Corning's stock plummeted 5.11% intraday on Wednesday, giving back gains from a recent rebound as investors took profits.

The decline was driven by profit-taking as Corning's valuation remains elevated at approximately 100 times price-to-earnings, while the broader optical communications sector trades at the 99th percentile of its five-year valuation range, leaving minimal margin of safety. The sector-wide pressure was reflected in peer stock Coherent also falling on the same day.

Short-term capital opted to lock in profits ahead of Corning's next earnings report expected on July 28 pre-market, contributing to the selling pressure. The market is likely to remain volatile until fundamental performance is verified.