On September 28, Lumentum declined 3.13% in regular trading, trading at $907.64/share, with turnover of $691 million. The stock retreated sharply from its recent high near $958, erasing gains accumulated earlier in the week.

The decline came amid a broad selloff across the optical communications and semiconductor sectors. Corning fell over 3%, Coherent dropped more than 2%, and Marvell Technology slid over 3%, while Qualcomm and ARM each tumbled over 7%. The sector-wide weakness was triggered in part by reports that SCHMID is collaborating with core suppliers of Intel, NVIDIA, and AMD to co-develop glass substrate equipment, signaling that NVIDIA is accelerating efforts to resolve upstream bottlenecks in glass substrate manufacturing. This development raised concerns that a technology shift toward glass substrates could disrupt existing optical interconnect supply chains.

Earlier in the week, Lumentum had rallied nearly 5% after showcasing a high-density optical die-to-die interconnect solution with Qualcomm and Corning at ECOC 2026, and Citi had raised its target price to $1,400 with a buy rating. Despite favorable near-term fundamentals, the broader risk-off tone across tech and semiconductor names weighed heavily on the stock.

(The above content is based on publicly available market information, generated by a program or algorithm, and is intended solely as a stock movement alert. It does not constitute investment advice or a basis for trading decisions.)