Corning tumbled 18% on Tuesday after its second-quarter earnings beat—$0.78 EPS and $4.74B revenue against estimates of $0.75 and $4.62B—because third-quarter guidance disappointed. The company guided Q3 sales to $4.9B–$5.0B and core EPS $0.85–$0.89, implying 16% sales growth and 28% earnings growth. Wall Street had expected $4.99B and $0.85 EPS.
The miss was attributed to signals of weakened capex from wireless carriers and raised investor concerns about near-term demand for optical fiber and networking gear, despite Corning's $20B annualized sales target by Q3 2026. The optical segment—its star performer—grew sales 32% to $2.07B and Enterprise Networks within it rocketed 65%, but the forward-looking caution sparked a broader selloff.
The move dragged down optical stocks across the board: Lumentum retreated 4.7%, Coherent shed 5.7%, and Ciena lost 5.9%. The sell-off reflects profit-taking after a historic rally and signals investors are reassessing whether AI infrastructure capex can sustain consensus growth forecasts.
For architects and operators tracking the data center buildout, Corning's guidance cut is a signal to watch hyperscaler spending patterns closely. Even fundamentally strong units with Amazon and NVIDIA multiyear agreements can slide on near-term slowdown signals, marking a shift in sentiment from supply-chain euphoria to ROI scrutiny.