Among others i am also a Schrade collector. If you hang out in the Schrade Knife Collectors forum here (very bottom of "Manufacturers Forums"), every minute change in every production knife is noted and talked about. e.g. change of length of a swedge on the 8OT clip blade, or change from matchstriker to regular pull, etc., on & on. No detail is ever overlooked.
With the closure of Schrade in 2004 some forum members purchased all the tons of paperwork, contains minutes of business meetings, shop floor production notes for every day, etc. These notes give definite evidence of when certain runs were made and who they were making it for (lots of SFO's), etc.
You can get as deep into the history of any knife or any knife company as you feel driven to. Soon you find out that what is marked on a knife as far as name, etc. often means very little, as all knife companies were making knives or knife parts for each other so it becomes a forensic puzzle to figure out who made what.
And all of this is a lot of fun.
kj