Among the companies with shares expected to actively trade in Friday's session are Zynga Inc. (ZNGA), Starbucks Corp. (SBUX) and Expedia Inc. (EXPE).

Zynga's second-quarter loss narrowed as the social-game maker slashed expenses, though the number of daily active users slumped, resulting in far fewer bookings. Shares fell 18% to $2.87 premarket as the company guided for a wider-than-expected third-quarter loss and lower-than-expected bookings.

Starbucks's fiscal third-quarter earnings jumped 25% as the coffee giant booked same-store sales growth across all its regions. Shares climbed 6.9% to $72.88 in premarket trading as results topped Wall Street estimates and the company again raised its full-year earnings guidance.

Expedia's second-quarter earnings fell 32% as the online travel agent reported higher costs that offset growth in revenue. Expedia shares fell 23% to $49.77 premarket following the weak second-quarter results and lowered guidance.

Activision Blizzard Inc. (ATVI) said it reached an agreement to buy back nearly $6 billion worth of Vivendi SA's (VIV.FR, VIVEF) holding in the company, ending months of negotiations over the fate of the videogame giant. Shares rose 18% to $17.89 premarket after Activision said it will buy 429 million shares for about $13.60 per share, reducing conglomerate Vivendi from being majority shareholder.

Amazon.com Inc. (AMZN) swung to a surprise second-quarter loss as the Internet retail heavyweight's expansion plans continued to weigh on results, though revenue kept strengthening and was in-line with Wall Street views. Shares slipped 1.2% to $299.63 premarket.

Gilead Sciences Inc.'s (GILD) second-quarter profit rose 8.6% as the drug company posted sales gains from its core business of antiviral HIV treatments and made continued progress in its expansion into other disease areas. Shares rose 5.6% to $64.25 premarket.

Pearson PLC (PSO, PSON.LN) said it would continue to restructure to sharpen its focus on digital education and high-growth markets, as part of which it will look at a possible sale of Mergermarket. American depositary shares rose 7.8% to $20.92 premarket.

Oil-services company Halliburton Co. (HAL) is launching a $3.3 billion Dutch auction through which the company intends to repurchase some 8% of its stock at a price probably above Thursday's close. The company also agreed to plead guilty to destroying evidence in the wake of the Deepwater Horizon disaster in April 2010, the U.S. Justice Department announced Thursday. Shares rose 4.7% to $46.42 premarket.

Outerwall Inc.'s (OUTR) second-quarter profit rose a better-than-expected 27%, but revenue fell short of the formerly named Coinstar's own estimate. Shares fell 8.1% to $60.00 premarket as the company also guided for current-quarter earnings below analyst estimates.

Qlik Technologies Inc.'s (QLIK) second-quarter loss widened as an increase in costs masked revenue growth. Shares of Qlik, which sells software to midsize and large enterprises that allows businesses to search and query business data, were down 5.1% premarket to $30.00 as the company cut its full-year earnings guidance.

SolarWinds Inc.'s (SWI) investors ignored a 17% jump in the company's second-quarter profit, as the information-technology management software firm's shares fell on disappointing guidance commentary. The stock slumped 21% to $36.25 in premarket trading, as SolarWinds issued a weak outlook for the third quarter and trimmed expectations for the full year.

Tempur Sealy International Inc. (TPX) swung to a second-quarter loss on acquisition-related charges as the mattress company reported its first full quarter to include results from its March acquisition of Sealy Corp. Shares fell 12% to $37.00 premarket as the results missed expectations and Tempur Sealy cut its 2013 guidance.

Vertex Pharmaceuticals Inc. (VRTX) said the U.S. Food and Drug Administration has put a partial clinical hold on a mid-stage study of its experimental hepatitis C treatment VX-135 because of toxicity concerns. Shares were down 8.7% to $80.00 premarket.

 
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Carmike Cinemas Inc. (CKEC) said its offering of 4.5 million shares priced at $12 a piece, a 3.7% discount to its Thursday closing price. The movie theater operator had 17.9 million shares outstanding as of July 19.

CBS Corp.'s (CBS, CBSA) board has authorized a sharp increase in the amount of shares the media company can repurchase, adding $5.1 billion to the program.

Cerner Corp.'s (CERN) second-quarter earnings rose 15% as the hospital-information technology vendor reported stronger sales and margins and bookings climbed.

Cliffs Natural Resources Inc.'s (CLF) second-quarter profit declined 43% as the mining company's revenue was stung by weaker iron-ore pricing, while the bottom line was also hurt by an investment write-down charge.

Deckers Outdoor Corp.'s (DECK) second-quarter loss widened as the footwear maker recorded a decline in UGG and Teva brand sales as well as weaker margins. Revenue fell short of the company's projections.

Dole Food Co.'s (DOLE) second-quarter earnings soared from a year earlier as the fresh fruit-and-vegetable producer booked a large gain related to its recent divestiture of several business lines and an increase in revenue, though earnings from continuing operations weakened.

Dresser-Rand Group Inc.'s (DRC) second-quarter earnings rose 57% as the equipment maker continued to record strong growth in aftermarket bookings.

Edwards Lifesciences Corp.'s (EW) second-quarter earnings rose 39% as its key replacement heart valve showed sales gains in the U.S. and Europe.

Flextronics International Ltd.'s (FLEX) fiscal first-quarter earnings dropped 54% after the contract electronics manufacturer posted about $41 million in restructuring charges, though results beat the company's guidance.

Freescale Semiconductor Ltd.'s (FSL) second-quarter loss widened as the chip maker was hurt by debt-extinguishment and refinancing charges, masking a modest sales increase as most of the company's main product groups reported growth.

Global Payments Inc.'s (GPN) fiscal fourth-quarter earnings surged as the credit-card processor recorded fewer costs related to a security breach last year and its revenue grew.

HealthSouth Corp.'s (HLS) second-quarter results beat expectations as profits more than tripled thanks to a big income-tax benefit as well as revenue growth.

KBR Inc.'s (KBR) second-quarter earnings fell 13% as the defense contractor posted decreased revenue in its hydrocarbons and government segments. Still, results beat analyst expectations.

LogMeIn Inc. (LOGM) swung to a second-quarter loss as the information-technology company's costs outpaced revenue growth. However, results beat expectations.

McKesson Corp.'s (MCK) fiscal first-quarter earnings rose 12% as the medical-products distributor posted broad revenue growth and a boost from a recent acquisition.

Principal Financial Group Inc.'s (PFG) second-quarter profit rose 33% as the asset manager and insurer continued to benefit from its global growth. Results exceeded Wall Street expectations.

Republic Services Inc.'s (RSG) second-quarter earnings declined 62% as an environmental remediation charge and pension-related costs hurt the waste-collection and recycling-services company's bottom-line results.

Taubman Centers Inc.'s (TCO) second-quarter earnings rose 6.9% and a key profit measure improved as the luxury-mall owner pulled in higher rents.

Universal Health Services Inc.'s (UHS) second-quarter profit jumped 41% as revenue for the health-care facility operator's acute-care and behavioral segments rose, and as the bottom line was lifted by a nearly $38 million gain.

VeriSign Inc.'s (VRSN) second-quarter profit jumped 23% as the Internet-domain-name company reported a double-digit increase in revenue and higher operating margins, lifting results above Wall Street's expectations.

Western Refining Inc. (WNR) has filed plans for an initial public offering for some of its pipeline, transportation and storage assets, a move that comes months after the company began to mull the formation of a limited partnership.

XL Group PLC (XL) and Stone Point Capital LLC formed a new company that will manage investments in insurance-linked securities and other products in reinsurance capital markets.

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

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