Early movers: LEN, UA, TSLA, NRG, SNE, FSLR & more
Under Armour – Sterne Agee cut its rating on the athletic apparel maker's shares to "neutral" from "buy", after a year-to-date gain of 40 percent. However, the firm said its view of Under Armour's long term growth prospects remains intact.

ConAgra –The food producer reported fiscal third quarter profit of 62 cents per share, excluding certain items, beating estimates by two cents. ConAgra said it is dealing with "operating challenges" that have impacted earnings, but that it is encouraged by some "pockets of strength."

Lennar —The home builder reported fiscal first quarter profit of 35 cents per share, seven cents above estimates, with revenue above consensus as well. Lennar sold more homes at higher prices, although it said it is too soon to predict how well the spring home selling season will go.

Check out which companies are making headlines before the bell:

Tesla –Arizona is considering lifting its direct-sales ban on automobiles in the state, just days after New Jersey banned Tesla from selling directly to customers.

Ameren –Goldman Sachs downgraded the electric and gas utility to "sell" from "neutral" on a valuation basis, as well as citing lower than average near term dividend growth.

NRG Energy –Goldman upgraded the energy company's shares to "conviction buy" from "neutral", pointing to under-appreciated free cash flow, among other factors.

First Solar –Baird upped its price target for the solar equipment provider to $87 per share from $67 and repeated an "outperform" rating, saying First Solar is becoming even more efficient as it reduces costs and pushes new technology into the marketplace.

Sony –The electronics giant reportedly seeks to cut down on the number of suppliers in its network. Japan's Nikkei newspaper said the move is part of an effort to bring products to the marketplace faster.

Herman Miller –The maker of office furniture reported third quarter profit of 34 cents per share, in line with Street estimates, but forecast current quarter profit largely above Wall Street consensus. The company saw new orders rise 21 percent during the third quarter, with profit margins expanding as well.

Guess –The clothing maker earned 83 cents per share for the fourth quarter, beating estimates by three cents, with revenue beating forecasts as well. However, it also forecast an unexpected loss for the current quarter, saying customer traffic at its North American stores has been weak.

—By CNBC's Peter Schacknow

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