, 2026) — FSS DART (primary source)
  8. Report on overseas listing of shares (ADS listing, Jul 13, 2026) — FSS DART (primary source)
  9. Prospectus, Form 424(b)(4) (Jul 9, 2026) — SEC EDGAR (primary source)
  10. Form 6-K: Response to Disclosure Inquiry, Japan (Sep 18, 2026) — SEC EDGAR (primary source)
  11. Form 6-K: Response to Disclosure Inquiry, Chongqing (Sep 9, 2026) — SEC EDGAR (primary source)
  12. Form 6-K: Clarification, Solidigm (Sep 4, 2026) — SEC EDGAR (primary source)
  13. No plans have been confirmed regarding the reported talks between SK hynix and Intel (Sep 16, 2026) — SK hynix Newsroom (primary source)
  14. SK hynix weighs stake sale in China packaging plant: report — Korea JoongAng Daily
  15. SK hynix weighs joint memory plant in Japan as part of overseas expansion efforts — Korea JoongAng Daily
  16. SK hynix still reviewing feasibility of Japan semiconductor plant — The Korea Times
  17. SK Hynix-owned Solidigm seeks up to $7 bn in pre-IPO share sale — KED Global
  18. SK hynix in talks with Intel over US memory production: Reuters — The Korea Herald
  19. SK hynix's Solidigm weighs IPO that could value unit at up to $150 billion, sources say — Reuters via The Korea Times
  20. Samsung Electronics and SK Hynix Plunge Over 5% — SBS
  21. KOSPI Breaks Below 7,000 as Samsung and SK Hynix Slide 5% After Chuseok — FinanceFeeds

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