YAMMER:

The Deal: $1.2 billion

Microsoft really struck gold by acquiring social site Yammer for $1.2 billion in June 2012. According to Microsoft, the acquisition saw a new trend across the business software arena, as Yammer is now often called the Facebook of workplace. The interesting part of Yammer is the services are designed in such a way that they are so appealing to the employees. Overall, a successful investment for Microsoft.

SKYPE:

The Deal: $8.5 billion

Another success story from Microsoft, Skype was acquired in May 2011. Microsoft marked the deal for $8.5 billion which was considered to be one of the biggest acquisitions at that time. Today, the online video chatting company is considered to be one of the best service providers among enterprise space.

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