Kioxia Holdings - Company History

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Financial history 2022–2026 — revenue, cost structure, balance sheet, cash flow and key ratios, year by year →

Founded 2019
Founder None — carved out of Toshiba Corporation
Founding location 東京都港区
Core business at founding NAND flash memory
Listed 2024
President Ota Hiroo President since 2026 (age 63, as of 2026)
Current priority Capacity investment Raising output of SSDs for AI and data centres
Founding
The real founding of the semiconductor business was January 1951, when the parent company Toshiba (Tokyo Shibaura Electric) built a prototype transistor at its Komukai works in Kawasaki. In 1987 Masuoka Fujio and his colleagues presented the world's first NAND flash memory, but the invention did not translate at once into a business advantage, and turning it into earnings was a struggle. Concentrated production began at the Yokkaichi plant in 1999 and grew into a high-margin business; then Toshiba, cornered by an accounting scandal and the collapse of its nuclear business in the United States, decided in 2017 to carve the NAND operation out, and sold it to the Bain Capital consortium for about $18.1B (¥2tn). In October 2019 the group was renamed Kioxia and the present company came into being. That sale also shows how far Toshiba had been driven — it had to cut loose its most profitable business.
The Decision
It never broke the concentration of investment on a single product, even as the owner changed. A joint venture with SanDisk of the United States began in 2000, and when Toshiba withdrew from commodity DRAM in 2001 to concentrate on NAND, Yokkaichi turned into a site dedicated to NAND alone. The three-dimensional technology developed in 2007 was commercialised as BiCS FLASH, and resources were concentrated on winning capacity by stacking rather than by shrinking a planar cell. The capital side, meanwhile, kept moving: the carve-out and sale of 2017 put the business under a foreign fund, and in December 2024 the listing was achieved after four years of trying. Through the passage of ownership from Toshiba to an investment fund and then to the market, the destination of its investment never changed, and that is what has kept it in the shape of a specialist maker.
Today
Kioxia works exclusively on NAND flash memory and SSDs, and earns close to nine-tenths of its revenue outside Japan. Of revenue of $14.8B (¥2.34tn) in the year to March 2026, Japan accounted for $1.7B (¥263bn), Europe and the Americas for $7.7B (¥1.22tn) and Asia for $5.4B (¥857bn), with high-capacity SSDs for generative AI and data centres the main driver of the increase. Operating profit of $5.5B (¥870bn) and net profit of $3.5B (¥555bn) were both records, and operating profit passed the level of the year to March 2018, in the Toshiba Memory era. Bain sold the last of its holding in July 2026, eight years in, and Toshiba — which had sold the business in the first place — is back as the effective largest shareholder with 17.59 per cent. The company that let the business go now stands as a shareholder receiving the record profits that followed.
Competition
This is a market in which Kioxia, having invented it, never took first place. NAND flash memory was a technology it brought into the world itself, yet it fell behind on the scale of investment and handed the crown to the company it had licensed. It now contests second place behind the leader, Samsung Electronics. With Western Digital, which splits production with it at Yokkaichi and Kitakami, it negotiated a merger from 2021, but the shape of the share register — with the rival SK Hynix on it — blocked the deal. In a market that demands hundreds of billions of yen of capital spending at every generation, a difference in scale becomes directly a difference in the capacity to fund the next round of investment.

Timeline

1951–1999From transistors to the top of 1-megabit DRAM, and the invention of NAND flash

  1. 1951Tokyo Shibaura Electric prototypes a transistor at Komukai, Kawasaki
  2. 1956Among the first five Japanese firms licensed for transistors by Bell Labs and Western Electric
  3. 1981Kawanishi Tsuyoshi takes over the semiconductor division amid reports of a DRAM exit
  4. 1984Masuoka Fujio presents a single-transistor memory cell at IEDM
  5. 19861-megabit DRAM output reaches a million units a month; world leadership in the category
  6. 1986The US–Japan Semiconductor Agreement is signed on 2 September
  7. 1987Toshiba presents the world's first NAND flash memory at IEDM
  8. 1991The world's first 4-megabit NAND flash memory goes into volume production
  9. 1992The Yokkaichi plant is established in Mie prefecture
  10. 1992NAND technology is licensed to Samsung Electronics
  11. 1994Masuoka leaves Toshiba for a professorship at Tohoku University
  12. 1999Yokkaichi begins NAND production as flash supply tightens

2000–2016Out of commodity DRAM, into the SanDisk joint ventures, and the turn to three dimensions

  1. 2000Collaboration with the SanDisk group on flash memory begins (May)
  2. 2001Toshiba decides to exit commodity DRAM and sells the Dominion fab to Micron (December)
  3. 2002Flash Vision, the first SanDisk joint venture, is set up for Yokkaichi (April)
  4. 2005Fab 3 starts up on 300-millimetre wafers (February)
  5. 2007Three-dimensional flash memory technology is developed (June)
  6. 2007Fab 4 is completed and runs volume production at 43 nanometres (September)
  7. 2008Toshiba raises its equipment stake in Fabs 3 and 4 to 65 per cent for $1bn
  8. 2011The Semiconductor & Storage Products in-house company is created (July)
  9. 2014Volume production of 15-nanometre 128-gigabit NAND (April)
  10. 201548-layer BiCS FLASH samples begin shipping (March)
  11. 2016Western Digital acquires SanDisk, changing the Yokkaichi partner (May)
  12. 201664-layer BiCS FLASH samples begin shipping (July)

2017–2019Toshiba's crisis, the carve-out and sale, and the birth of Kioxia under the Bain consortium

  1. 2015An investigation committee finds operating profit overstated; the president resigns
  2. 2017The former Toshiba Memory Corporation is incorporated (February)
  3. 2017Westinghouse files under Chapter 11 on 29 March
  4. 2017Memory and SSD operations are transferred from Toshiba by corporate split (1 April)
  5. 2017The Bain-led Japan–US–Korea consortium is chosen as preferred bidder (June)
  6. 2017A share transfer agreement is signed with Pangea (28 September)
  7. 2017The Western Digital arbitration is settled (13 December)
  8. 2018Toshiba transfers all shares to Pangea for about ¥2tn (1 June)
  9. 2018Pangea absorbs the former Toshiba Memory and takes its name (August)
  10. 2018Fab 6 and the Memory R&D Center are completed at Yokkaichi (September)
  11. 2019Toshiba Memory Holdings is created by share transfer (1 March)
  12. 2019The group is renamed Kioxia (1 October)
  13. 2019Fab 1 at the Kitakami plant in Iwate is completed (October)

2020–2026A listing that outlasted a collapsed merger, and the climb to record profits

  1. 2020The listing planned for 6 October is postponed on 28 September
  2. 2020All shares in LITE-ON's SSD subsidiary SSSTC and its affiliates are acquired (July)
  3. 2021Western Digital proposes a merger by share exchange worth about $20bn
  4. 2022Fab 7 at the Yokkaichi plant is completed (October)
  5. 2023Prototypes of the eighth-generation 218-layer BiCS FLASH (March)
  6. 2023The Western Digital merger talks collapse (October)
  7. 2024The building for Fab 2 at the Kitakami plant is finished (July)
  8. 2024A second listing attempt is shelved in late September
  9. 2024Kioxia lists on the TSE Prime Market under code 285A (18 December)
  10. 2025Fab 2 at Kitakami starts operating (September)
  11. 2026Record revenue, operating profit and net profit for the year to March
  12. 2026Bain Capital sells its final stake and exits after eight years (July)

Founding Story

1951–1999From transistors to the top of 1-megabit DRAM, and the invention of NAND flash

Kioxia's history does not begin with Kioxia. Every element of it — the fab at Yokkaichi, the NAND cell architecture, the habit of investing a generation ahead of the market — was assembled inside Toshiba across the second half of the twentieth century by an operation that climbed to world leadership in 1-megabit DRAM and then invented the memory that would outlive DRAM. What Toshiba could not do in the same decades was convert either achievement into a durable lead of its own.

A transistor prototype, and the climb to world leadership in DRAM

Kioxia's NAND flash memory business was separated out of the semiconductor operation of its parent, Toshiba (Tokyo Shibaura Electric)[1]. In January 1951 Tokyo Shibaura Electric built a prototype transistor at its Komukai works in Kawasaki[2]. By July 1956 it was one of the first five Japanese companies — alongside Tokyo Tsushin Kogyo (later Sony), Hitachi, Mitsubishi Electric and Kobe Kogyo — to take a licence for transistor technology from Bell Laboratories and Western Electric in the United States[3]. In memory, however, Toshiba trailed behind NEC and Hitachi[4]. Through the period spanning the second oil crisis it held back capital spending and shrank the scale of the business[5], and shortly after Kawanishi Tsuyoshi (川西剛) took charge of the semiconductor division in 1981, newspapers reported that Toshiba would withdraw from DRAM altogether[6].

Toshiba reached the top of the 1-megabit DRAM market[7] because it chose a different road from its rivals on both technology and investment. The denser a DRAM becomes, the more it demands three-dimensional processing — digging trenches down or stacking cells up[8] — but at the 1-megabit generation Toshiba chose a planar cell and low-power CMOS[9], cutting power consumption to less than half the previous level and taking the advantage in manufacturability. While the other makers were shifting production from 64 kilobits to 256 kilobits, Toshiba invested ahead straight into 1 megabit[10], raised output to a million units a month in 1986, and became the world leader in that product category[11]. In the same year Japan's semiconductor share overtook that of the United States, with Toshiba ranked among the leaders alongside NEC and Hitachi[12]. On 2 September the US–Japan Semiconductor Agreement was signed[13], restricting sales below fair market value. When the COCOM violation case at Toshiba Machine threatened to shut Toshiba out of the American market, IBM and Hewlett-Packard — both dependent on its 1-megabit DRAM — lobbied Congress, and the sanctions were confined to exclusion from US government procurement[14].

Masuoka Fujio's invention, and the name Toshiba gave it — flash memory

NAND flash memory, Kioxia's principal product, was invented by a Toshiba engineer[15]. In 1980 Masuoka Fujio (舛岡富士雄) began work on non-volatile memory with a handful of engineers at Toshiba's research site in Kawasaki[16], and at the IEDM international conference in 1984 he presented a compact memory whose storage element was built from a single transistor[17]. Its area per bit was less than a quarter that of a conventional EEPROM[18], and because the whole array could be erased at once and quickly — in a way that brought a camera flash to mind — his colleague Ariizumi Shoji (有泉章二) gave it the name flash[19]. Against that scheme, later called NOR, Masuoka devised a NAND arrangement that wired the elements together in series to raise storage capacity per unit of area[20]. Toshiba presented it to the world for the first time at IEDM in 1987[21]. The aim was to replace the hard disk drive in personal computers with semiconductors[22].

Toshiba commercialised the world's first 4-megabit NAND flash memory in 1991[23] and set up the Yokkaichi plant in Mie prefecture in 1992[24]. It was slower, however, at turning the invention into a business: as of 1991 Toshiba's development staff still numbered only a few dozen[25]. Intel, which had created a dedicated division in 1986 and staffed it in the hundreds, held more than 85 per cent of the world flash memory market by 1992[26]. In that same year Toshiba licensed its NAND technology to Samsung Electronics of South Korea[27]. In 1992, with the Japanese makers holding back investment through the semiconductor downturn, Samsung committed to an eight-inch volume production line, and that investment carried it to world leadership in DRAM[28]. Dissatisfied with his treatment, Masuoka left Toshiba in 1994 to become a professor at Tohoku University[29]; his suit for compensation for the invention was settled in 2006[30]. Toshiba could not sustain its competitiveness in DRAM at the 16-megabit generation[31], and by 1999, when Yokkaichi began producing NAND[32], the spread of mobile phones and digital cameras had left flash memory in tight supply[33].

Read the full history in Japanese →

Notes

  1. Kioxia, History of Our Memory, October 2019↩
  2. Monument marking the birthplace of the Toshiba transistor, erected 1960↩
  3. Semiconductor History Museum of Japan (SHMJ)↩
  4. 日経ビジネス (Nikkei Business), 16 December 1991↩
  5. 日経ビジネス (Nikkei Business), 1 July 1991↩
  6. 日経ビジネス (Nikkei Business), 1 July 1991↩
  7. Semiconductor History Museum of Japan — Shimura Yukio, 日本半導体興亡史 (A History of the Rise and Fall of Japanese Semiconductors)↩
  8. 日経ビジネス (Nikkei Business), 4 December 1989↩
  9. Semiconductor History Museum of Japan — Shimura Yukio, 日本半導体興亡史 (A History of the Rise and Fall of Japanese Semiconductors)↩
  10. 日経ビジネス (Nikkei Business), 16 December 1991↩
  11. Semiconductor History Museum of Japan — Shimura Yukio, 日本半導体興亡史 (A History of the Rise and Fall of Japanese Semiconductors)↩
  12. Semiconductor History Museum of Japan↩
  13. Semiconductor History Museum of Japan; text of the US–Japan Semiconductor Agreement of 2 September 1986↩
  14. 日経ビジネス (Nikkei Business), 1 July 1991↩
  15. IEEE Spectrum, Chip Hall of Fame: Toshiba NAND Flash Memory↩
  16. IEEE Spectrum, Chip Hall of Fame: Toshiba NAND Flash Memory↩
  17. IEEE Spectrum, Chip Hall of Fame: Toshiba NAND Flash Memory↩
  18. Computer History Museum, Pioneers of Semiconductor Non-Volatile Memory (NVM)↩
  19. Kioxia, History of Our Memory, October 2019↩
  20. IEEE Spectrum, Chip Hall of Fame: Toshiba NAND Flash Memory↩
  21. Kioxia, History of Our Memory, October 2019↩
  22. 日経ビジネス (Nikkei Business), 26 January 1998↩
  23. Kioxia, History of Our Memory, October 2019↩
  24. Kioxia, History of the Yokkaichi Plant, official website↩
  25. 日経ビジネス (Nikkei Business), 22 July 1991↩
  26. 日経ビジネス (Nikkei Business), 22 July 1991, and 8 June 1992↩
  27. IEEE Spectrum, Chip Hall of Fame: Toshiba NAND Flash Memory↩
  28. 日経ビジネス (Nikkei Business), 11 November 1996↩
  29. IEEE Spectrum, Chip Hall of Fame: Toshiba NAND Flash Memory↩
  30. IEEE Spectrum, Chip Hall of Fame: Toshiba NAND Flash Memory↩
  31. 証券アナリストジャーナル (Securities Analysts Journal), September 1998 supplement, Toshiba — lecture of 3 August 1998↩
  32. Kioxia, History of the Yokkaichi Plant, official website↩
  33. 日経ビジネス (Nikkei Business), 23 August 1999↩

References & sources

  1. Kioxia — official account of the invention and naming of flash memory. History of Our Memory.
  2. Kioxia — chronology of the Yokkaichi plant,. Kioxia.
  3. F. Masuoka, M. Momodomi, Y. Iwata, R. Shirota — New ultra high density EPROM and flash EEPROM with NAND structure cell, IEDM 1987. IEEE Xplore.
  4. IEEE Spectrum — Chip Hall of Fame: Toshiba NAND Flash Memory. IEEE Spectrum.
  5. Computer History Museum — pioneers of semiconductor non-volatile memory, the first four decades. CHM.
  6. Semiconductor History Museum of Japan (1-megabit DRAM leadership; the US–Japan Semiconductor Agreement). SHMJ.
  7. Toshiba Corporation — IR releases: notice on the Westinghouse Chapter 11 filing, 29 March 2017; notice regarding closing of the memory business transfer, 1 June 2018. Toshiba.
  8. EE Times — Toshiba exits the DRAM market and sells its Virginia fab to Micron, 2001. EE Times.
  9. CNBC, Bloomberg, Fortune — reporting on the 2015 accounting investigation and the 2017 sale process. CNBC.

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Data API

Kioxia Holdings’s history, presidents and financials are published as static JSON — no key, plain GET. One API per public page, and one per section where a page carries several tables. Full specification →

/api/285A/company.json ·/api/285A/history.json ·/api/285A/ceo.json ·/api/285A/financials.json ·/api/285A/financials/segment.json ·/api/285A/financials/pl.json ·/api/285A/financials/cf.json ·/api/285A/financials/bs.json ·/api/285A/financials/employee.json ·/api/285A/financials/stock.json ·/api/285A/financials.csv ·/api/285A/financials_history.csv

/api/companies.json ·/api/decisions.json ·/api/api-manifest.json