Remove hidden information help??

[franken1]

So I need to fix approximately 150 pdf files that have employee names in them.  All in the hidden information.  When I use the tool "remove hidden information", for some reason its marking spaces between words as "hidden".  The only thing in that example picture I've attached is the blacked out wording.  None of those squares should be removed.  Unfortunately, because its marking these, the resulting file is "choppy" and can't be read easily.  Any ideas on why its doing this?  Or how to fix it?   If I have to remove all the names manually, its going to take a long long time. 

Also, any idea what that square character is called?