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Closes30 Oct
S&P 5007,580−1.82%Nasdaq25,437−2.86%US 10Y4.98%−7 bp29 OctDollar102.04−0.15%29 OctBrent futures$117.64+2.4%WTI futures$102.00−0.76%29 OctGold futures$4,031−0.5%29 OctLiveBitcoin$77,381−0.59%Ether$2,243−0.27%SolanaOfficial closes, each dated, from the record the Scorecard grades on: exchange data via Yahoo Finance, US yields from FRED. Crypto live from CoinGecko.
Edition 005Wednesday 28 October 2026Before the US open, 09:00 GMT, with Tuesday’s closes

Chips lift the Nasdaq 1.2% before the Fed and Microsoft and Alphabet report.

Details of Anthropic’s planned listing carried chipmakers higher for a third session, and our first test, F-010, held. Brent fell 1.7% on Iran talks, then recovered in Asia. The Fed decides at 14:00 New York; Microsoft and Alphabet report after the close.

By the Causa DeskPublished

What moved markets on Tuesday 27 October 2026, and why?

The Nasdaq Composite closed up 1.18% at 26,477.81 on Tuesday, the S&P 500 rose 0.60% to 7,722.60 and the Dow was flat at 52,377.57. Reuters tied the gains to details of Anthropic’s planned listing, which lifted chipmakers for a third straight session, while Boeing fell 10.7% after cutting its delivery target.1

F-010, the test on Monday’s Anthropic file, held. It would have failed on a Nasdaq close below 25,955.34 by Tuesday, and the index finished 2.0% above that line. It is the first call on our Scorecard to reach its deadline intact.1

Brent futures settled at $113.88, down 1.67%, after Iran’s security council chief met Supreme Leader Mojtaba Khamenei following talks with Saudi Arabia, Turkey and Pakistan. Brent recovered about 1.3% in Asian trade on Wednesday.23

The Fed is expected to hold its target range at 3.75% to 4% at 14:00 New York, with markets pricing a hike in December instead. Microsoft and Alphabet report after the close, the first direct test of the spending that has carried chipmakers for three sessions.145

Today's Cause Map
Hover or tab to a move to trace its causes. Select it to open the file.Each move, traced back to what started it. Tap one to open its file.
Cause Map for 28 October 2026 Nasdaq +1.2%, traced to Chip demand looks committed, Anthropic listing details. Brent -1.7%, traced to War premium trimmed, Iran keeps talking. WHAT HAPPENEDFIRST EFFECTKNOCK-ONWHAT MOVED Anthropic listing detailsComputing commitments in the filingIran keeps talkingRezaei meets KhameneiChip demand lookscommittedWar premium trimmedNasdaq+1.2%Brent−1.7%
  1. Nasdaq+1.2%BPlausibleOpen the file
    1. What happenedAnthropic listing detailsComputing commitments in the filing
    2. First effectChip demand looks committed
  2. Brent−1.7%BPlausibleOpen the file
    1. What happenedIran keeps talkingRezaei meets Khamenei
    2. Knock-onWar premium trimmed
Solid lines are well-evidenced links. Dashed lines are our best reading where other explanations are still live.

The Board

Market moves and their Cause Files
AssetLevelMoveSize of moveWhy it moved
Nasdaq Composite26,478+1.18% BPlausibleAnthropic’s listing details carry chipmakers into the earnings test
S&P 5007,723+0.6% F-008 needs a close above 7,757.17 with Brent above $112, about 0.4% away.
Dow Jones52,378+0.03% Boeing down 10.7% on its delivery cut.
Brent crude$113.88−1.67% BPlausibleBrent falls on Iran talks, but oil still sets the Fed’s path
US crude$99.90−1.83% Brent falls on Iran talks, but oil still sets the Fed’s path
Gold$4,073+0.86% Up with the dollar before the Fed.
US 10-year yield5.00%+1 bp Market level at the close. The official FRED figure follows.

Closing levels on Tuesday 27 October 2026. Sources are numbered in each Cause File.

Nasdaq Composite +1.18% to 26,477.81

Anthropic’s listing details carry chipmakers into the earnings test

The Nasdaq rose 1.18% as details of Anthropic’s planned listing lifted chipmakers for a third session, and F-010 held. Microsoft and Alphabet report tonight, the first direct check on whether the spending behind the rally is paying back.

  1. What happened
    Anthropic’s listing details circulate
    The filing shows about $430bn of computing commitments.
  2. Then
    Chip demand looks committed
    Chipmakers up for a third straight session, per Reuters.
  3. Then
    Technology leads, energy lags
    Best and worst S&P 500 sectors on the day.
  4. What moved
    Nasdaq +1.18%
    26,477.81 at the close.
BPlausibleF-014, test closes 30 October 2026Open the full Cause File
Brent crude −1.67% to $113.88

Brent falls on Iran talks, but oil still sets the Fed’s path

Brent fell for a second session as Iran’s leadership reviewed talks with Saudi Arabia, Turkey and Pakistan. Attacks on shipping remain at record levels, and the Fed meets today with markets pricing a December hike that is hard to explain without oil.

  1. What happened
    Iran’s leadership reviews the talks
    Security council chief Rezaei meets Khamenei.
  2. Then
    Traders trim the war premium
    Brent was above $117 last week.
  3. Then
    Shipping risk stays high
    October attacks near Hormuz the most since 2017.
  4. What moved
    Brent −1.67%
    December contract, $113.88 at settlement.
BPlausibleF-015, test closes 13 November 2026Open the full Cause File

What we are watching

Wednesday 28 October, 14:00 New YorkFederal Reserve decision

A hold at 3.75% to 4% is expected. The statement and press conference will show how much weight the Fed gives oil against a softer labour market, which is the question behind F-015.14

Wednesday 28 October, after the closeMicrosoft and Alphabet results

Azure growth against Microsoft’s guide of about 45%, Google Cloud growth and any change to spending plans. F-014 is ruled on the market’s response.5

Wednesday 28 October, 10:30 New YorkUS crude inventories

The weekly government count, where a Reuters poll expects crude stocks to be little changed.3

Friday 30 OctoberDecember Brent expires; F-002 and F-014 deadlines

Our Brent calls move to January, with each line adjusted by the gap between the two contracts at expiry.6

Sources

Every source used in this edition. Each Cause File numbers its own.

  1. Wall Street ends higher on revived AI momentum Reuters, via Yahoo Finance, 27 October 2026
  2. Brent drops US$1.93 a barrel on October 27 amid Iran talks The Nation (Thailand), 28 October 2026
  3. Brent Crude Oil Price: $115.59 on Fed Decision Day After Houthi Ras Tanura Claim FinanceFeeds, 28 October 2026
  4. October 2026 Fed meeting preview: How to position your savings ahead of the next rate decision Raisin, 23 October 2026
  5. Microsoft, Alphabet and Amazon Lead the Earnings Week of October 26 StockTitan, 26 October 2026
  6. Brent Oil Futures Contracts Investing.com, 26 October 2026
  7. Closing Look, Tuesday, October 27, 2026 Capp Notes, 27 October 2026
  8. Anthropic IPO live updates: S-1 filing discloses $16.3B in first-half revenue, plans to list as ANT Yahoo Finance, 26 October 2026
  9. Stock Market Today (Oct. 27, 2026): Boeing falls 10% while Big Tech buoys S&P 500, Nasdaq TheStreet, 27 October 2026