Why Is Coherent (COHR) Stock Down 4.83% Today, Oct 15? Optical Sector Selloff and AI Financing Concerns Weigh on Shares

Coherent (COHR) fell 4.83% to $250.60 on October 15, 2026, as investors rotated out of AI optical-hardware shares while higher rates sharpened scrutiny of data-center spending. This daily outlook examines the two pressure points, the main risks, and the technical levels that could shape the next move.