MS Office XML rsid information leaks metadata about how a particular document was edited
Microsoft's documentation (linked above) describes the rsidrpr as:
a unique identifier used to track the editing session when the physical character representing this section mark was last formatted.
see also Brian Jones' blog about RSIDs: https://blogs.msdn.microsoft.com/brian_jones/2006/12/11/whats-up-with-all-those-rsids/.
It appears that these "revision session IDs" are contained in
word/document.xml as attributes of the form
This leaks information about how the document was created, and which things came from which authors. These references should probably be stripped.