SK hynix poured 12.3488 trillion won into capital expenditures in the fourth quarter alone last year. Its full-year capex totaled 30.173 trillion won, about 40% of which was executed in the fourth quarter. The industry says the company executed large-scale investments to retake market leadership as competition in high bandwidth memory (HBM) intensified with Samsung Electronics and Micron. SK hynix signaled that this expansionary capex stance will continue this year.
According to the Financial Supervisory Service's electronic disclosure system on the 2nd, SK hynix invested an amount equivalent to 31.1% of last year's annual revenue (97.1467 trillion won) in capex. That was a 68.0% surge compared with 2024 capex (17.956 trillion won). Until the third quarter last year, quarterly capex stayed around the 5 trillion–6 trillion won level, but in the fourth quarter it topped 12 trillion won, a notable change.
◇ Market leadership wavers for the "No. 1 in HBM" corporations
The semiconductor industry notes that the timing of SK hynix's aggressive capex ramp-up coincided with when its "HBM market leadership" began to waver. SK hynix effectively maintained a position as Nvidia's exclusive supplier through fifth-generation HBM (HBM3E). Samsung Electronics and Micron also supplied HBM3E to Nvidia, but SK hynix's shipment volume was overwhelmingly larger.
That structure began to crack in the second half of last year. Samsung Electronics started increasing shipments to major customers such as Nvidia, and that trend appears to be continuing into the next-generation products.
In the semiconductor industry, the assessment is that Samsung Electronics seized market leadership from SK hynix by announcing the "world's first mass-production shipments" of sixth-generation HBM (HBM4). HBM4 is mounted on the "Vera Rubin" artificial intelligence (AI) chip that Nvidia is launching this year. In effect, it designed an HBM4 that meets Nvidia's requirements ahead of SK hynix and began mass production. Samsung Electronics also showcased physical seventh-generation HBM (HBM4E) last month at Nvidia's annual developer conference, GTC 2026, signaling confidence in its technology.
The chase by Micron, the No. 3 memory semiconductor corporations, is no pushover. Micron officially announced mass-production shipments of HBM4 to coincide with the opening of GTC 2026. Some had speculated that Micron was excluded from the initial Vera Rubin supply, but Micron said its mass-shipped HBM4 was "designed for Vera Rubin."
By contrast, SK hynix announced in September last year that it had established the industry's first mass-production system for HBM4, but it has yet to report shipments. An industry source familiar with SK hynix's situation said, "My understanding is that design changes to meet Nvidia's requirements have not yet been completed."
◇ Betting big on capex to secure competitiveness
It is plausible that SK hynix's large capex increase was intended to respond to these market changes. With HBM market competition growing even fiercer this year, the semiconductor industry says SK hynix may continue its expansionary capex stance. In fact, SK hynix also said in last year's annual results materials, "We expect this year's investment scale to increase significantly from the previous year."
Signs of SK hynix's capex expansion have been steadily observed since early this year. On Feb. 24, SK hynix's board approved the introduction of extreme ultraviolet (EUV) scanner equipment worth 11.9496 trillion won from ASML of the Netherlands. This includes amounts for new machinery, installation, and modifications for operations. The EUV expansion, to be carried out over about two years through Dec. 2027, is aimed at "responding to next-generation process mass production." The company added capacity to meet rising demand for AI memory, including HBM4, as well as expanding demand for commodity DRAM.
In February, it also announced an additional 21.6081 trillion won investment through the end of December 2030 to build Phase 1 fabs (production facilities) at the Yongin semiconductor cluster. As a result, the total investment for the Phase 1 fabs rose to 31 trillion won. The Phase 1 fab complex, being built to the height of a 50-story apartment building in Wonsam-myeon, Cheoin-gu, Yongin, Gyeonggi Province, will comprise two structural frames and six cleanrooms. SK hynix plans to open the cleanrooms early through the additional investment to meet customer demand. Recently, it also purchased one unit of a hybrid bonding inline tool co-developed by Applied Materials of the United States and Besi of the Netherlands, accelerating efforts to secure next-generation manufacturing capabilities.
It is also working to secure funding. SK hynix submitted a confidential public offering registration statement (Form F-1) to the U.S. Securities and Exchange Commission (SEC) on Feb. 24 for an American depository receipts (ADR) listing. ADRs are securities issued to allow foreign corporations to trade their shares on U.S. stock markets. They are mainly used to expand access for global investors. While the issuance size and method are not set, the market estimates about 10 trillion–15 trillion won. SK hynix President Kwak Noh-jung said at the 2026 shareholders meeting last month, "We are preparing with the goal of listing in the second half of this year," adding, "We will secure more than 100 trillion won in net cash."
SK hynix maintains a stance of spending around 30% of revenue on capex (capex discipline). According to financial data provider FnGuide, SK hynix's annual sales consensus (the average of securities firms' forecasts) for this year amounts to 238.5368 trillion won. If the capex ratio holds this year as well, capex could more than double from the previous year.
An industry official said, "SK hynix showed a conservative stance on equipment and facility investments after it secured HBM market leadership firmly," but added, "Since assessments emerged that its HBM market leadership was wavering, the mood has swung 180 degrees, and it is actively moving to secure production capacity."