Coherent (COHR) Drops 12.4% as Optical AI Premium Unwinds

Coherent opened the session at $383 and spent the day in a steady retreat, with shares sliding to around $335 by mid-afternoon. The move erases the premium that buyers assigned to the stock last week, when optimism around datacenter optical components had been driving the name higher. The sell-off is sharp enough that it raises an immediate question about whether something has changed in the underlying demand story or whether this is a one-day repricing after a run that got ahead of itself.

The timing adds an extra layer of significance because Lumentum, one of Coherent's closest peers in the optical networking space, is due to report results by Tuesday's close. If Lumentum's numbers and guidance hold up, today's move starts to look company-specific. If Lumentum also disappoints or pulls back, it would suggest the pressure is running across the whole datacenter optics segment rather than sitting with Coherent alone. Investors in either name will have a cleaner read on the sector's health within the next trading day.

For now, the chart tells a story of consistent selling pressure throughout the regular session with no meaningful bounce gaining traction. That kind of price action, without a clear intraday recovery, tends to signal that sellers were in control from the open rather than reacting to a single midday headline.