Among the companies with shares expected to actively trade in Friday's session are Analogic Corp. (ALOG), Werner Enterprises Inc. (WERN) and Neuralstem Inc. (CUR).

Analogic's fiscal fourth-quarter earnings more than doubled, easily topping market expectations, as ultrasound and security-technology sales continued to show strength. Shares jumped 12% to $77.75 premarket.

Werner forecast fiscal third-quarter earnings below analyst expectations, noting its costs are rising faster than its revenue per mile. The outlook led to several downgrades from analysts, including those at Wells Fargo, which cited cost pressures last week in cutting its EPS target after meeting with management. But the reduction was "clearly not enough" in light of Thursday's announcement, the investment bank admitted as it downgraded Werner to market perform. The trucking company's shares sank 13% to $20.60 premarket.

Neuralstem plans to offer an undisclosed number of shares as it seeks to raise funds for general purposes, including research and development, working capital, capital expenditures and clinical trials. The biotechnology company had 54.1 million shares outstanding as of July 31. Shares were down 17% to $1.15 premarket.

Silver and gold miner Golden Minerals Co. (AUMN, AUM.T) said it is selling 5.5 million units--comprised of one share of common stock and a five year warrant to acquire half of a share of common stock at an exercise price of $8.42--at a price of $5.75 per unit, for gross proceeds of $31.6 million. The company had 35.7 million shares outstanding as of Aug. 3. Shares were down 15% to $5.99 premarket.

Spirit Airlines Inc. (SAVE) is cut to market perform from outperform by Raymond James, which cites weakness in some booking channels causing unit revenue for the low-cost U.S. carrier to track lower than expectations. "This is the fourth quarter in a row where we and the Street have overestimated Spirit's profitability and earnings predictability, and it appears that the business may not have the margin expansion opportunity we had previously anticipated," the firm said in a note to clients. Shares fell 4.3% to $18.82 premarket.

RealPage Inc. (RP) said certain shareholders are offering four million shares of the software company's stock. RealPage had about 73.7 million shares outstanding at the end of June. Shares dropped 3.9% to $25.01 in premarket trading.

Health insurer UnitedHealth Group Inc. (UNH) will replace food giant Kraft Foods Inc. (KFT) in the Dow Jones Industrial Index after trading closes Sept. 21. UnitedHealth shares rose 2.5% to $55.25 premarket, while Kraft fell 0.6% to $39.91.

 
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CompuCredit Holdings Corp. (CCRT) said its offer to buy back as much as 8.25 million of its shares at a significant premium was oversubscribed.

Covidien PLC (COV) projected annual sales to grow between 3% and 6% in its upcoming fiscal year and said plans to spin off its pharmaceuticals business into a standalone public company were on track.

Delphi Automotive PLC (DLPH) authorized $750 million in share repurchases, as the auto-parts maker looks to increase shareholder returns.

Semiconductor company RDA Microelectronics Inc.'s (RDA) board declared its first special dividend, citing a strong balance sheet and revenue growth.

Syswin Inc.'s (SYSW) board has set up a special committee to evaluate the chief executive's proposal to take the Chinese real-estate company private.

Textainer Group Holdings Ltd. (TGH) said an offering of 7.5 million common shares priced at a 1.6% discount to Thursday's closing price.

Valeant Pharmaceuticals International Inc. (VRX) said its president, Rajiv De Silva, will be leaving the company after the close of its acquisition of Medicis Pharmaceutical Corp. (MRX) to pursue other interests.

WageWorks Inc. (WAGE) and certain shareholders are offering a total of around $100 million of WageWorks shares. The company recently had a market capitalization of roughly $460 million, according to FactSet.

Hard-disk-drive maker Western Digital Corp. (WDC) cut its revenue outlook for the fiscal first quarter, while at the same time initiating a quarterly dividend and boosting its share buyback authorization by $1.5 billion.

Write to Anna Prior at anna.prior@dowjones.com

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