CA – The software company is the target of a lawsuit by the Justice Department for allegedly overcharging the government for software and services.

Apple –A Nomura Securities research report predicts Apple will unveil details about its " wearables " platform at its upcoming World Wide Developer Conference, including the so-called " iWatch ."

Big Lots – The discount retailer reported first quarter profit of 50 cents per share, excluding certain items, six cents above estimates. Big Lots also raised its forecast for the full year as its sales increase.

Check out which companies are making headlines before the bell:

Express–The retailer posted first quarter profit of six cents per share, eight cents below estimates. Sales fell short of forecasts as well, as does the company's current quarter earnings forecast. The company said its spring inventory sold slowly, and the specialty apparel chain's Memorial Day promotion did not drive traffic as successfully as last year.

Pacific Sunwear–The teen apparel retailer reported a first quarter loss of 11 cents per share, two cents smaller than anticipated. However, the company gave lower than expected revenue and earnings guidance for the current quarter, due in part to increased promotions and underperformance in several women's categories.

Lions Gate Entertainment–The studio's revenue fell short of expectations for the latest quarter, and was down 8.1 percent from a year ago despite continued box office success for its films.

Splunk–Splunk lost four cents per share for the first quarter, two cents smaller than estimates. Revenue beat consensus, as the maker of data analysis software was able to expand its customer base. Splunk also raised its revenue estimate for the full year.

Salesforce.com–The customer relations software company entered a strategic partnership with Microsoft, which puts Salesforce software on Windows devices and lets it operate in conjunction with Microsoft's popular Office software suite.

Annie's–Annie's fell five cents short of estimates with profit of 29 cents per share for the fourth quarter. Revenue was slightly short of estimates as well, and the natural foods company gave a full-year earnings projection that's well short of estimates. The company pointed to higher input costs, among other factors.

Twitter–The microblogging site's senior vice president of engineering Christopher Fry has resigned from that position, although he will remain in an advisory role. The resignation was revealed in an SEC filing, which did not give a specific reason.

Diageo–The company is building a new bourbon distillery in Shelby County, Kentucky, hoping to have the $115 million facility operating by late 2016.

Oracle–The technology giant may be sued over Oregon's failed health care website. Gov. John Kitzhaber has asked the state attorney general to take legal action against Oracle, which built the state's health insurance enrollment system. The $134 million site experienced multiple issues and the state eventually switched to the federal portal, healthcare.gov.

—By CNBC's Peter Schacknow

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