Foster - I don't know where you work, but in most American work places your work product belongs to the employer whether it is a report, a note, a muffin or a Ford F150.  In Director Comey's case, he wrote an official note about his meeting with President Trump.  The note belongs to the government and is not Comey's private property to do with what he pleases.  The sensitive nature of the note makes it privileged and discoverable.