Coherent shares are selling off in sympathy with a broader downturn across the optical networking and hardware sector, as peers like Fabrinet and MACOM Technology Solutions also experienced significant declines. While the company recently reported strong fiscal Q1 2027 results featuring 50% revenue growth and an 80% surge in EPS, the stock is currently retracing following a 10% gain earlier in the week. This downward pressure appears to be a sector-wide cooling period rather than company-specific news, as investors weigh the risks of a potential regulatory crackdown on Chinese optical components that has recently impacted the broader industry.