Global Stock Market Today: AI-Led Tech Jitters Hit Asia, Europe Turns Cautious Before Central Banks, Micron Lifts U.S. Futures (Dec. 18, 2025)

Updated: 5:00 AM EST (10:00 GMT), Thursday, December 18, 2025

Global equities are starting December 18 on an uneasy footing, with investors reassessing the durability of the AI-fueled rally just as a dense run of central bank decisions and a closely watched U.S. inflation report approach.

Overnight, a tech-heavy retreat in the U.S. reverberated across Asia, while early European trading stayed muted with rate decisions due from the Bank of England and the European Central Bank (among others). In U.S. premarket trading, Micron’s strong outlook is helping stabilize sentiment, but markets remain tightly focused on inflation data and policy signals that could shape 2026 positioning. ^[1]

The big theme at 5:00 AM EST: “AI capex” anxiety meets central bank divergence

Two forces are dominating the global stock market today:

1) Tech and AI infrastructure doubts.
Investors are increasingly scrutinizing whether the massive spending required to build AI capacity will translate into profits—especially for companies taking on more debt to fund data centers, chips, and power-hungry infrastructure. That debate intensified after a sharp Wednesday selloff in major U.S. AI bellwethers. ^[2]

2) A wave of central bank decisions across regions.
Markets are bracing for policy divergence: the Bank of England is widely expected to cut rates, the ECB is expected to hold steady, and traders are also watching Japan closely for a potential rate hike. ^[3]

Asia markets: Tech drags, but China ends mixed

Asian equities broadly tracked Wall Street’s tech-led weakness, though the picture was uneven by the close.

Japan: The Nikkei fell about 1% to roughly 49,001, led lower by technology-linked names. ^[4]
South Korea: The Kospi dropped about 1.5% to around 3,994, pressured by electronics and auto shares. ^[5]
Hong Kong and mainland China: Markets were mixed, with Hong Kong recovering late to finish slightly higher while Shanghai edged up modestly. ^[6]

On a broader regional basis, MSCI’s Asia-Pacific index outside Japan was down around 0.3% earlier in the session, reflecting the tech-heavy tone. ^[7]

What Asia is watching next:
Investors in the region are also looking ahead to Japan’s central bank decision on Friday, with rate expectations in play as policymakers balance inflation dynamics and currency pressure. ^[8]

Europe stocks today: Muted trade as ECB and BoE decisions loom

In Europe, markets are largely in “wait-and-see” mode.

Around mid-morning trading in Europe, the STOXX Europe 600 hovered near flat-to-slightly higher territory (about +0.2%), with Germany’s DAX marginally higher as well. ^[9]

Why Europe is cautious:

Investors are holding back ahead of the ECB policy decision, where rates are widely expected to be unchanged but guidance is critical. ^[10]
The Bank of England decision is a major focus for UK assets after a surprise inflation downside helped lock in expectations for a cut. ^[11]
Traders are also watching the U.S. inflation report due later today, which could move global rates and risk appetite. ^[12]

Sector snapshot:
European moves were driven more by sectors than by broad index momentum. Retail shares were firmer (including gains in major consumer and apparel names), while healthcare and banks were a drag. Energy stocks found support as oil prices rebounded. ^[13]

U.S. stock market today: Futures edge higher after a tech rout

At 5:00 AM EST, U.S. index futures are modestly higher, suggesting an attempt to stabilize after Wednesday’s tech-heavy slide:

Nasdaq futures: about +0.3%
S&P 500 futures: about +0.1% ^[14]

That modest bid is being helped by a clear bright spot in semiconductors: Micron.

Micron headlines: Strong AI-memory demand boosts the premarket

Micron shares rose about 9% in U.S. premarket trading after the company delivered an upbeat profit forecast, pointing to strong pricing and tight supply conditions in high-bandwidth memory (HBM)—a critical component in training and running generative AI models. ^[15]

The message investors are pulling from Micron’s report is straightforward: even as markets question the cost of AI infrastructure, demand for the best-performing AI chips and memory remains intense—so intense that Micron’s leadership signaled tightness could extend beyond 2026. ^[16]

What happened on Wall Street last session: AI funding jitters hit Oracle, Nvidia, Broadcom

Wednesday’s U.S. session set the tone for today’s global open.

All three major indexes fell, with tech leading the decline:

Dow: down about 0.47%
S&P 500: down about 1.16%
Nasdaq Composite: down about 1.81% ^[17]

The selloff centered on concerns that parts of the AI boom are becoming too debt-dependent and too capital-intensive. Semiconductor bellwethers fell sharply (including Nvidia and Broadcom), and Oracle slid after renewed questions around AI data center financing. ^[18]

Central banks in focus: BoE expected to cut; ECB expected to hold

Bank of England: Rate cut expected after inflation cools

Markets widely expect the Bank of England to cut rates by 25 basis points to 3.75% from 4%, after UK inflation fell to 3.2% in November—a bigger drop than many forecasts anticipated. ^[19]

Sterling was relatively steady early Thursday after weakening on the inflation data, reflecting how heavily the rate-cut narrative has already been priced in. ^[20]

European Central Bank: Watch the guidance, not just the decision

The ECB is widely expected to keep rates unchanged, with attention turning to how policymakers describe the inflation outlook and whether they hint at tighter policy further out. ^[21]

U.S. CPI inflation report today: What makes this release unusual

The key macro catalyst for U.S. markets later this morning is the Consumer Price Index for November 2025, scheduled for 8:30 AM ET. ^[22]

This CPI release is unusual because the October CPI report was canceled following a government shutdown, meaning:

the November CPI publication will not include 1-month (month-over-month) percent changes where October data are missing, and
the focus will fall heavily on year-over-year inflation rates. ^[23]

Consensus expectations (year-over-year):

Headline CPI is forecast around 3.1%
Core CPI (excluding food and energy) is expected around 3.0% ^[24]

With futures only modestly higher, a meaningful surprise in the inflation print—either direction—could quickly reshape the day’s risk tone across equities, bonds, and the dollar.

Bonds, FX, and commodities: Cross-asset markets reflect the same tensions

Treasury yields: Slightly lower

U.S. Treasuries were modestly firmer early Thursday, with the 2-year yield around 3.47% and the 10-year near 4.14%, as traders positioned for the inflation report and central bank signals. ^[25]

Currencies: Sterling and euro in focus

Pound sterling: around $1.337 in early trading, after sliding on the inflation surprise that strengthened BoE cut expectations. ^[26]
Euro: around $1.174, with the ECB decision ahead. ^[27]

Oil and precious metals: Geopolitics lifts energy; silver near records

Oil prices extended a rebound from multi-year lows after President Donald Trump ordered a blockade of sanctioned oil tankers tied to Venezuela and amid reports of potential new U.S. sanctions on Russian oil if there is no Ukraine peace deal. ^[28]

Early Thursday levels cited in market coverage:

WTI crude: about $56.44 per barrel (up roughly 0.9%)
Brent crude: about $60.16 per barrel (up roughly 0.8%) ^[29]

Gold held near elevated levels while silver traded close to record highs, underscoring how quickly the market is shifting between risk-off hedging and tech-driven volatility. ^[30]

What to watch next today: The calendar that can move markets

Here are the catalysts most likely to shape “global stock market today” headlines from here:

U.S. CPI (8:30 AM ET): A pivotal read on inflation—delivered in an unusual format that emphasizes year-over-year trends. ^[31]
Bank of England decision: Markets are positioned for a cut; guidance and vote-split details matter. ^[32]
ECB decision: The hold may be expected—forward guidance is the potential market mover. ^[33]
Japan rate outlook into Friday: Traders remain alert for a policy hike and signals on the path for 2026. ^[34]
AI trade sentiment: After Wednesday’s drop, investors will watch whether semis broaden their rebound beyond Micron—or whether the “capex and debt” narrative deepens. ^[35]

Bottom line at 5:00 AM EST

Global markets today are balancing two competing stories: AI investment skepticism that has already hit high-profile tech names, and clear pockets of strength in AI-linked supply chains—especially memory and semiconductors—highlighted by Micron’s strong guidance.

With central banks and U.S. inflation data on deck, the next few hours are likely to determine whether Thursday becomes a stabilization day for risk assets—or the start of a broader repricing into year-end. ^[36]

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