U.S. stocks experienced a significant decline on Thursday, as the S&P 500 decreased by 0.9%, the Nasdaq fell by 1.5%, and the Dow Jones dropped nearly 400 points. This downturn was primarily influenced by losses in consumer discretionary and technology sectors. Renewed apprehensions over inflated valuations of AI-related stocks emerged amidst mixed earnings announcements. Simultaneously, concerns about a more pronounced slowdown in the labor market escalated following the Challenger report, which revealed that U.S. companies announced the largest number of job cuts for any October in 22 years, primarily due to AI adoption and cost-reduction strategies. Qualcomm's shares fell by 4.8% after its intellectual property licensing revenue narrowly missed expectations. Tesla saw a 5% decrease ahead of its annual shareholder meeting scheduled for later in the day. Other significant declines included Oracle (down 4.2%), Palantir Technologies (down 5%), and AMD (down 7.4%). Most major megacap stocks also saw decreases, including Nvidia (down 2.6%), Microsoft (down 1.8%), Amazon (down 2.7%), Meta (down 2.3%), and Alphabet (down 0.2%).