Coherent Corp. shares fell 5.4% in morning trading on Wednesday, dropping to $319.94 from a previous close of $338.36.

The decline followed a period of strong gains for the stock, which rose more than 10% on October 1 after Bernstein initiated coverage with an Outperform rating and a $350 price target. The firm positioned optical-module suppliers as beneficiaries of growing AI infrastructure spending.

Options market activity on October 5 showed put volume in COHR running at roughly 1.6 times its expected pace. December 2026 340-strike puts were among the most actively traded contracts during that session.

Insider filings around the same period showed stock sales by the company's chief technology officer and a board director.