#美光市值突破1万亿美元 1. Background of the Event and Market Performance: A Chip Bonanza Accelerates, Nasdaq and S&P Break Historic Lows Again

On May 27 (U.S. time May 26), the Nasdaq Composite Index and the S&P 500 Index refreshed their historic closing records again, supported by the dual impetus of easing U.S.-China tariffs and optimism about peace between the U.S. and Iran. The core driving force behind the index rally came from a five-day winning streak in the semiconductor sector, with memory-chip leader Micron Technology (Micron) becoming the undisputed star of the evening: its stock surged nearly 20%, and its market capitalization historically broke through the $1 trillion integer threshold, placing it strongly into the U.S. stock “trillion-dollar club.”

This is not a standalone one-day frenzy, but a continuation of a months-long structural revaluation of U.S. tech stocks. Over the past year, the market’s pursuit of AI computing power has gradually shifted from GPU manufacturers downstream to the entire industrial chain, including storage, packaging, and cooling. Starting from early 2025, Micron’s cumulative stock gain has nearly reached 10x, making it the most representative validation target in this storage supercycle.

In addition to Micron, other companies that delivered standout performance that night included: SanDisk, which surged by more than 11%, continuing the full-year storage-chip rally; and Qualcomm, which rose by nearly 8%, after having already gained more than 20% over the prior week, indicating a broad-based rally rather than an isolated move by a single stock.

2. Breakdown of Core Driving Factors: Accelerated Revaluation Under the Resonance of Three Logic Threads

1. AI Computing-Power Demand Evolves from “GPU Shortage” to “Memory Shortage,” with HBM Logic Continuing to Be Delivered

The current bottleneck in AI large-model training computing power has shifted from Nvidia’s GPU supply to high-bandwidth memory chips (HBM). Micron is one of the three largest HBM suppliers globally, and its entire HBM production capacity for 2026 has already been sold out, pointing to a severe supply-demand imbalance that suggests prices will likely keep strengthening. From an investment framework perspective, the focal point for building AI infrastructure is undergoing a structural shift: as GPU cluster sizes expand exponentially, the marginal constraint from storage bandwidth is replacing raw computing power itself as the system bottleneck. Previously, the market’s valuation logic for Micron still rested on the “cyclical stock” paradigm—DRAM prices under pressure when PC and smartphone demand are weak—but AI data-center-driven HBM demand is fundamentally reshaping its valuation framework.

2. A Material Change in Storage Industry Fundamentals: The LTA Framework Rebuilds the Pricing Model

Micron’s near-20% surge this time had a direct catalyst: on May 26, UBS raised Micron’s target price from 535 USD to 1625 USD, more than tripling (a gain of over three times). It is important to emphasize that UBS’s upgrade logic is not limited to traditional supply-demand analysis; it focuses on a more institutionally meaningful industry shift—storage companies are rolling out enhanced long-term supply agreements for the first time.

This new business model breaks the old framework in which storage chips were simply locked to shipment volume, with prices moving in line with the market. The new LTA introduces partial fixed-pricing provisions, and contract terms are generally extended to 3 to 5 years, typically split into two categories: “2+3 mode” (two years of fixed-price terms plus three years of variable-price terms) and “3+2 mode.” For Micron, this mechanism is the pivot for valuation re-anchoring: visibility into gross margin improves significantly, and the “cyclical stock” label is being replaced by a valuation logic of “infrastructure-like deterministic assets.” Based on this, UBS predicts that within 12 months, Micron’s market capitalization could expand to 1.8 trillion USD, implying there is still nearly 80% upside potential.

3. Geopolitical “Peace Expectations”: An Amplifier of the Market’s Excess Premium

Besides strong support from industry fundamentals, the market’s macro sentiment is also an impulse that cannot be ignored. Around May 26, several phased easing signals emerged in U.S.-Iran relations. In the mid-to-late May period, Trump repeatedly released signals via social media such as “a peace agreement is close to being reached” and “the Strait of Hormuz may reopen.” Although the details of negotiations and actual progress remain highly uncertain, these statements at sensitive times provided a notable marginal lift to market risk appetite.

The semiconductor industry is one of the global supply-chain segments most deeply affected by geopolitics. Expectations of easing U.S.-Iran relations directly feed into assessments of oil prices and the stability of global shipping corridors, thereby reducing the geopolitical risk premium embedded in broad asset pricing. When the AI sector already had strong bullish sentiment accumulating, improvements in the surrounding geopolitical outlook were like “adding another scoop of fuel to an already blazing furnace.”

3. Key Stock Performance and Investment Logic

Micron Technology: The Fastest Route to a Trillion-Dollar Valuation, and the Valuation Repricing Is Not Over Yet

Micron moved from a 500 billion USD market cap to surpassing the trillion-dollar threshold in just 48 days, setting a record for the fastest crossing from the 500 billion USD to the 1 trillion USD range in U.S. stock market history. This climb speed carries strong signaling value: it suggests that the market’s valuation logic for memory-chip companies is switching from “cyclical discount” to “AI infrastructure premium” at an astonishing pace.

So far this year, Micron has set 28 new closing-price record highs, a frequency that is rare even among U.S. tech leaders.

SanDisk: A Supercycle Winner Returning to Public Markets

Since SanDisk spun off from Western Digital and returned to public markets in February 2025, its stock has accumulated a gain of 580%, becoming the best-performing individual stock among S&P 500 constituents for the year. Its surge is not driven by a single catalyst, but by a deep resonance between “passive buying triggered by index inclusion” and “fundamental revaluation under the storage supercycle.” The Nasdaq previously announced that it would include SanDisk in the Nasdaq 100, which objectively triggered large-scale ETF passive rebalancing purchases, further magnifying the upward momentum in the share price. At the same time, management’s remarks about “restrained supply growth through 2026” continue to reinforce the market’s confidence in a NAND industry environment characterized by supply constraints relative to demand.

Qualcomm: A Differentiated Bet on Edge AI

Qualcomm’s logic for rising by nearly 8% this time differs somewhat from Micron and SanDisk; its core driver comes from the acceleration of AI deployment at the consumer electronics side (edge). In May 2025, Qualcomm signed a multi-year cooperation agreement with Xiaomi covering smartphones, automobiles, AR/VR, and other areas, and Xiaomi confirmed that the first batch will adopt the next-generation Snapdragon 8 series platform. Earlier in May, Qualcomm’s single-day gain had already exceeded 10%, briefly refreshing a phase high, indicating the market’s strong expectations for edge AI penetration in the second half of 2025 through 2026.

Compared with storage-chip makers who benefit from AI infrastructure build-out on the training side, Qualcomm’s rally places greater emphasis on the long-term narrative of AI applications extending from cloud to the edge—giving it a certain degree of differentiation within the current segment.

4. Summary and Outlook

On May 27, Micron’s market cap broke through the trillion-dollar mark, and SanDisk and Qualcomm both surged in tandem, while the Nasdaq and S&P once again hit new highs. A series of these market phenomena point to a trend that is effectively irreversible: AI capital expenditures are systematically reshaping the valuation framework across the entire semiconductor industry, and the process of switching from “cyclical logic” to “growth logic” has only just entered an accelerated phase.

Of course, risks should not be ignored. The current valuation levels for memory chips have already moved away from traditional historical ranges, and any signal of supply expansion beyond expectations or a slowdown in AI capital spending could trigger sharp fluctuations. At this stage, the logic for investing in the memory/storage sector should not rely solely on belief in the “AI story”; it is also necessary to stay tightly focused on hard fundamentals such as HBM capacity progress, the cadence of LTA signings, and customer order visibility in order to assess the risk-reward ratio.