FireEye’s shares rose by more than 30 percent on Friday following the network security firm’s purchase of Mandiant

Although the $1 billion deal closed Monday, it wasn’t until Thursday that it was officially announced via a press release on Mandiant’s website. FireEye will pay $106.5 million in net cash to Mandiant stakeholders, as well as issue 21.5 million shares and options in the deal, worth about $900 million.

By Friday afternoon, FireEye’s shares were trading at more than $55. Its shares have more than doubled since debuting in September. Additionally, the company raised its fourth-quarter revenue forecast on Thursday.