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Ciena –The telecom equipment maker reported third quarter profit of 32 cents per share, excluding certain items, four cents above estimates. Revenue also beat consensus, but the company gave a current quarter forecast below Street estimates based on "several significant variables."

D.R. Horton –The home builder's stock was upgraded to "buy" from "neutral" at UBS, which said the company is well-positioned heading into the next stage of the housing recovery.

Joy Global –The mining equipment maker missed estimates by four cents with third quarter profit of 80 cents per share, excluding certain items. Revenue was also well below forecasts in what Joy Global calls a "challenging commodity market environment" as customers cut their equipment spending.

Check out which companies are making headlines before the bell:

Mattress Firm–The mattress retailer earned 61 cents per share for the second quarter, excluding certain items, one cent above estimates. The company also announced it is buying West Coast bedding retailer Sleep Train for $425 million.

Stratasys–Morgan Stanley initiated coverage on the 3-D printer maker with an "overweight" rating, saying it's the best positioned in the industry to take advantage of a growing market over the next year.

Home Depot–The home improvement chain said it is still trying to gather the facts on a potential data breach. However, cybersecurity expert Brian Krebs said data may have been stolen from .

Foot Locker–Jefferies initiated coverage on the athletic apparel and footwear retailer with a "buy" rating, on the basis of "meaningful competitive advantages."

GoPro–JPMorgan Chase downgraded the high definition camera maker's shares to "neutral" from "overweight" on a valuation basis, after GoPro more than doubled from its IPO price of $24 per share.

Yum Brands–The company said it expects a 13 percent drop in same-restaurant sales in China for its third quarter, although it added that sales in that country are beginning to rebound. Yum was impacted by a food safety scare in July that also impacted companies like McDonald's.

PVH Corp.–PVH reported second quarter profit of $1.51 per share, excluding certain items, eight cents above estimates. The clothing maker was helped by growth in its Calvin Klein and Tommy Hilfiger brands, among others, but did lower its revenue outlook for the year amid increasing promotional activity.

H&R Block–The company lost 40 cents per share for its first quarter, matching estimates, with revenue coming in above forecasts. The tax preparation firm normally generates most of its earnings in the final half of its fiscal year, which includes tax season.

Tibco Software–Tibco is reviewing various strategic options, and has hired Goldman Sachs, among others, to assist in the process.

Shoe Carnival–The shoe retailer missed estimates by two cents with second quarter profit of 13 cents per share, with revenue below estimates as well. Shoe Carnival also gave a current quarter outlook that falls below analyst estimates, with store traffic remaining "soft."

Norwegian Cruise Line–The cruise line operator's stock was downgraded to "neutral" from "buy" at Goldman Sachs.

—By CNBC's Peter Schacknow

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