Key Highlights

● Corning closed at $123.99 on October 22 as optical stocks fell with AI hardware.

● Corning is a major maker of optical fiber and cable alongside specialty glass.

● Amphenol, Keysight and Arista Networks all fell sharply.

● The S&P 500 posted 40 new 52-week highs against four new lows.

Corning (NYSE:GLW) tumbled on Thursday, October 22, 2026, closing at $123.99 as optical stocks joined the broad retreat in AI hardware on the S&P 500. Market data showed a selloff in optical names as the driver. Corning released no company-specific news.

Corning is best known for specialty glass, but it is also a major maker of optical fiber and cable. Data centers built for AI need huge amounts of fiber to connect servers, which has made Corning part of the AI infrastructure trade. That connection cut the other way on Thursday.

Meta's numbers changed the mood

The day's selling traced back to the third-quarter report from Meta Platforms (NASDAQ:META) on Wednesday evening. Meta posted record revenue of $64.60 billion, but it narrowed its 2026 capital spending range to $135 billion to $145 billion, raising the low end. Free cash flow was negative $2.12 billion, its first cash outflow in more than a decade, according to market data. Spending commitments rose to about $825 billion from about $700 billion in July, according to market data.

The worry for suppliers like Corning is that the biggest AI buyers may find their spending plans harder to finance. Meta's chief financial officer said Meta does not "have any specific financing plans to announce at this time."

Chip warning and Nvidia's remarks

Lam Research (NASDAQ:LRCX)'s guidance, with a midpoint slightly below consensus and citing supply constraints, hit chip and equipment stocks. The Philadelphia Semiconductor Index had its biggest one-day drop since June 23.

Nvidia (NASDAQ:NVDA)'s chief executive said, "The demand of the capital is much greater than the availability of the capital." Nvidia was one of the biggest drags on the S&P 500, according to market reports.

Corning had company. Amphenol (NYSE:APH), Keysight (NYSE:KEYS) and Arista Networks (NYSE:ANET) all fell sharply. Dell Technologies (NYSE:DELL) and Super Micro Computer (NASDAQ:SMCI) gave back Wednesday's gains. The S&P 500 technology sector was among the weakest of the day.

A divided market

The S&P 500 fell 93.74 points to 7,663.43, its worst day since July. The Nasdaq Composite lost 694.00 points to 26,008.86, its steepest drop since June 5, and about $1 trillion in market value, according to market data. The Dow Jones Industrial Average edged up 11.89 points to 52,867.98.

The broader market held up better than those numbers suggest. About two of every three S&P 500 stocks rose, according to market reports, and the S&P 500 posted 40 new 52-week highs against four new lows, according to market data. Consumer staples had their best day since April 2025, while health care hit a record. Homebuilders rallied as the 10-year Treasury yield fell back below a closely watched threshold for the first time since September 22.

Corning Waits on Data-Center Build Plans

Hyperscaler earnings will show whether data-center spending remains intact. Microsoft (NASDAQ:MSFT) and Alphabet (NASDAQ:GOOGL) report on October 28, and Amazon (NASDAQ:AMZN) reports on October 29. Their plans for new data-center capacity will matter for demand for optical fiber and connectivity.

The Federal Reserve announces its rate decision on October 28 after a two-day meeting, with third-quarter GDP and September PCE inflation data due on October 29.

Investors will also watch whether the optical-networking group can steady after Thursday's sharp drop, or whether the AI hardware retreat continues into Friday's session.