Ciena stock tumbles 14% as AI-networking names retreat — what investors watch next
New York, Jan 8, 2026, 13:42 EST — Regular session Ciena Corp shares were down about 14% at $222.73 on Thursday, after ending Wednesday at $259.27 and touching $260 earlier in the session. Roughly 2.8 million shares had changed hands by early afternoon. Optical peer Lumentum Holdings fell about 11% and Coherent slid roughly 9%, while Arista Networks was down about 5%.