US stock market today: S&P 500 and Nasdaq hit record highs, Dow slips, Tesla jumps, Alphabet tops $3 trillion, Nvidia falls ahead of Fed rate cut

U.S. equities started the week with fresh momentum as investors balanced optimism around trade talks, corporate moves, and a highly anticipated Federal Reserve policy decision. The S&P 500 climbed 0.4% to another record high, the Nasdaq Composite gained 0.8%, and the Dow Jones Industrial Average slipped 14 points, holding near the flatline.

Tesla was the clear market mover on Monday after CEO Elon Musk disclosed a $1 billion insider stock purchase, his largest open-market buy ever and first since 2020. Shares surged 7.2%, reflecting investor confidence in Musk’s commitment at a time when the company is expanding into robotics and facing stiff EV competition.

While Tesla rallied, chip stocks faced a setback. Nvidia dropped 2.5% after China’s market regulator said the company had violated anti-monopoly rules linked to its 2020 Mellanox acquisition. The probe added to existing U.S.–China tech tensions, highlighting regulatory risks for semiconductor leaders.


ALSO READ: Alphabet hits $3 trillion market cap for the first time, joins the exclusive club with Apple, Microsoft and Nvidia as Google stock jumps 3.45% — key reasons behind the rally

Other U.S. chipmakers were caught in the crossfire. On Semiconductor fell 1%, while Analog Devices and Texas Instruments each lost nearly 3% as China launched an anti-dumping investigation into American analog chips.

This positive movement was supported by ongoing US-China trade talks and expectations of an interest rate cut by the Fed, which traders have largely priced in (96% probability for a quarter-point cut).

Today's movement:

• Dow Jones: +0.2%
• S&P 500: +0.4%
• Nasdaq Composite: +0.6% (reaching a record close)

The market momentum follows a strong previous week with the Nasdaq seeing two consecutive weeks of gains, and the S&P 500 having its best weekly performance since early August.

How are US-China trade talks influencing markets?

President Donald Trump said U.S.–China trade negotiations were “going well,” lifting investor sentiment after weeks of uncertainty. On Truth Social, Trump suggested progress on a deal involving a “certain” company—widely believed to be TikTok.

Washington has maintained its position: unless China compromises on tariff relief and tech restrictions, the U.S. is prepared to move ahead with a TikTok ban. Reuters reported that U.S. officials are pushing for a divestment deadline, keeping the app’s future in limbo.

Markets responded positively, with a Bloomberg index of trade uncertainty falling to its lowest level this year, suggesting easing geopolitical risks.

What to expect from the Fed meeting this week?

The biggest market catalyst remains the Federal Reserve’s policy decision on Wednesday. Data pointing to slower job growth and cooling inflation has fueled expectations of rate cuts.

• CME FedWatch Tool shows a 96% probability of a 0.25% rate cut.
  
  
• A larger 0.50% cut holds just a 3.6% chance.
  
  

Lower rates could further support equities, particularly AI-linked technology stocks and housing-sensitive sectors. Still, strategists warn of a potential “buy the rumor, sell the fact” reaction, as investors shift focus to whether rate cuts can offset slowing economic momentum.

Alphabet joins the $3 trillion club

Another milestone came from Alphabet (Google’s parent), which crossed the $3 trillion market cap mark on Monday. Shares jumped 3.4%, bringing year-to-date gains to 31.5%.

Alphabet now stands alongside Apple, Microsoft, and Nvidia in the exclusive $3T valuation club. The rally followed relief around an antitrust ruling that stopped short of forcing Google to divest its Chrome browser.

Economic data keeps pressure on outlook

The Empire State Manufacturing Index fell sharply to -8.7 in September, marking the first contraction since June. New orders and shipments dropped significantly, signaling ongoing weakness in factory activity.

The reading came in far below the Dow Jones estimate of 4.5, reinforcing concerns that growth momentum is fading even as equity markets continue to test new highs.

In today's US stock market rally on September 15, 2025, the top stock gainers and losers were as follows:

Top Gainers:

• GlucoTrack (GCTK): +117%
• Office Properties Income Trust (OPI): +80%
• HCW Biologics (HCWB): +68%
• Vestand (VSTD): +65%
• IonQ (IONQ): +18.2%
• Warner Bros. Discovery (WBD): +16.7%
• Tesla (TSLA): +7.4%

Top Losers:

• Arista Networks (ANET): -8.9%
• Moderna (MRNA): -7.4%
• Oracle (ORCL): -5.1%
• Charles River Labs (CRL): -4.3%
• Pfizer (PFE): -4%
• Royal Caribbean (RCL): -3.9%
• Nvidia (NVDA): -2.5% due to regulatory concerns on its AI chip dominance

Most active stocks in today's trading

The most active stocks in today's US trading by volume and value include:

• Reddit Inc. (RDDT) with trading value of around $320 million and price of $257.37
• Lululemon Athletica Inc. (LULU) with $319.89 million traded at $160.93
• Palo Alto Networks, Inc. (PANW) with $319.67 million traded at $200.55
• Rigetti Computing, Inc. (RGTI) with $316.8 million traded at $19.00
• Exxon Mobil Corporation (XOM) with $285.76 million traded at $112.25
• Live Nation Entertainment, Inc. (LYV) with $282.86 million traded at $173.65
• Qualcomm Incorporated (QCOM) with $278.45 million traded at $161.88
• Bloom Energy Corporation (BE) with $249.96 million traded at $64.47
• NuScale Power Corporation (SMR) with $249.28 million traded at $36.67
• Intuit Inc. (INTU) with $249.26 million traded at $645.49

These stocks saw significant trading volumes and strong investor interest today across sectors including technology services, consumer goods, energy, and health technology.