Stock Market Midday, Sept. 28: Stocks Slide as Yields Rise, MongoDB Tumbles

At 11:56 AM ET on September 28, major U.S. stock market indices were all in decline, with the S&P 500 down 0.78%, the Nasdaq Composite falling 0.90%, and the Dow Jones Industrial Average trading at 0.72% lower. Factors contributing to the market's downturn included geopolitical tensions and increasing energy costs, which dampened investors' appetite for risk. Gold prices dropped by 3.83% to $4,122.91, while the 10-Year Treasury yield rose by 8 basis points to 5.26%.

Certain sectors performed better than others amid the overall market sell-off. Energy and consumer defensive stocks emerged as the biggest gainers, while consumer cyclicals and communication services experienced the most significant losses. Tech giant Nvidia Corporation benefited from a massive $150 billion share buyback announcement, causing its stock to rise.

However, MongoDB, Inc. suffered a dramatic drop following the unexpected departure of its CEO, Chirantan Bhatt Desai, who is now joining Meta Platforms. Chip manufacturers such as Intel and Advanced Micro Devices also saw declines due to concerns surrounding artificial intelligence safety.