Optical networking equipment manufacturers are proving that there is still some steam left in their sector. Finisar's (Nasdaq: FNSR) better-than-estimated numbers added to the surprise the Street got after peer Ciena's (Nasdaq: CIEN) expectation-beating results. Though Finisar's first-quarter bottom line slumped 48%, the fact that the Street was expecting much lower numbers suggests how tepid the market’s view on the company -- or should I say the sector as a whole -- must have been.

What should Fools make of the numbers that seem ugly at first glance but still manage to impress the market?

Decoding the numbers
Finisar's revenue for the quarter rose by 9.8% from the year-ago quarter to $228.2 million. Lower demand from Chinese telecom customers dampened what could have been higher growth.

In spite of a growing top line, the California-based company's operating margin slipped to 4.5% from 11.4% in the year-ago quarter, the primary factor being higher R&D spending related to the acquisition of optical-components company Ignis. As a result, Finisar's bottom line fell to $10.1 million from $19.1 million a year ago.

The inventory game
It's worth noting the sudden dip in the demand for wavelength-selective switches (WSS) and reconfigurable optical add/drop multiplexer (ROADM) products. These products were the primary drivers for Finisar's revenues, when things suddenly took a turn in the past few months. In the fourth quarter, sales from these products fell 28.7% sequentially, and the trend continues, with sales again slipping sequentially by 4.2% in the just-concluded quarter.

There was speculation that customers already held large inventories, meaning new orders for suppliers like Finisar have not come easily. Finisar hasn't said much on the reasons behind the fall but did hint at customer issues.

An inventory-correction issue has been looming large over the industry. JDS Uniphase's (Nasdaq: JDSU) fourth-quarter revenues were also affected because of declining sales in some products resulting from customer inventory corrections. Same goes for the hit on Oclaro's (Nasdaq: OCLR) fourth-quarter revenues and margins. 

In such situations, I would prefer seeing higher revenues that justify the rise in Finisar's inventory levels, which have gone up by almost 35% in the first quarter. The company expects major growth to come from the aforementioned products in its next quarter, and it will be worth the wait to see whether its optimism turns true.

The Foolish bottom line
Two factors worth a wait-and-watch stance are how sales go both from China and for ROADM/WSS products. Another challenge facing Finisar is to manage R&D spending in a way so that operating costs are under control, thus pushing up income margins.

Again, we'll have to see how the Ignis acquisition adds to revenues in the coming quarters. Keeping all these factors in mind, I may wait for some more visibility before getting too upbeat about the stock. 

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