The fluctuating fortunes of AI stocks took a downturn on Tuesday, pulling Wall Street lower. The S&P 500 dropped by 0.4% despite most stocks in the index showing gains. Artificial-intelligence stocks exerted downward pressure, causing the Nasdaq composite to fall by 1.2%, while the Dow Jones Industrial Average decreased by 130 points, or 0.2%, from its record high.

The initial weakness began in Asia, where Samsung Electronics saw a 6.9% drop in Seoul. Although the tech giant’s preliminary performance for the second quarter looked robust, with an expected 1,800% surge in operating profit from last year, it fell short of investor expectations. Samsung Electronics’ stock had already more than doubled earlier in the year.

In recent weeks, AI stocks on Wall Street have experienced similar pressures. Concerns about high valuations and doubts regarding AI’s ability to drive sufficient productivity and profits have weighed heavily on investors. Notable declines included those from Advanced Micro Devices, down 6.5%, Intel, declining 9.7%, and Micron Technology, falling 4.7%.

SpaceX’s xAI business took a hit, dropping 6.8% during its first trading after inclusion in the Nasdaq 100 index. In other sectors, Vertex Pharmaceuticals slipped by 1.4% following its agreement to purchase Crinetics Pharmaceuticals for $85 per share in cash. Crinetics, which specializes in endocrine disease therapeutics, saw a surge of 98.7%. Rivian Automotive decreased by 18.1% after announcing the sale of 75 million shares, affecting earlier shareholders’ stakes.

The S&P 500 closed at 7,503.85, down by 33.58 points. The Dow Jones Industrial Average fell to 52,925.15, and the Nasdaq composite dropped to 25,818.69. The market also faced pressure due to rising oil prices. The British military reported that three tankers were hit by projectiles in the Strait of Hormuz. Subsequently, the U.S. revoked a license for Iranian oil sales, part of an interim deal to halt hostilities between the two nations. This setback diminished hopes for a full reopening of the Strait of Hormuz for oil tanker traffic from the Persian Gulf.

Oil prices rose, with Brent crude increasing by 3%, settling at $74.16 per barrel. Higher oil costs added inflationary pressures, causing Treasury yields to rise. The 10-year Treasury yield moved up to 4.54%, from 4.48% late Monday and 3.97% prior to the conflict with Iran. Investors have been uneasy with high yields globally since the war pushed oil prices above $100 per barrel in March. The concern is that elevated inflation may compel the Federal Reserve and other central banks to increase interest rates. While higher rates can restrain inflation, they often slow economic growth and negatively impact investment prices.

International stock markets saw downturns. South Korea’s Kospi fell by 4.9%, heavily affected by Samsung Electronics, which represents over a quarter of the index. Japan’s Nikkei 225 decreased by 2.1%, and Germany’s DAX dropped by 1.4%, marking significant global movements.

AP Business Writers Matt Ott and Elaine Kurtenbach contributed to this report.