​Stock Market Today: Nasdaq Hits Record High as AI Rally Builds Ahead of U.S.-China Summit

U.S. stocks were mixed on Tuesday as another round of enthusiasm surrounding AI pushed the Nasdaq Composite to a new intraday record. The tech-heavy index gained roughly 0.3%, while the S&P 500 hovered around the flatline and the Dow Jones Industrial Average fell about 0.3%, giving back some of Monday’s gains.

Technology remained the clear bright spot as investors continued to pile into AI-related names following Meta’s blockbuster Monday rally. Oil prices also eased, providing some relief on inflation, while markets turned their attention toward Thursday’s U.S.-China summit and the possibility of further progress on trade and AI cooperation.

Market Movers:

• Viking Therapeutics (VKTX) +23%: Shares surged after its experimental obesity drug VK2735 delivered up to 22% placebo-adjusted weight loss in a clinical trial while showing encouraging results with less frequent dosing. Patients maintained as much as 97% of their average induction weight loss when switched to every-other-week dosing, strengthening the drug’s potential position in the increasingly competitive obesity market.
• Vicor (VICR) +8%: Shares climbed after the power-module specialist sharply increased its third-quarter revenue outlook, now expecting sequential growth above 20% compared with its previous target of nearly 10%. The improved forecast reflects royalty revenue from a new licensing agreement covering Vicor’s Vertical Power Delivery technology, adding momentum to its AI power-infrastructure business.
• Shopify (SHOP) +7%: Shares jumped after Shopify partnered with Meta to allow users of its Muse AI agent to complete purchases from Shopify merchants using Shop Pay. The integration expands Shopify’s role in AI-driven commerce at a time when retailers and technology companies are increasingly competing over how autonomous shopping agents interact with online stores.
• SoFi Technologies (SOFI) +4%: Shares rose after SoFi and Mastercard announced that stablecoin settlement is now live across the bank’s debit and credit card program. SoFi is migrating its $25 billion card program to settlement using SoFiUSD, allowing transactions to use stablecoins behind the scenes without requiring merchants to hold the digital assets themselves.
• GameStop (GME) +4%: Shares gained after CEO Ryan Cohen disclosed the purchase of roughly 1.15 million shares at an average price of $22.94, an investment worth about $26 million. The purchase increased Cohen’s direct holdings to approximately 40.5 million shares and added to momentum after a strong month for the stock.
• Endava (DAVA) -23%: Shares plunged after CFO Mark Thurston was placed on administrative leave as the company launched an independent accounting investigation. Endava brought in AlixPartners and outside legal counsel to examine the accounting treatment of certain customer and supplier contracts while naming Conor McShane interim financial chief.
• Quest Diagnostics (DGX) -5% and Labcorp (LH) -3%: Shares fell after federal health officials announced preliminary plans to reduce Medicare reimbursement rates for diagnostic laboratory tests by as much as 15% beginning in 2027. The proposed changes could save Medicare roughly $1 billion annually but would put new pressure on reimbursement revenue for major laboratory operators.
• UBS Group (UBS) -3%: Shares declined as investors weighed proposed Swiss capital requirements that could force UBS to hold substantially more capital against its foreign operations. CEO Sergio Ermotti has warned that tougher requirements could increase funding costs and weigh on lending, dividends and share repurchases.

AI Momentum Keeps the Nasdaq Running

AI remained one of Wall Street’s strongest themes after Meta’s Muse assistant surged to the top of Apple’s App Store. Meta shares continued higher Tuesday after jumping more than 11% Monday, while optimism surrounding AI demand also supported semiconductor and infrastructure stocks.

The strength has helped the Nasdaq push to another record even as the broader market pauses. Shopify’s Meta partnership and Vicor’s stronger licensing outlook added to signs that AI investment is spreading beyond chipmakers into commerce, software and power infrastructure.

Oil Retreat Offers Inflation Relief

Oil prices remained under pressure Tuesday as markets monitored signs of improving Middle East supply, although crude pared deeper losses during the session. Brent hovered around $100 per barrel after briefly falling below that threshold, while U.S. crude traded near $95.

The retreat is important for Wall Street after elevated energy costs revived inflation concerns and contributed to expectations for tighter monetary policy. Any sustained improvement in oil supply could reduce some of that pressure, though continuing uncertainty surrounding the Strait of Hormuz means volatility remains high.

U.S.-China Trade Talks Move Into Focus

Investors are now looking toward Thursday’s meeting between U.S. President Donald Trump and Chinese President Xi Jinping after officials from both countries completed preparatory talks over the weekend. The discussions covered trade and potential cooperation on AI safety, while an extension of the existing trade truce is expected to be a central focus of the summit.

The stakes are particularly high for technology companies exposed to China. Any indication that the two countries can maintain their trade truce or deepen cooperation could ease some uncertainty hanging over semiconductor and AI stocks, although major differences between Washington and Beijing remain unresolved.

Looking Ahead

Tuesday’s market is increasingly split between powerful AI momentum and lingering macro uncertainty. The Nasdaq’s record run shows investors remain eager to capture growth tied to AI, while easing oil prices are removing some of the inflation pressure that recently weighed on equities. The U.S.-China summit now represents the week’s biggest scheduled catalyst. Investors will be watching for concrete developments on trade and technology, while oil prices and interest-rate expectations remain important variables for whether Wall Street can extend its September rally.