Coherent's Rally Had Early Clues, but the Latest Quarter Raised the Bar

Coherent shares gained 135.4% in the 12 months through October 12, far ahead of the S&P 500's 17.3% return. The move looked sudden in the stock chart, but the operating improvement began appearing in filings well before the rally.

Revenue growth accelerated to 28% in the fiscal first quarter of 2025 from 9.1% in the prior quarter, while management pointed to a wider non-GAAP gross margin. Operating margin later reached 10.1%, compared with 5.9% in the quarter reported in August 2024. By August 2025, the company had also reduced its leverage ratio to 2.0 times from 2.5 times.

The evidence was not uniformly bullish. Revenue growth slowed to 23.9% and then 16.4% in the following reports, and operating margin eased to 9.5%. Investors who noticed the early turn still had to judge whether demand for optical components used in data centers would reaccelerate.

Coherent's official fiscal fourth-quarter 2026 results show that it did. Quarterly revenue reached $2.05 billion, up 34%, while GAAP gross margin was 38.5% and non-GAAP gross margin was 40.2%. Non-GAAP earnings were $1.74 per share. Management attributed the strength to data-center and communications demand and continued capacity expansion.

That newer evidence explains why the stock rerated, but it also raises expectations. A business priced for sustained AI infrastructure spending has less room for a capacity delay, customer digestion period or margin reversal. Revenue growth alone is not enough if capital spending absorbs the resulting cash.

The next useful evidence is whether Coherent can keep gross margin near current levels while converting its expansion into operating cash flow. The early clues were real, but the investment question has changed. Investors are no longer waiting for confirmation of demand; they are testing how much durable profit and cash that demand can produce.