7.-- FireEye  (FEYE) shares rose 24% to $51 in after-hours trading on Thursday after announcing it will acquire computer forensics company Mandiant for $1.05 billion in cash and stock, reported preliminary fourth-quarter results, and raised 2014 revenue guidance based on the acquisition. 

Mandiant is best known for revealing a Chinese military unit that was reportedly behind several hacking attacks on U.S. companies. 

8.-- Snapchat said Thursday it plans to issue a more secure version of its application after online usernames and partial phone numbers of 4.6 million users of Snapchat were posted online. 

Snapchat said in a blog post lthat the updated version of its app would allow users to opt out of its "Find Friends" feature, which was apparently at the heart of the security breach. 

9.-- BlackBerry  (BBRY) will part ways with musician Alicia Keys at the end of January, the smartphone maker announced on Thursday.

BlackBerry hired Keys as its global creative director in the early part of 2013, announcing her position at the launch event for BlackBerry 10. 

In a statement the company said, "BlackBerry and Alicia Keys have completed our yearlong collaboration."

10.-- Facebook (FB) is facing a class-action lawsuit over claims the social networking giant monitors users' private messages to sell the data to advertisers, The Financial Times reported.

The plaintiffs alleged Facebook systematically intercepts private messages to obtain data it shares with marketers, giving the company an advantage over other data aggregators, the FT reported.

Facebook said it believes "the allegations are without merit and we will defend ourselves vigorously."

-- Written by Joseph Woelfel