Coherent's AI Optics Business Is Scaling-So Why Does the Stock Keep Missing?

Coherent is posting AI-era growth, but the market still values it like an old-line industrial

Coherent's recent results look more like a scaling photovoltaics business than a mature industrial name. In the September quarter, the company reported 19% year-over-year pro forma revenue growth. By the March quarter, that pace accelerated to 27% pro forma growth, and management tied both quarters to demand from AI datacenters and communications. The disconnect is simple: the business is expanding, yet the stock still trades as if investors are waiting for proof that the mix shift is real.

Why the market still hesitates

Coherent has spent years judged by its older cycle profile. Investors still associate it with volatility, balance-sheet repair, and execution swings, so strong quarters are often treated as tests rather than evidence of a durable change. That caution can make sense, but it also creates a reaction lag: the business improves before the market fully changes how it values that improvement.

The core bull case is that the mix is shifting toward higher-value AI-optics content, which should support not only growth, but earnings quality. In the September quarter, Coherent posted GAAP gross margin of 36.6%. By the March quarter, revenue had risen to $1.81 billion, with GAAP gross margin of 37.7% and non-GAAP EPS of $1.41. That is not just a one-quarter bounce. It is a business showing better scale and better profitability at the same time.

The bear case is also straightforward: connectivity demand can be lumpy, and one string of good quarters does not fully rewrite the valuation model. But that is precisely why the stock remains interesting. If the trend continues, the market may be repricing the name late rather than early.

The financial trend is clear, which is why the debate has shifted

The question is no longer whether Coherent is improving. It is. The more useful question is whether investors are finally starting to treat that improvement as something more durable than another cyclical upside quarter.

In the September quarter, revenue was $1.58 billion, up 19% year-over-year on a pro forma basis. GAAP gross margin was 36.6%, and non-GAAP gross margin was 38.7%. In the March quarter, revenue increased to $1.81 billion, up 27% on a pro forma basis. GAAP gross margin reached 37.7%, and non-GAAP gross margin reached 39.6%. Those results support a simple conclusion: Coherent is posting faster growth while gross profitability continues to improve.

What investors are still waiting to confirm

Even with that progress, sentiment has not fully rerated the stock. The likely reason is that investors still want more proof that the latest demand environment is translating into a more stable earnings profile rather than just another strong cycle window.

That caution matters because the next few updates should clarify whether management's demand commentary is holding up. So far, the company has pointed to strong demand from AI-related datacenters and communications, and later to exceptionally strong demand across our datacenter and communications businesses. Bulls read that as evidence of a lasting AI-optics trend. Bears see the need for more quarters of confirmation.

What would make the repricing more credible

The case gets stronger if future results show several things at once:

• Demand commentary stays firm. Management continues linking growth to AI infrastructure spending instead of using softer language around datacenter and communications demand.
• Margins hold up. Recent gross-margin gains remain in place as revenue keeps scaling.
• Profitability improves alongside growth. Higher revenue translates into better EPS and cash generation, not just a temporary mix tailwind.
• Balance-sheet progress continues. Debt reduction and refinancing benefits keep reducing an old source of investor skepticism.

If those signals start showing up together, the market is more likely to stop treating Coherent as an industrial name that happened to post a few good quarters and start valuing it as a higher-quality AI optics platform. If another solid update is still dismissed as cyclical luck, the stock may continue underperforming even as the business improves.