US Close 28 September 2026: S&P 500 -0.77% to 7,684 as the 10-Year Yield Reaches 5.24% and an OpenAI Pause Weighs on Chips
The S&P 500 closed at 7,683.69 on 28 September 2026, down 59.72 points or 0.77%, after the 10-year Treasury yield rose 5.6 bp to 5.24%, its highest close since 2007, and OpenAI paused training of its most advanced models. MDB.US fell 18.46% to $334.68 after chief executive CJ Desai left MongoDB to join Meta. WTI crude rose 0.95% to US$93.29 after President Trump rejected Iran's plan to reopen the Strait of Hormuz, which lifted bets on another Fed rate hike and pushed gold 4.00% lower.
At a glance
| Index | Close | Change |
|---|---|---|
| S&P 500 | 7,683.69 | -0.77% |
| Nasdaq Composite | 26,820.38 | -0.92% |
| Dow Jones Industrial Average | 51,481.51 | -0.67% |
| Russell 2000 | 2,817.91 | -0.69% |
| VIX | 16.07 | +8.07% |
US 10-year yield 5.24%, up 5.6 bp. US 30-year yield 5.561%, up 5.7 bp, its highest since 2004. US Dollar Index 101.20, up 0.22%. Gold US$4,148.50 an ounce, down 4.00%, its lowest since 5 August.
171 of the 250 largest US-listed names by market value closed lower and 79 higher.
What moved the index
The S&P 500 lost 77 bps on 28 September 2026, and the four named drivers below account for about 61 bps of it.
| Driver | Move | Index contribution |
|---|---|---|
| Largest tech and AI names (META.US, MSFT.US, AMZN.US, TSLA.US, AAPL.US, AMD.US, MU.US, ORCL.US) net of NVDA.US | -0.78% to -4.79%; NVDA.US +1.68% | about -38 bps |
| Financials (XLF.US) | -1.19% | about -15 bps |
| Industrials (XLI.US) | -0.97% | about -8 bps |
| Utilities, real estate and materials, net of health care, staples and energy | -0.51% to -0.66% against +0.10% to +0.33% | about 0 bps |
META.US gave up 4.79% to $715.62, about 14 bps on its own, after OpenAI halted training and testing of some of its most advanced models, the second such pause in three months. NVDA.US rose 1.68% to $228.86 against the chip group after Nvidia added $150 billion to its buyback, taking the total authorization to $235 billion, worth about 13 bps back. JPM.US -1.89%, BAC.US -2.17% and GS.US -2.05% fell as the 10-year yield reached 5.24%. The residual 16 bps came from breadth: 171 of the 250 largest names closed lower.
Session highlights
5.67% was the INTC.US loss to $116.03 on 28 September 2026, the largest among the big chipmakers after the OpenAI pause.
- ARM.US -8.70% to $283.33 and QCOM.US -7.17% to $187.48 led the chip designers lower; AMD.US lost 3.61%, MRVL.US 3.83% and MU.US 2.61%.
- GFI.US -12.88% to $35.18 as gold fell 4.00% to US$4,148.50; AEM.US lost 5.31% and NEM.US 4.43%.
- TSLA.US -3.94% to $357.45, the second-largest index drag among the top ten names behind META.US.
- 30-year Treasury yield at 5.561%, up 5.7 bp, with the 10-year at 5.24%, as oil rose on the Hormuz standoff.
- XOM.US +1.20% to $162.52 as WTI climbed to US$93.29.
Sector scorecard
Three of the eleven S&P 500 sectors rose on 28 September 2026, led by health care at +0.33%.
- XLV.US +0.33%, XLP.US +0.27% and XLE.US +0.10% were the only gainers.
- XLC.US -1.58% and XLY.US -1.41% were the weakest, with META.US the main communication-services drag and TSLA.US and AMZN.US the discretionary drags.
- XLF.US -1.19% and XLI.US -0.97% followed; XLK.US lost 0.89%. Dispersion from best to worst sector was 1.91 points.
- Technology held the widest internal spread: NVDA.US +1.68% and PANW.US +4.63% against ARM.US -8.70% and QCOM.US -7.17%.
Top movers
| Gainer | Change | Close |
|---|---|---|
| KOD.US | +177.96% | $89.92 |
| AMC.US | +11.90% | $3.29 |
| ABCL.US | +9.61% | $13.92 |
| CAAP.US | +9.09% | $26.05 |
| HHH.US | +8.07% | $73.95 |
| Loser | Change | Close |
|---|---|---|
| OCUL.US | -20.67% | $7.66 |
| MDB.US | -18.46% | $334.68 |
| GFI.US | -12.88% | $35.18 |
| AUR.US | -12.42% | $5.29 |
| MOD.US | -11.63% | $175.04 |
- KOD.US +177.96% to $89.92 after its Phase 3 DAYBREAK study in wet age-related macular degeneration met its primary endpoint (p = 0.0007); Kodiak plans a biologics license application in the fourth quarter of 2026.
- AMC.US +11.90% to $3.29, its highest price of 2026, extending gains after last week's $3.9 billion debt refinancing and the launch of its Leawood Films distribution arm.
- ABCL.US +9.61% had no same-day announcement; its ABCL635 Phase 2 hot-flash data is due at the IMS World Congress on Menopause.
- CAAP.US +9.09% on about three times its average daily volume. Unannounced, likely flow-driven.
- HHH.US +8.07%, a third straight gain after insider buying that included 25,000 shares bought by the executive chairman on 23 September at $64.12.
- OCUL.US -20.67% to $7.66. Unannounced, likely flow-driven.
- MDB.US -18.46% after CJ Desai left to become Meta's chief enterprise platform officer; former chief executive Dev Ittycheria returns on an interim basis, and MongoDB reaffirmed third-quarter adjusted EPS guidance of $1.57 to $1.61.
- AUR.US -12.42% to $5.29, extending losses since its September investor day, when its 2030 targets of 30,000 driverless trucks and $5 billion in revenue missed expectations.
- MOD.US -11.63% had no company announcement; it fell alongside AI infrastructure names BE.US -8.95% and CRDO.US -8.67%.
After-hours earnings
Sources confirmed no after-the-bell earnings reaction from a large US company by the time of writing on 28 September 2026.
- MU.US, at $1,053.98 after a 2.61% loss, reports on Wednesday 30 September, the first large chip report since the OpenAI pause.
- NKE.US reports on Thursday 1 October; Carnival, Accenture, CarMax, Conagra and McCormick also report this week.
Next session catalysts (ET)
- Tue 29 Sep, 10:00am: JOLTS job openings and the Conference Board consumer confidence index.
- Wed 30 Sep, 8:30am: Q2 GDP third estimate, corporate profits, and personal income and outlays, which carries the PCE price index.
- Thu 1 Oct: ISM manufacturing PMI and weekly jobless claims.
- Fri 2 Oct, 8:30am: September employment report.
- 5.24% on the 10-year and 5.561% on the 30-year are the yields going into Tuesday's session, with WTI at US$93.29.
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