Q:

Document sharing history, who shared this document with whom and when?

Is there a way to see when exactly a document was "shared" with someone else?
For example, John doesn't have access to see Document A. So Matt, who has access to the document, clicks "Share" on the document in the doc library, and invites John to view Document A. Several weeks later the document owner needs to know who shared the document with John, and when.
So, something similar to Version History, except it would show "Sharing History" or "Permissions History" or some-such.
For this scenario, we are using SharePoint 2013 On-Premise. I do have direct access to the DB if that matters.

A:

You are looking for auditing. 

You can use the audit feature of Microsoft SharePoint Server 2013 to track which users have taken what actions on the sites, content types, lists, libraries, list items, and library files of site collections. Knowing who has done what with which information is critical for many business requirements, such as regulatory compliance and records management.

Configure audit settings for a site collection

