Microsoft just became a Foursquare investor and the startup’s biggest source of revenue, as noted by The Wall Street Journal. The two companies have reached a licensing agreement that will see Foursquare’s valuable data used in products like Windows Phone and Bing.

As part of the deal, Microsoft is adding a $15 million investment to Foursquare’s $35 million Series D round from last December. According to the Journal, Foursquare was valued at $650 million when the round took place.

Foursquare CEO Dennis Crowley told Fast Company that the licensing agreement goes deeper than a standard API integration and will offer access to features like real-time recommendations that aren’t yet part of the API. Microsoft, however, won’t have an exclusive on the data.

In a blog post announcing the new partnership, Foursquare wrote:

So, in the near future, when you use Microsoft devices powered by the Windows and Windows Phone operating systems and products like Bing, places will be enhanced by Foursquare – to provide contextually-aware experiences and the best recommendations of any service in the world

Foursquare Teams With Microsoft for Dollars and Data

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