The S&P 500 fell 1.21% on Thursday 22 October, ending a three-day run of gains. The Nasdaq had its worst session since June. Meta's results showed its first cash outflow in over a decade, and Lam Research's warning on chip supply landed on top of that. Selling that had paused on Wednesday returned to AI hardware and power names, while a group of earnings reporters rose against the tape.
Chip Equipment After Lam
LRCX (-11.76%) closed at $230.15 after guiding December-quarter revenue to $8.6bn, plus or minus $400m. CEO Tim Archer said cleanroom space and component supply will cap chipmakers' output into 2027. Lam expects delayed shipments to move into the March quarter, so the first half of 2027 shows whether this was a timing slip. Three brokers cut targets and kept positive ratings.
Peers fell by similar amounts. KLAC (-9.55%) closed at $147.83, which makes its weekly loss 15.26%, and a Citi warning on component shortages had already weighed on it earlier in the week. TER (-10.63%) closed at $308.75 and Q (-9.48%) at $108.78. None has company news, and the sector explanation rests on secondary coverage. KLA reports on 28 October and Teradyne on 27 October.
Optics, Chips and Electronics
This is the optical slide that has run since 8 October, and Wednesday's bounce has been given back. COHR (-12.51%) closed at $207.82, down 28.49% over 20 sessions, with financing worries over AI build-outs the explanation on offer. LITE (-11.54%) closed at $752.54 and CIEN (-10.71%) at $322.64. The Ciena link to Meta and Lam comes from one aggregator headline, and the company reported no news.
MPWR (-8.99%) fell to $1,167.93 on 2.18x average volume, more than most chip peers, and no source explains the gap. KEYS (-8.74%) closed at $311.52, 20.1% below its 6 October high. FLEX (-11.08%) fell to $76.69 on 3.14x average volume, extending a slide that has cost it 22.14% since 15 October. Quiver Quantitative ties it to financing concerns over the Axiom spin-off. Flex reports on 28 October.
AI Power and Infrastructure
The power names that led the earlier AI trade fell alongside. GEV (-10.64%) closed at $827.42, its largest one-day drop in the window, on 2.66x average volume. Media commentary links it to Meta's negative free cash flow of $2.12bn, and GE Vernova made no statement. Vertiv fell 7.81% and Eaton 6.33%.
BE (-8.70%) closed at $217.77 before reporting. The numbers then beat: EPS of $0.94 against $0.69 expected, revenue of $1.24bn against $1.06bn, and full-year revenue guidance raised to $4.4bn to $4.6bn. The shares still slid about 4.5% after hours, and Stocktwits points to negative cash flow. VST (-9.81%) fell to $140.83 on 2.27x average volume with no confirmed trigger. PWR (-8.10%) took its weekly loss to 13.98%, and Quanta reports on 29 October.
Earnings Beats
Four reporters rose despite the weak market. ALLE (+11.02%) closed at $176.52 on adjusted EPS of $2.60 against $2.50 expected, and the company raised its full-year outlook to $9.05 to $9.10. ROP (+9.73%) closed at $436.23 on 2.6x average volume after adjusted EPS of $5.89 and a raised outlook. Most of its EPS growth came from a lower share count, and the stock was trading near 17x forward earnings before the release.
EFX (+6.59%) added an Argus upgrade to Buy to Tuesday's results jump, which brings its weekly gain to 16.05%. Management has cut its 2026 revenue midpoint, so the rally rests on margins. HAS (+2.83%) closed at $117.23, a new 52-week high and 19.12% above last week's close, after a 35.04% gain over 20 sessions.
One-Offs
MRNA (-17.57%) closed at $202.63 on 2.1x average volume. Phase 3 melanoma data leaked on social media ahead of ESMO and showed a 42% cut in recurrence or death, at the low end of the 40% to 50% range analysts expected. The stock had touched a 52-week high of $254.48 a day earlier, and analysts mostly call the fall sell-the-news. Biotech peers rose.
ACN (+7.69%) closed at $258.74, taking its weekly gain to 15.04%. No company trigger is confirmed. The IT services rotation that started last week and the China unit review are the only context, and the shares trade on 16.3x forward earnings.
What to watch
- 24 October: Moderna (MRNA) presents the full melanoma data at ESMO.
- 27 October: Teradyne (TER) reports after the close.
- 28 October: Flex (FLEX), GE Vernova (GEV) and KLA (KLAC) report.
- 29 October: Quanta (PWR) and Monolithic Power (MPWR) report.
- 4 to 6 November: Coherent (COHR) and Qnity (Q) on 4 November, Lumentum (LITE) on 5 November, Moderna and Vistra (VST) on 6 November.