New York, January 26, 2026, 16:55 EST — After-hours
- Micron dropped 2.6% to close at $389.09, hitting a low of $384.59 during the session
- Traders highlighted new reports on Samsung’s upcoming HBM4 memory roadmap for Nvidia
- Attention shifts to Samsung and SK Hynix earnings on Thursday, looking for insights into HBM4 demand
Shares of Micron Technology, Inc. (MU.O) dropped 2.6% on Monday, closing at $389.09. The slump followed news that Samsung Electronics is edging nearer to providing Nvidia with a new breed of top-tier memory chips.
The decline is significant since Micron’s recent gains have hinged on high-bandwidth memory, or HBM — stacked DRAM paired with AI processors to speed up data transfer and reduce power consumption. If a competitor starts securing qualification and production slots for the upcoming HBM cycle, it could shift investor expectations around growth and margins.
HBM remains a bottleneck trade. Just a few suppliers can deliver at scale, so even minor changes in who gets onboarded for the next platform can sway stocks. This is especially true ahead of earnings from Asia’s memory giants later this week.
Samsung is gearing up to begin production of its next-gen HBM chips, HBM4, starting next month, according to a source who spoke to Reuters on Monday. The Korea Economic Daily reported that Samsung passed HBM4 qualification tests for both Nvidia and AMD and will start shipping to Nvidia next month. Samsung declined to comment, and Nvidia was not immediately reachable. Nvidia CEO Jensen Huang has confirmed that the company’s Vera Rubin platform is already in “full production” and slated to debut later this year with HBM4. Reuters
In U.S. trading, Nvidia shares slipped around 0.7%, while AMD dropped about 3.3%. Semiconductor ETFs pulled back as well, with Micron standing out as one of the group’s bigger losers.
Samsung is ramping up efforts to challenge SK Hynix, which currently dominates as a supplier of advanced memory for Nvidia’s AI accelerators. Earlier this month, Samsung’s chip chief Jun Young-hyun claimed customers are saying “Samsung is back” on HBM4. According to Counterpoint Research data cited by Reuters, SK Hynix held a 53% share of the HBM market in Q3 2025, with Samsung at 35% and Micron trailing at 11%. Reuters
Micron stands as the third key player in the HBM market and is ramping up capacity. This month, it signed a letter of intent to acquire Powerchip’s P5 fab in Taiwan for $1.8 billion in cash. Production boosts are slated for the latter half of 2027. Micron CEO Sanjay Mehrotra has indicated that memory markets will stay tight beyond 2026.
Micron investors aren’t sweating demand just yet — Nvidia’s AI plans suggest each accelerator will need more memory. The real concern? What if another supplier gets through qualification and scales up quicker than anticipated, hitting pricing and market share hard.
HBM4 volumes, pricing, and customer allocations are still unclear, with the latest reports failing to reveal how many chips Samsung plans to supply. This lack of clarity could swing either way.
There’s a downside risk as well. If several suppliers ramp up production simultaneously, the memory market’s typical cycle could kick in and push prices down, even with strong AI demand. Conversely, tight supply combined with multi-sourcing might soften the blow from competitive news, making the initial market reaction less severe.
Thursday brings the next trigger, with Samsung and SK Hynix set to release their quarterly results. Investors will be watching closely for updates on HBM4 order schedules and volumes — details that could influence Micron’s trading throughout the week.
