According to an Instagram blog post:
“We may share User Content and your information (including but not limited to, information from cookies, log files, device identifiers, location data, and usage data) with businesses that are legally part of the same group of companies that Instagram is part of, or that become part of that group (“Affiliates”). Affiliates may use this information to help provide, understand, and improve the Service (including by providing analytics) and Affiliates’ own services (including by providing you with better and more relevant experiences). But these Affiliates will honor the choices you make about who can see your photos.”
This update comes shortly after Facebook’s Site Governance vote ended and changes proposed from that vote prepare to go into affect. One change from the site governance vote was allowing Facebook to share data to and from its affiliates such as Instagram.
With the Site Governance vote out of the way both social networks are moving forward to further deepen their integration with one another. Instagram users may soon see the ability to log in with Facebook and to gain access to Facebook data.
When the day comes to monetize Facebook will have a gold mine of information to better target ads.