Microsoft has reportedly struck a deal to purchase Yammer for $1bn.
Microsoft sets mystery press briefing for Monday
The technology giant could complete the acquisition of the business social network firm in the next few days, according to reports. Yammer would mean Microsoft could add social networking tools to its office software suite.
Microsoft has also scheduled a press event for Monday 18 June at a secret location in Los Angeles. It's possible that the firm will use the event for this very announcement.
Last year Microsoft purchased internet video and voice leader Skype for $8.5bn. Yammer is known as the Facebook for businesses and is used by more than 200,000 companies worldwide. Neither firm has commented on the issue.
It is also possible that Microsoft will include Yammer into its upcoming Windows 8 operating system which is designed for tablets as well as desktop PCs and laptops.