Which S&P500 stocks are showing activity after the closing bell on Tuesday?

By Mill Chart - Last update: Feb 17, 2026

Let's have a look at what is happening on the US markets after the closing bell on Tuesday. Below you can find the top S&P500 gainers and losers in today's after hours session.


postmarket

Today's after hours gainers

TickerChangeComment
CDNS3.97%After the closing bell, CADENCE DESIGN SYS INC (NASDAQ:CDNS) demonstrated strong momentum in the after-hours session, with a 3.97% rise to $294.7. CADENCE DESIGN SYS INC released earnings Yesterday. Earlier today the company had a press release: Cadence Reports Fourth Quarter and Fiscal Year 2025 Financial Results.
STLD3.01%Positive market activity for STEEL DYNAMICS INC (NASDAQ:STLD) after regular trading hours, with a 3.01% increase to $197.7 in the after-hours session on Tuesday. In the last 3 months the share price increased with 21.35%.
SNPS2.68%SYNOPSYS INC's (NASDAQ:SNPS) stock price increased by 2.68% to $433.26. The stock is trading 30.43% lower than 6 months ago.
MOS2.27%MOSAIC CO/THE's (NYSE:MOS) shares rose 2.27% to $29.74 during Tuesday's after hours session. In the last 3 months the share price increased with 20.31%.

Our after hours gainers page will show you the full list.

Today's after hours losers

TickerChangeComment
ANET-6.44%ARISTA NETWORKS INC's (NYSE:ANET) shares experienced a 6.44% decrease to $133.4 in the after-hours session. Shareholders saw the stock price going 21.42% higher in the past 3 months.
PANW-5.44%PALO ALTO NETWORKS INC's (NASDAQ:PANW) stock price is declining with 5.44% to a price of $154.6. yesterday the company released their earnings.
AMD-3.88%ADVANCED MICRO DEVICES's (NASDAQ:AMD) stock price saw a decrease of 3.88% to $195.2 during Tuesday's after-hours session. Two days ago the company had a press release: AMD and TCS to bring state-of-the-art ‘Helios’ rack-scale AI architecture to India.
SNDK-3.66%The after-hours session reflects SANDISK CORP (NASDAQ:SNDK)'s ongoing correction after experiencing a %ABSPERF% loss in the regular trading hours. Shareholders saw the stock price going 42.79% higher in the past month.
HSY-2.19%HERSHEY CO/THE's (NYSE:HSY) stock price is showing a decline of 2.19% to a price of $214.59 during the after-hours session. The stock is trading 20.93% higher than 6 months ago.

Our after hours losers page will show you the full list.

MOSAIC CO/THE

NYSE:MOS (2/17/2026, 4:53:18 PM)

After market: 29.08 0 (0%)

29.08

-0.57 (-1.92%)


STEEL DYNAMICS INC

NASDAQ:STLD (2/17/2026, 4:53:34 PM)

After market: 191.92 0 (0%)

191.92

+0.24 (+0.13%)


HERSHEY CO/THE

NYSE:HSY (2/17/2026, 4:55:59 PM)

After market: 219.95 +0.55 (+0.25%)

219.4

-3.18 (-1.43%)


ADVANCED MICRO DEVICES

NASDAQ:AMD (2/17/2026, 4:58:03 PM)

After market: 195.67 -7.41 (-3.65%)

203.08

-4.24 (-2.05%)


SANDISK CORP

NASDAQ:SNDK (2/17/2026, 4:58:09 PM)

After market: 573.1 -17.49 (-2.96%)

590.59

-35.97 (-5.74%)


CADENCE DESIGN SYS INC

NASDAQ:CDNS (2/17/2026, 4:58:00 PM)

After market: 295 +11.54 (+4.07%)

283.46

-16 (-5.34%)


SYNOPSYS INC

NASDAQ:SNPS (2/17/2026, 4:57:27 PM)

After market: 432.88 +10.93 (+2.59%)

421.95

-15.14 (-3.46%)


PALO ALTO NETWORKS INC

NASDAQ:PANW (2/17/2026, 4:58:08 PM)

After market: 154.8 -8.7 (-5.32%)

163.5

-3.45 (-2.07%)


ARISTA NETWORKS INC

NYSE:ANET (2/17/2026, 4:58:04 PM)

After market: 135 -7.58 (-5.32%)

142.58

+0.99 (+0.7%)



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