US Market Breakdown: AI Revenue Scare Hits Chips, Week of 5 October 2026

The S&P 500 set a record close on Tuesday, and by Thursday afternoon the artificial-intelligence trade that carried it there was being picked apart. A Financial Times report that OpenAI's annualised revenue was running at roughly $50bn at the end of September — rather than the $68bn to $70bn figure circulating among investors — hit the listed companies that sell it hardware and capacity. Oracle fell about 5.5%, Nvidia around 3% and AMD between 3% and 4.5%, and the Nasdaq Composite shed 1.25% to 27,193.34.

It was not enough to spoil the week. All three headline indices finished higher, but the leadership changed hands: defensive sectors carried the gains while technology lagged. And Friday's most violent single move had nothing to do with chips: SpaceX's agreement to buy nationwide 800 MHz spectrum sent America's cell-tower landlords soaring and, by Axios's reckoning, knocked some $36bn off the combined market value of the country's three big mobile carriers in one session.

Underneath all of it sat the bond market. The 10-year Treasury yield touched its highest level since April 2002, and the minutes of the Federal Reserve's September meeting told investors in plain terms to expect another rate rise before the year is out.

Wall Street

The week began quietly and then produced a record. The S&P 500 closed Monday 5 October at 7,773.95, before adding more on Tuesday to finish at 7,818.93 — an all-time closing high, with an intraday peak of 7,844.52, and the first close above 7,800. The Nasdaq Composite set its own closing record the same day at 27,599.89.

Wednesday broke the spell. With the 10-year Treasury yield pushing towards 5.37%, the S&P 500 slipped 0.22% to 7,801.77, the Nasdaq eased 0.22% to 27,538.69 and the Dow fell about 0.66% to 51,179.87, dragged down by a near-6% fall in Caterpillar. Thursday was worse for technology but not for the wider market: the S&P 500 lost 0.47% to 7,765.36 and the Nasdaq 1.25%, while the Dow crept up 51.77 points to 51,231.64 as money left the AI complex for more prosaic businesses.

Friday 9 October reversed the mood. With oil prices and Treasury yields stabilising, the Dow rose 0.83% to 51,654.95, the S&P 500 gained 0.59% to 7,811.54 and the Nasdaq added 0.64% to 27,366.17. That left the S&P 500 up 1.2% on the week, the Dow up 0.9% — its best week since the week ended 7 August — and the Nasdaq up 0.6%, a fourth straight weekly gain. Through Wednesday the S&P 500 was ahead roughly 14% in 2026, the Nasdaq about 18.5%.

Monday 12 October, the most recent completed session, continued the same rotation. The Dow rose 0.38%, or 195.60 points, to 51,850.55 — a third straight advance — while the S&P 500 edged down 0.06% to 7,807.24 and the Nasdaq fell 0.44% to 27,245.90. The Russell 2000 slipped 0.45%. The drag was memory chips, and Micron in particular.

The week's biggest movers

PTC was the week's cleanest gain. Schneider Electric agreed to buy the industrial software group for $205 a share in cash, valuing its equity at about $22.6bn — roughly £17bn at the week's rate of about $1.32 to the pound — a 42.3% premium to the previous close. PTC closed at $192.26, up 33.5%. Schneider's own Paris-listed stock fell sharply on the news.

The spectrum story was the week's most consequential. SpaceX agreed to buy nationwide 800 MHz spectrum from Grain Management, a deal the Wall Street Journal valued at roughly $8bn in cash (around £6bn) and which still needs clearance from the Federal Communications Commission. Investors read it as a sign SpaceX might one day need ground sites: Crown Castle jumped more than 13% and American Tower more than 8%. The carriers went the other way, with CNBC's midday round-up showing T-Mobile down 13% and AT&T and Verizon down about 10% each, though other outlets recorded smaller declines at different points in the session. Bernstein made the point that buying spectrum is an option rather than a signed lease, and BofA noted that a terrestrial build would take years of permitting and investment.

Humana closed at $431.87 on Friday, up 11.6%, after the 2027 Medicare Advantage star ratings were published. The insurer said 95% of its members would be in plans rated four stars or better next year, against 20% this year; J.P. Morgan had expected 60% to 70%. The same release went against its rivals, with J.P. Morgan estimating UnitedHealth's share of four-star-plus plans falling to about 67% from 81% and CVS Health's to roughly 70% from 84%. Elsewhere in healthcare, Teva rose about 6% on Friday after the Food and Drug Administration approved Weltruza, its monthly injectable for schizophrenia in adults.

Company news in focus

Deal-making was busy. Alongside Schneider–PTC, C.H. Robinson agreed on 5 October to buy fellow freight broker RXO in a cash-and-stock transaction valued at about $5.8bn: RXO holders receive $17.25 in cash plus 0.0856 C.H. Robinson shares, an implied $30.25 a share, leaving them with roughly 11% of the combined group. RXO rose nearly 22.5% on the announcement while the acquirer fell almost 11%. A day later, McKesson and private equity firm Clayton, Dubilier & Rice agreed to buy home-infusion provider Option Care Health in a deal valued at around $5.8bn.

The week's most awkward boardroom news landed on Monday, when Bausch + Lomb said chief executive Brent Saunders was leaving by mutual agreement with the board, chairman Thomas Appio stepping in on an interim basis while remaining chief executive of Bausch Health. No reason was given. Endpoints News reported the shares down about 3%, and analysts at Evercore and Leerink called the timing a surprise. The company signalled it expects to raise full-year adjusted EBITDA guidance when it reports on 28 October.

On the regulatory side, Webull fell 20% on Wednesday after CNBC reported a congressional panel had concluded the broker's ties to the Chinese government create a national security risk. SpaceX had a second, less welcome story: shares slipped 2.5% on Wednesday after Bloomberg reported preliminary talks to raise about $40bn of debt — roughly $10bn of loans and $30bn of bonds, per the Financial Times — to fund Nvidia chips for its data centres. Its five-year credit default swap spreads reportedly hit a record 194 basis points.

Among analyst moves, Cantor Fitzgerald trimmed its Amazon price target on Monday while keeping an overweight rating, and the shares fell 1.1% to about $259.53. Apple went the other way, rising 1.3% after JPMorgan lifted its target and Bank of America reiterated a buy rating.

Earnings in focus

Third-quarter season had not properly begun, but the early reporters told variations of one story: revenue holding up, costs biting. US companies report quarterly rather than half-yearly, and almost always before the opening bell or straight after the close, which is why much of the reaction below happened outside normal hours.

Constellation Brands reported on 6 October: net sales up 6% to $2.63bn and adjusted earnings of $3.74 a share against expectations near $3.55. It reaffirmed comparable full-year guidance of $11.20 to $11.90 a share and declared a quarterly dividend of $1.03, payable 13 November. Shares still slipped after hours, by about 4.5% on one account.

Levi Strauss followed on 7 October with a narrow beat, lifting full-year adjusted earnings guidance to $1.54–$1.56 a share largely on tariff refunds while cutting its net revenue growth outlook to 7%, the bottom of its prior range. US revenue fell 1% and the shares dropped nearly 4% on Thursday.

PepsiCo's numbers on 8 October beat on both lines — adjusted earnings of $2.34 a share against a $2.29 consensus, revenue of $25.27bn — but the guidance went the wrong way. The company cut its 2026 core earnings growth forecast to 2.5%–3.5%, having previously pointed to the low end of a 5%–7% range, citing weaker margins, higher input costs, the expiry of a third-quarter tariff benefit and commodity hedges rolling off. Management conceded North American carbonated soft drinks are underperforming. Reports of the share reaction conflicted: CNBC had the stock up about 2% in morning trading, others a small fall before the open.

Delta Air Lines opened the airline reporting season on 9 October and missed, with adjusted earnings of $1.72 a share. Adjusted revenue rose 16% to about $17.6bn and premium-cabin revenue 18%, but quarterly fuel expense jumped 62% to $4.1bn. Delta cut full-year adjusted earnings guidance to $5.10–$5.60 a share from $6.50–$7.50 and said the annual fuel bill would rise by roughly $6bn. The finance chief said the entire downgrade came from fuel; the chief executive said he saw no cracks in travel demand. Shares fell about 3% in early trading.

Sectors in focus

The week was a rotation, not a rally. Defensive and commodity-linked sectors led — trackers put utilities, consumer staples and energy all up roughly 3% or more over the five sessions, though they disagree on the order — while technology lagged, one tally putting it down about 1% on the week.

That ordering explains the index arithmetic: the Dow, with little megacap AI weighting, beat the Nasdaq over the week. Megacap concentration cuts both ways, and here it cut against the composite — the OpenAI revenue report concerned a handful of index heavyweights rather than corporate America, yet took 1.25% off the Nasdaq in a session.

Industrials had their own problem, and it was rates rather than AI. Caterpillar's fall on Wednesday to $813.83 came as 30-year Treasury yields hit an intraday 5.73%, their highest since May 2002 — a direct hit to a business that sells expensive machinery on credit.

Macro and the Fed

The bond market was the week's real engine. The 10-year Treasury yield jumped roughly seven basis points on Monday 5 October to 5.349%, its highest since 3 April 2002, and pressed towards 5.37% by Wednesday morning. The 30-year reached about 5.70% on Wednesday. By Friday both had eased, to around 5.24% and 5.60% respectively. The consequence for American households showed up immediately: Forbes reported the average 30-year fixed mortgage rate rising from 7.30% to 7.49%. Reporting attributed the move to elevated energy prices, a projected $1.9 trillion federal deficit, heavy AI-related corporate borrowing and parallel bond sell-offs in Japan, Britain and France.

Wednesday 7 October brought the minutes of the Fed's 15–16 September meeting, at which the committee voted unanimously to raise the federal funds rate by a quarter point to 3.75%–4.00%. "Most participants assessed that another increase in the target range for the federal funds rate would likely be appropriate by year end," the minutes said, without saying when. Bank shares fell on the day. Pricing had already shifted the expected hike from October to December after September's soft payrolls report — 29,000 jobs against an 84,000 forecast, unemployment at 4.2%, published 2 October, just before this window — with December odds put near 81%.

In commodities, Brent crude traded around $105 a barrel on Friday and WTI near $92, keeping the fuel-cost pressure on Delta Air Lines and its peers firmly in place. Gold was at $4,169.50 an ounce late on Monday, per Kitco, still some 22% below its January 2026 peak.

Still to come

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