Ciena is trading 10.01% down at $360.30, as industry-wide concerns about financing and the sustainability of AI spending weigh on optical-networking and AI-infrastructure stocks. - The broader market is sharply lower, with technology shares under pressure. - Hotter-than-expected September inflation is weighing on technology and growth shares, while higher yields revive rate-hike concerns. - No clear new Ciena-specific catalyst has been identified; the move points to industry-wide and macroeconomic pressures rather than a company announcement.