S&P 500 Closes Up 0.89% as Memory Stocks Reprice and Software Gets Sold

S&P 500 close: 7,509.20 (+0.89%) Nasdaq close: 25,837.21 (+1.29%) Sentiment: bullish

The S&P 500 closed at 7,509.20 on 21 July 2026, up 0.89%, as AI-driven DRAM and NAND contract pricing lifted memory and storage names and pulled the wider semiconductor group with them. Aehr Test Systems AEHR.US rose 27.86% to $98.91 after Craig-Hallum lifted its target to $125 from $68 on fiscal 2027 revenue guidance of $130m to $150m against roughly $85m of consensus. The advance snapped a three session losing run and took the VIX down 8.58% to 17.05.

What moved the index

• Technology: XLK.US +2.89%, worth roughly 87 bps of the 89 bps index move at a sector weight near 30%. Memory and storage did nearly all of it: SNDK.US +14.27%, WDC.US +12.51%, MU.US +12.17%, STX.US +11.14%.
• The eight sectors outside technology, communication services and staples: about +0.3% on roughly 55% of index weight, worth ~16 bps. The Russell 2000 closed +1.53%, so participation reached well past the largest names.
• Communication services: XLC.US -0.69%, about -7 bps, with GOOGL.US -1.38% into its Wednesday result.
• Consumer staples: XLP.US -0.94%, about -5 bps, the weakest of the eleven sectors as money moved toward risk.

Together these account for roughly 91 bps against the 89 bps the index moved, so nothing material sits outside the four.

Session highlights

• SMH.US +4.52% against IGV.US -1.25%, a 5.77 point gap between semiconductors and software inside the same sector.
• MU.US +12.17% to $970.82, WDC.US +12.51% to $548.39 and STX.US +11.14% to $891.83, after conventional DRAM contract prices rose as much as 95% in the first quarter and NAND prices climbed in each quarter since. Western Digital and Seagate have sold out 2026 hard drive capacity to AI data centres.
• 12,356.16 closed the Philadelphia Semiconductor Index, up 5.21% and still 15.57% under its 22 June peak of 14,634.72. Tuesday's 612 point gain recovered about a fifth of that drawdown.
• INTC.US +8.64% and AMD.US +8.11% both outpaced NVDA.US +1.97%. Buyers went to the semiconductor names that had lagged.
• MSFT.US -1.13%, GOOGL.US -1.38% and AMZN.US -0.98% each fell while the index gained 0.89%, and the S&P 500 still finished 63.20 points under its 15 July level of 7,572.40.
• 7,470.75 marked the session low inside the first hour. The index then climbed for the rest of the day and closed 5.6 points off its 7,514.80 high.

Sector scorecard

• Best: Technology (+2.89%)
• Worst: Consumer staples (-0.94%)
• Dispersion (best minus worst): 3.83 pts
• 7 of the 11 sectors closed higher. Technology split internally, with semiconductors at +4.52% and software at -1.25%.

Top movers

Notable announcements

• DHR.US -10.99% to $179.01 despite Q2 adjusted EPS of $1.94 beating $1.84 consensus on revenue of $6.27bn. Danaher trimmed 2026 core revenue growth to 3% to 4% from 3% to 6% and reported an 18% adjusted operating margin, down 9.3 points year on year.
• MSCI.US -10.14% to $561.74 on Q2 non-GAAP EPS of $4.94 against $4.98 consensus, with revenue of $867m up 12.2%. The company lifted its 2026 operating expense range to $1.54bn to $1.58bn.
• VICR.US -7.05% to $214.70 even after Q2 revenue of $143.4m rose 26.9% sequentially, gross margin reached 58% and Vicor raised its 2026 outlook above $600m.
• MMM.US +7.32% to $170.76 and GM.US +4.91% to $79.52, both on second quarter beats reported before the open.
• HAL.US -5.47% to $33.19, also on a second quarter that beat consensus before the open.
• TXN.US +2.55% to $291.30 after Susquehanna raised its target to $340 from $300 ahead of Wednesday's result.

DHR.US, VICR.US and HAL.US all beat on the reported quarter and all three closed lower, while MSCI.US missed by four cents and lost 10.14%. The selling keyed off forward cost and revenue guidance rather than the headline print.

After the closing bell

No S&P 500 company reported after Tuesday's close. Sub $10 names ran the after hours tape instead, with Antelope Enterprise AEHL.US and Core AI Holdings CHAI.US leading gainers and Ohmyhome OMH.US and Faraday Future FFAI.US leading decliners. None of them are index members. Four of the index's larger names report Wednesday after the bell.

Next session catalysts (ET)

• Wed, after close: TSLA.US second quarter, consensus $0.44 EPS on $25.24bn revenue against $0.40 and $22.50bn a year earlier.
• Wed, after close: IBM.US second quarter, consensus $3.02 EPS on $17.86bn revenue against $2.80 and $16.98bn a year earlier.
• Wed, after close: NOW.US, TXN.US and Alphabet GOOGL.US also report, so five index members land in the same evening.
• Thu 08:30: initial jobless claims, with Bloomberg Economics at 208k.
• Thu 10:00: new home sales, expected near 600k annualised, which would mark the slowest June in four years.

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