Ciena is trading 6.4% down at $254.83 amid broader pressure on AI- and data-center-linked stocks. - Reuters reported November 5 that AI- and data-center-linked stocks slipped amid investor concerns a Democratic sweep could bring tougher scrutiny and slow data-center expansion. - Ciena had already fallen 9.28% on November 4, closing at $272.24; the current move extends that weakness. - No clear Ciena-specific catalyst was identified; supplied price context reflects the live move, and external price reports were not used for these figures.