Corning's stock experienced a significant pre-market plunge of 5.14%, extending a period of recent weakness for the optical communications specialist.

The sharp decline reflects persistent market concerns that Meta's plan to sell idle AI computing capacity could signal cloud hyperscalers scaling back their optical communications capital expenditure, which would directly impact Corning's core business. Additionally, the stock faces pressure from reports of dense insider selling by executives and its elevated valuation, with a price-to-earnings ratio near 100x that far exceeds the optical communications industry's typical range of 15-25x.

Further contributing to the negative sentiment is ongoing profit-taking pressure from accumulated gains and bearish positioning in the options market, where significant out-of-the-money call sales suggest traders expect limited upside potential for the stock in the near term.