Kioxia surged 9% on Friday, with the move accounting for 16% of the Nikkei’s rise that session.
- Kioxia Holdings Corporation (TYO:285A) finished at ¥83,300, up 9.23%. Shares moved between ¥67,190 and ¥84,390 during the session.
- The Nikkei 225 added 1,010.92 points. Kioxia’s price-adjusted move was about 165 points, or around 16% of the Nikkei’s gain, based on the index’s published divisor and Kioxia’s PAF.
- Kioxia and Sandisk Corporation NASDAQ:SNDK have kicked off production of their 10th-gen 3D flash at the Kitakami Fab2 plant. Kioxia is also sampling 1Tb TLC devices now.
Kioxia Holdings Corporation (TYO:285A) played a major role in Friday’s move for Japan’s main index. Shares were up 7,040 yen, which worked out to about 165 points for the Nikkei 225 using the 0.7 price-adjustment factor for Kioxia and the July 3 Nikkei divisor of 29.83110217. That made up roughly 16% of the Nikkei’s 1,010.92-point gain.
The stock opened at ¥68,000, dropped to ¥67,190, and finished the session at ¥83,300. That put the high-low range at ¥17,200, or 22.6% of the previous close as calculated from Friday’s move. Trading volume came in at 56.82 million shares, about 50% above the average on Google Finance.
Nikkei says its method changes the impact of the move. The index calculates with adjusted prices for its components and a divisor, and notes that high-priced tech names often drive price-weighted indexes. Kioxia has been in the Nikkei 225 since April 1.
| Friday close data | Close | 1-day move | Market read |
|---|---|---|---|
| Kioxia Holdings (TYO:285A) | ¥83,300 | +9.23% | Seen adding about 165 points to the Nikkei |
| Nikkei 225 | 69,744.07 | +1.47% | Up 1,010.92 points |
| Tokyo Electron (TYO:8035) | ¥73,200 | +0.36% | Missed the move in memory stocks |
| Advantest (TYO:6857) | ¥29,345 | +1.84% | Other chip-equipment name closed higher |
Google Finance and the Nikkei Indexes supplied Friday’s closing data.
Kioxia shares closed near session highs. The company and Sandisk said they had begun 10th-generation 3D Flash production at the Kitakami Plant Fab2 in Iwate Prefecture. Kioxia said it has also started sample shipments for 1Tb triple-level-cell memory, targeting enterprise and data-center SSDs.
| Kioxia 10th-generation BiCS Flash metric | Reported data | Why investors care |
|---|---|---|
| NAND interface speed | 4.8 Gb/s, 33% higher than 8th gen | SSDs move data faster |
| Bit density | Up 59%, now at 332 layers | More storage from each wafer |
| Power efficiency | Write up 18%, read up 30% | Better pitch on data-center costs |
| Target use | Enterprise and data-center SSDs | Tied to AI storage needs |
Investors will get a clear read on the AI storage trade from the numbers. If Kioxia ramps production but holds the line on NAND prices, the stock can keep drawing in both passive index flows and memory-cycle bets. But if supply ramps too fast, the high prices that boosted the Nikkei on Friday could turn into a headwind.
Satoru Oyama, a consultant and former Tokyo Electron employee, told Reuters that NAND investment has been pushed to the “back burner” for most chipmakers, with current demand focused mostly on Kioxia. Kazuyoshi Saito, analyst at IwaiCosmo Securities, said Kioxia leads rivals in NAND performance and power efficiency by two to four years. Reuters
Kioxia Iwate President and CEO Koichiro Shibayama said production of “advanced 10th-generation flash memory” had started at the Kitakami plant. Sandisk CTO Alper Ilkbahar called it an “important milestone.” Business Wire
Valuation is now a driver in the trade. Kioxia finished Friday at a market value of ¥45.59 trillion, according to Google Finance, which is higher than Tokyo Electron’s ¥34.26 trillion. Reuters said Kioxia’s market cap broke $250 billion after the stock jumped more than seven times so far this year, putting it above Toyota Motor (TYO:7203).
Supply remains the weak spot. SK Hynix KRX:000660 announced plans this week to invest 80 trillion won in a new NAND plant, according to Reuters. This is key for Kioxia, since memory shortfalls have tended to resolve when new capacity meets demand.
Kioxia has notified investors it’s working on a plan to list American depositary shares in the U.S., though it hasn’t set a timeline or picked an exchange. The company said it is still considering whether to lower investment units. Kioxia reports first-quarter FY2026 results on July 31 at 15:30 JST.
