The S&P 500 fell 4.4% on 5 November, its worst day since the April 2025 tariff shock.^[1] The Nasdaq composite fell 5.5% and entered correction territory.^[2] It closed 11.9% below its record close of 6 October.^[3] S&P 500 companies lost about $3 trillion in market value in that one session.^[4] The day was the largest step in a slide that ran for a month. Set side by side, the reports from eight outlets show the losses fell on AI builders and their suppliers. Several of those companies fell on the day of their own results, including results that showed revenue growth. Other large technology stocks were at highs the day before. The index record The Nasdaq 100 set its peak on 6 October.^[5] It fell about 3.5% on Friday, 30 October.^[6] The iShares Semiconductor ETF lost about 8% that day.^[7] On Monday, 2 November, the Nasdaq 100 fell about 1.4% and closed more than 10% below its October peak.^[5] That was its third correction of 2026, after March and July.^[8] By the close on Wednesday, 4 November, it had recovered to about 9% below the peak.^[9] On 5 November the Nasdaq composite fell 5.52%.^[10] It closed at 24,315.^[11] The S&P 500 fell 4.36%.^[12] The Dow Jones Industrial Average lost 3.44%.^[13] In points, the Dow fell 1,833.^[14] The fall erased the relief rally of the day before.^[15] The Philadelphia Semiconductor Index fell about 7% in early trading.^[16] The companies Advanced Micro Devices fell 17.3%.^[17] Nvidia fell 9.3%.^[18] Nvidia lost almost $450 billion in market value that day.^[19] Nvidia and Qualcomm each fell more than 9%.^[20] AMD, Micron and Applied Materials each fell by double digits.^[21] Nebius fell more than 17% during the session.^[22] Micron and AMD each fell more than 15% during the session.^[23] GE Vernova fell 7.5%.^[24] The SOXX semiconductor ETF fell 12%.^[25] All five of AMD's peer chip makers fell more than 9%.^[26] Memory, AI cloud and chip stocks took the largest losses.^[27] Lumen Technologies fell 12.9% on the same day.^[28] Results did not hold the prices Four of the companies in this set reported results within a week of the sell-off. In each case the shares fell after the report. Intel reported third-quarter sales of $16.5 billion, up 21% from a year earlier.^[29] It forecast fourth-quarter revenue of $15 billion to $16 billion.^[30] Its shares fell nearly 23% after the forecast.^[31] OfficeChai put the fall at 28.6% on 30 October.^[32] Intel said it does not expect positive cash flow this year.^[33] It has committed about $20 billion in capital spending this year.^[34] It expects the slowdown in PC demand to last through the first half of 2027.^[35] An explosion at its Fab 28 plant in Israel on 14 October killed two people.^[36] The shutdown of that plant is expected to cut revenue by about $600 million.^[37] AMD held its third-quarter call on 3 November.^[38] It reported revenue of $13.4 billion.^[39] It said it expects revenue growth of more than 80% in 2027.^[40] It filed its quarterly report on 4 November.^[41] Its shares fell 17.3% on 5 November.^[42] Qualcomm released an earnings forecast below expectations.^[43] Its fiscal fourth-quarter revenue was $10.44 billion.^[44] Revenue from smartphone chips fell 26% from a year earlier.^[45] Revenue from car chips rose 89%.^[46] The company expects rising chip costs to squeeze profit until the April to September 2027 period.^[47] Its shares fell about 11% after the report.^[48] JPMorgan, UBS and Susquehanna cut their price targets.^[49] Lumen's revenue missed estimates and its earnings beat them.^[50] Third-quarter revenue was $2.72 billion, down 12% from a year earlier.^[51] Its strategic revenue grew 10%.^[52] That line is 55% of total revenue.^[53] Lumen carries $13.2 billion in gross debt and $11.3 billion in net debt.^[54] Set side by side, the four reports show revenue growth at Intel and a forecast of 80% growth at AMD. Both stocks still fell by double digits. The other two carried weaker numbers: profit guidance below expectations at Qualcomm and a 12% revenue decline at Lumen. In this set, growth in the quarter did not keep a chip stock from falling. One report in the same session went the other way. AppLovin rose 31% after it beat analysts' earnings estimates.^[55] Not all of technology Trefis reported that the selling hit AI builders and suppliers rather than all of big tech.^[56] Apple and Microsoft closed at 52-week highs on Wednesday, 4 November.^[57] The next day, the losses fell on chips, memory and AI cloud names.^[27] The political factor Democrats won control of the House and Senate in the midterm elections.^[58] The semiconductor sell-off followed those gains.^[59] Gina Hinojosa won the governor's race in Texas.^[60] She campaigned for a pause on new data centres.^[61] Investors priced in higher political risk for the construction of AI data centres, OfficeChai reported.^[62] Doubts also exist over whether AI infrastructure spending will pay off.^[63] Other markets The selling spread to Asia. South Korea's Kospi fell 5.3%.^[64] It fell more than 6% on 6 November.^[65] Japan's Nikkei 225 entered a bear market on 6 November.^[66] It fell more than 6% in early Friday trading.^[67] In India, GIFT Nifty was down about 188 points in early trade.^[68] Brent crude rose 3.9% to $98.29 a barrel.^[69] The 10-year US Treasury yield fell to 4.84%.^[70] The Bank of England raised its main interest rate for the first time in three years.^[71] The numbers ahead The spending behind these stocks remains large. JPMorgan estimates global AI spending at about $900 billion in 2026.^[72] It estimates $5.5 trillion in total through 2030.^[73] OfficeChai reported that commitments to the AI buildout remain large despite the sell-off.^[74] Nvidia reports earnings on Tuesday, 17 November.^[75] Nasdaq-100 futures rose 1.7% after the 5 November sell-off.^[76]