Investing.com -- U.S. stock futures fell sharply Monday, as investors assessed a decision by Moody’s to downgrade its rating of the country’s credit.

Here are some of the biggest premarket U.S. stock movers today:

• Nvidia (NASDAQ: NVDA ) stock fell 3.1% after the chipmaker’s CEO Jensen Huang unveiled a host of new artificial intelligence technology -- both for enterprise and consumer applications -- when delivering the keynote address at the Computex AI exhibition in Taiwan.

• Walmart (NYSE: WMT ) stock fell 1.8% after U.S. President Donald Trump over the weekend said that the retail giant should absorb price increases stemming from higher import tariffs, and warned against any price increases.

• Microsoft (NASDAQ: MSFT ) stock fell 0.8%, with the software giant hosting its annual software developer conference in Seattle, drawing thousands of coders looking to turn the past years of investments into artificial intelligence into profitable products and services for consumers and businesses.

• JPMorgan Chase (NYSE: JPM ) stock fell 0.8%, with the major lender set to hold its much-anticipated investor day later in the session, where CEO Jamie Dimon is tipped to provide updates on his view of the implications of the levies.

• Netflix (NASDAQ: NFLX ) stock fell 1.7% after JPMorgan downgraded its stance on the streaming giant to ‘neutral’ from ‘overweight’, citing reduced risk-reward appeal following a sharp rally in the stock recently.

• BP (NYSE: BP ) ADRs fell 0.8% after Jefferies downgraded its stance on the oil major to ‘hold from ‘buy’, citing increased execution risk amid lower oil price forecasts for 2025 and 2026, in a note dated Monday.

• Qualcomm (NASDAQ: QCOM ) stock fell 0.8% after the semiconductor company announced it will develop custom data center CPUs designed to link with Nvidia’s AI chips, marking a renewed push into the server processor market.

• Blackstone (NYSE: BX ) stock fell 1.9% after the investment management company said its infrastructure unit will buy the utility firm TXNM Energy in a $11.5 billion deal.