Information
This recommendation pertains to AirDrop in the context of Apple's managed app implementation.
The terms 'managed' and 'unmanaged' refer to app classifications made through Managed Open In, a feature introduced in iOS 7. Managed Open In provides for data containerization. Institutionally provisioned apps are designated managed. Apps elected by the end user are designated unmanaged.
Rationale:
When AirDrop is allowed as a managed destination, sensitive data may be moved out of the managed app space to an unmanaged device.
Solution
Open Apple Configurator.
Open the Configuration Profile.
In the left windowpane, click on the Restrictions tab.
In the right windowpane, under the tab Functionality, check the checkbox for Treat AirDrop as unmanaged destination.
Deploy the Configuration Profile.
Additional Information:
Note that the feature specifically mentions destination and not source. Following this recommendation does not prevent AirDrop connections into the managed app space, only AirDrop connections out of the managed app space.