Among the companies with shares expected to actively trade in Wednesday's session are MasterCard Inc. (MA), Air Products and Chemicals Inc. (APD) and Riverbed Technology Inc. (RVBD).

MasterCard, the world's second-largest payments network, reported a 21.1% increase in second-quarter profit as spending on its credit and debit cards rose 11.7%. Shares rose 3.4% to $622.00 premarket as results beat the estimates of analysts.

Activist investor William Ackman bought a 9.8% stake in Air Products and Chemicals for $2.2 billion, his firm's largest investment to date, according to a report in The Wall Street Journal that cites people familiar with the matter. Shares of the supplier of hydrogen and semiconductor materials rose 4.1% to $109.94 premarket.

Riverbed Technology swung to a second-quarter loss as expenses increased, masking revenue growth driven in part by business it has gained from its Opnet Technologies Inc. acquisition. Shares were down 16% at $14.80 premarket as revenue fell short of the company's expectations.

Oil States International Inc.'s (OIS) board has approved a plan to spin off its accommodations business, a move that will separate the company's business that provides technology and services to the deepwater and shale play markets from its remote site accommodations segment. The energy company's shares jumped 7.8% to $104.49 premarket.

Cubist Pharmaceuticals Inc. (CBST) unveiled a pair of deals to acquire two smaller biopharmaceutical peers, transactions that could total a combined $1.6 billion if certain sales milestones are achieved. Separately, Cubist said it was paying about $535 million to acquire Optimer Pharmaceuticals Inc. (OPTR) and $707 million to buy Trius Therapeutics Inc. (TSRX). The news sent Cubist's shares up 5.3% to $60.00 in premarket trading. Trius's shares jumped 18% to $13.80 in premarket trading, while Optimer's slid 6% to $12.49.

SodaStream International Ltd. (SODA) reported a good-looking second-quarter beat, especially on the bottom line, allowing the company to again boost 2013 expectations and give life to a stock that's sold off strongly this month amid growth and competitive concerns. Shares of the maker of in-home soda machines rose 7.6% to $62.73 premarket.

Restaurant operator Ignite Restaurant Group Inc. (IRG) preannounced second-quarter results that missed analysts' expectations. The company said results were "significantly impacted" by the company's decision to increase spending in its Macaroni Grill business to try to drive "immediate sales improvement." Shares fell 12% to $16.10 premarket.

BioCryst Pharmaceuticals Inc. (BCRX) is offering to sell shares, but didn't say how many. The company is seeking to fund clinical development of drugs including BCX4161, a potential treatment for hereditary angioedema, an immune system disorder. Shares were off 5.5% premarket to $3.76.

Enterprise networking software vendor Jive Software Inc. (JIVE) reported second-quarter revenue in-line with analysts' expectations and beat on the bottom line. However, shares fell 18% to $14.01 premarket trading as the company forecast current quarter and full-year results below expectations.

Questcor Pharmaceuticals Inc.'s (QCOR) second-quarter profit grew 67% on increased adoption of its primary drug, Acthar. Shares jumped 17% to $60.69 premarket as top- and bottom-line results easily beat analyst expectations.

Scorpio Tankers Inc. (STNG) plans to offer 20 million shares to raise funds for acquiring more fuel-efficient tanker vessels in an effort to gain an edge in a competitive market. The oil-tanker company recently had around 164.7 million shares outstanding. Shares fell 5.8% premarket to $9.64.

Symantec Corp.'s (SYMC) fiscal first-quarter profit slipped 1.9% as the security-software maker logged higher operating expenses, masking slight revenue growth. Shares rose 4.8% to $25.52 premarket as results topped the company's expectations.

BRE Properties Inc.'s (BRE) second-quarter profit rose 52% as the real-estate investment trust's funds from operations performance beat expectations. Shares rose 11% to $57.50 premarket.

 
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Aflac Inc.'s (AFL) second-quarter earnings rose 84% on the strength of after-tax investment gains.

Amgen Inc. (AMGN) said its second-quarter earnings edged lower on increased research and development costs, as executives sought to assure investors that the company would be judicious in any acquisition discussions.

Arthur J. Gallagher & Co.'s (AJG) second-quarter profit rose 30% as the insurance broker and consulting firm continued to book strong growth in commissions and fees.

Shares of Big 5 Sporting Goods Corp. (BGFV) slid in after-hours trading Tuesday after the retailer reported second-quarter sales that fell short of expectations, as well as a muted outlook for the current quarter. Investors ignored a second-quarter profit that doubled from last year's level due to higher sales and expanding margins.

Boston Properties Inc.'s (BXP) second-quarter profit soared from a year earlier as a gain related to the consolidation of the office landlord's joint ventures boosted results, though a key metric known as funds from operations fell slightly.

Chicago Bridge & Iron Co.'s (CBI) second-quarter earnings increased 47% the engineering and construction company's revenue more than doubled.

Covance Inc. (CVD) swung to a second-quarter profit after the drug-research outsourcing company's results a year ago were weakened by write-downs and revenue in the late-stage development business grew in the latest period.

Equity Residential's (EQR) second-quarter income surged as the apartment landlord recorded a hefty gain from the sale of properties.

Fiserv Inc.'s (FISV) second-quarter earnings fell 6.2% as the financial-technology provider's expenses--including costs to integrate its Open Solutions Inc. acquisition--masked higher revenue.

Genworth Financial Inc.'s (GNW) second-quarter earnings surged 85% as the life insurer's U.S. mortgage-insurance business remained profitable for the second quarter in a row, and expenses declined. Results fell short of analyst expectations.

Hanesbrands Inc.'s (HBI) second-quarter earnings soared, topping analysts' estimates, as the apparel maker recorded higher sales and lower costs, boosting margins.

IAC/InterActiveCorp.'s (IACI) second-quarter profit grew 35% as the Internet company reported higher sales due to the contribution of About Group, as well as an increase in revenue from Match.com.

Jones Lang LaSalle Inc.'s (JLL) second-quarter profit grew 24%, as higher fee revenue helped bolster the top line, though overall quarterly results missed Wall Street's expectations.

Kimco Realty Corp.'s (KIM) second-quarter profit fell 26% as the mall landlord was hurt by property writedowns, though its core funds from operations improved.

Nanometrics Inc. (NANO) swung to a second-quarter loss as the chip equipment maker posted a double-digit revenue decline and weaker margins. The company provided downbeat current-quarter guidance.

NCR Corp. (NCR) second-quarter profit fell 16% as the maker of automatic teller machines saw higher expenses and the prior-year period had income from discontinued operations, masking a jump in sales and wider margins.

Oneok Inc.'s (OKE) second-quarter earnings plunged on a $71 million after-tax charge related to its energy-services business that masked better-than-expected revenue growth. Pipeline and natural-gas gathering business Oneok Partners LP (OKS) reported that its second-quarter profit increased 2% amid narrower natural-gas-liquids price spreads and continued ethane-rejection related impacts.

Qiagen NV (QGEN) swung to surprise second-quarter loss on a restructuring charge of $76 million and other items that overwhelmed the medical-testing technologies company's revenue growth.

RenaissanceRe Holdings Ltd.'s (RNR) second-quarter earnings declined 77% as the insurer logged an increase in net claims and claim expenses as a result of floods in Europe and tornadoes in the U.S., though operating profit improved.

Take-Two Interactive Software Inc. (TTWO) reported a narrower loss in the first quarter on lower revenue, as the videogame maker relied on older products while preparing to release its next "Grand Theft Auto" title.

Fitch Ratings has lifted its outlook on Texas Instruments Inc. (TXN) to stable, saying the chip maker's renewed profitability expansion and pockets of revenue growth should enable it to protect the company's current rating.

UGI Corp. (UGI) swung to a gain in its fiscal third-quarter, due to stronger performance in the gas distributor's international unit and its AmeriGas Partners LP (APU) operations, which said it narrowed its loss from the year-ago period.

Weatherford International Ltd.'s (WFT) second-quarter loss narrowed as the oilfield-services company recorded fewer charges, and revenue outside of North America grew.

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

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