What is the use of the is_data_sharing field in eav_entity_type?

I may be wrong, but I think for now it does nothing.
Maybe it's the start of a feature that didn't get implemented yet.
I've searched in the code for anything matching is_data_sharing, isDataSharing and the only places where they show up are

• is_data_sharing in the install/upgrade files from the eav module
• isDataSharing just in the annotations (getter and setter) in the Entity type model in the eav module.

I have search for is_data_sharing column used in magento structure but not find any use of it.

so may be this field used in older version of magento but it's no longer used in magento 1.9 and higher

I am not sure about this but is_data_sharing term is mostly used for privileges. In DB it maybe related to privileges of attributes Or it maybe use for share attributes between magento stores.