Seven of the worst performers for the month were still up by triple digits for 2026

Some of the hottest semiconductor stocks of 2026 have been among July's biggest decliners.

Early on Friday, the PHLX semiconductor index was down 4.8%, making for a decline of nearly 21% for July, after this index of 30 chip makers and related suppliers had doubled during the first six months of 2026.

To compile a list of the large-cap technology stocks that have fallen the most during July, we began with the components of:

-- The S&P 500 SPX,

-- The iShares Semiconductor ETF SOXX, which holds all 30 stocks in the PHLX Semiconductor Index SOX, and

-- The Invesco QQQ Trust QQQ, which holds the component stocks in the Nasdaq-100 Index NDX, which is made up of the largest 100 nonfinancial companies in the full Nasdaq Composite Index COMP.

After removing duplicates of stocks in two or more of the groups, our initial list was made up of 523 stocks.

Based on share prices at 9:45 Eastern time on Friday, these 18 stocks were showing July declines of at least 30%, according to data provided by LSEG. The list also includes year-to-date price changes, current forward price-to-earnings ratios and P/E ratios at the end of 2025.

 
Company                        July 16 price change  July price change  2026 price change  Intraday forward P/E  Forward P/E as of Dec. 31 
Corning                                       -7.1%             -42.4%                68%                  38.0                       28.2 
Sandisk                                       -5.5%             -41.4%               462%                   6.3                       13.6 
Marvell Technology                            -4.8%             -39.8%               111%                  34.8                       24.0 
Astera Labs                                   -9.0%             -39.7%                75%                  76.2                       70.5 
Nebius Group                                  -2.6%             -39.4%               100%                   N/A                        N/A 
Teradyne                                      -7.3%             -38.3%                54%                  34.1                       36.7 
Rocket Lab                                    -3.6%             -36.1%                -7%                   N/A                        N/A 
Intel                                         -7.4%             -35.7%               143%                  62.8                       61.2 
Coherent                                      -7.6%             -35.1%                39%                  28.8                       31.7 
Macom Technology Solutions                    -6.8%             -32.5%                50%                  38.6                       38.4 
Western Digital                               -7.6%             -32.5%               150%                  20.5                       19.6 
KLA                                           -6.1%             -31.7%                70%                  38.9                       31.0 
Flex                                          -8.0%             -31.2%                84%                  20.7                       17.4 
Credo Technology Group                       -10.1%             -31.2%                30%                  27.2                       42.6 
Arm Holdings                                  -6.8%             -31.1%               123%                 100.5                       51.2 
CoreWeave                                     -6.0%             -31.1%                -4%                   N/A                        N/A 
Lam Research                                  -6.8%             -31.0%                75%                  36.3                       32.1 
Micron Technology                             -5.3%             -30.0%               183%                   5.4                        7.9 
                                                                                                                              Source: LSEG 

The forward P/E ratios are based on prices and rolling consensus 12-month earnings-per-share estimates among analysts polled by LSEG. They compare with weighted forward P/E ratios of 22.8 for SOXX, 20.3 for the SPDR S&P 500 ETF Trust SPY and 22.8 for QQQ, as calculated by LSEG as of Thursday's close.

Seven of these stocks are still up by triple digits this year, despite the large declines during July. The best performer of all so far in 2026 has been Sandisk $(SNDK)$, with a 462% gain. And this stock's forward P/E has declined to a low 6.3 from 13.6 at the end of last year, because the rolling consensus EPS estimate has increased more quickly than the share price.

This is also true for Micron $(MU)$, whose stock is down 30% for July but still up 183% for 2026, as its forward P/E has declined to 5.4 from 7.9 at the end of last year.

The low forward P/E ratios for Sandisk and Micron haven't only resulted from the hot market for memory chips and computer memory peripherals. They also reflect the wariness of some investors about the cyclicality of this industry. As recently as three years ago, Micron reported a 49% decline in revenue for its fiscal year that ended Aug. 31, 2023.

Related coverage:

-- Semiconductor stocks are on the verge of a bear market. Is the thrill in the chips trade gone?

-- As semiconductor stocks slump, one AI-adjacent sector is thriving - and these are the stocks to buy there

-- Micron has turned into 'the most important stock in the market.' So is it time to worry?

-- What the launch of SK Hynix leveraged ETFs tells us about the hottest trade on Wall Street

-- Sandisk's stock is plunging, but some analysts are getting even more bullish

Don't miss: How this small-cap stock picker's 'ownership' approach has helped him beat the Russell 2000

-Philip van Doorn

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(END) Dow Jones Newswires

July 17, 2026 10:40 ET (14:40 GMT)

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