Ciena beat on sales and earnings this morning.
Guidance for Q4, however, suggests gross profit margins may slip.
Ciena (NYSE: CIEN) stock tumbled 9.5% through 1:30 p.m. ET Thursday despite beating on earnings this morning.
Heading into the company's fiscal Q3 2026 report, analysts forecast Ciena would earn $1.72 per share (non-GAAP) on $1.63 billion in sales. In fact, Ciena earned $2.11 per share on $1.67 billion in sales.
Missed Nvidia in 2009? This Rare Signal Is Flashing Again. In 2009, a "Double Down" signal flashed for a little-known chipmaker called Nvidia. For the first time in years, that same "Total Conviction" signal is flashing for a company 1/100th the size of Nvidia. Continue »
So why aren't investors cheering Ciena's performance?
Image source: Getty Images.
Sales, after all, surged 37% year over year in Q3, and non-GAAP earnings more than tripled. Earnings calculated under generally accepted accounting principles (GAAP) weren't quite as good as the non-GAAP number, but at $1.83 per share, were still five times as much as Ciena earned in Q3 2025.
CEO Gary Smith called the company's performance last quarter "outstanding" and confirmed, "AI continues to drive compounding waves of network investment."
CFO Marc Graff predicted Ciena will deliver "increasingly profitable growth" as it expands its production capacity to support the AI revolution.
What does this mean for investors?
Ciena forecasts that it will deliver about $1.75 billion in revenue in Q4. Management didn't provide GAAP earnings guidance but noted that its gross profit margin for the quarter will be only about 45%. While that's within the margin of error for the 45.4% gross margin Ciena reported for Q3, it still suggests margins might dip slightly.
Is 40 basis points of gross margin slippage enough to explain the stock's near-10% sell-off today? Actually, it may be -- when you consider how priced for perfection Ciena stock already was. Valued at 120 times earnings, Ciena might be worth its price if it succeeds in averaging 75% annual earnings growth over the next five years, as Wall Street forecasts.
If margins suffer and Ciena's growth slows, however -- look out below.
Before you buy stock in Ciena, consider this:
The Motley Fool Stock Advisor analyst team just identified what they believe are the 10 best stocks for investors to buy now… and Ciena wasn’t one of them. The 10 stocks that made the cut could produce monster returns in the coming years.
Consider when Netflix made this list on December 17, 2004... if you invested $1,000 at the time of our recommendation, you’d have $446,157!* Or when Nvidia made this list on April 15, 2005... if you invested $1,000 at the time of our recommendation, you’d have $1,377,357!*
Now, it’s worth noting Stock Advisor’s total average return is 983% — a market-crushing outperformance compared to 212% for the S&P 500. Don't miss the latest top 10 list, available with Stock Advisor, and join an investing community built by individual investors for individual investors.
See the 10 stocks »
*Stock Advisor returns as of September 3, 2026.
Rich Smith has no position in any of the stocks mentioned. The Motley Fool has positions in and recommends Ciena. The Motley Fool has a disclosure policy.