Well, in truth A.G. is right. Buck did not invent the lock back folding hunter any more than Al Mar invented the mid lock folder. Buck did make it very popular though and they did modify it slightly by using a piano wire for a spring which hadn't been done before.
Both of these types of locks are hundreds of years old though. Puma was making that Deer Hunter for many many years before Buck even concieved of a folder. I would have to do some research but I believe the Deer Hunter by Puma predates Buck as a company.
Bernard Levine would probably know for sure. But if I can find the write up in one of my books I'll post it.
EDIT:
I have this reply from Bernard via email.
I'll add before that that the Buck company started in 1902 in Kansas I believe. Puma was started in 1769. Somewhere in my stuff I have a paper that said Puma made their first locking folder in 1860 something. But I have not had any luck finding that.
Here is Bernard Levine's comment on this also.
"Various sorts of knife locks were already common in the 18th century. The oldest type of
lock is the Barry Wood swing lock type, which was made in the 17th century, and possibly
earlier -- it does not need springs. Versions of this mechanism were patented by 10
different Americans and 10 different Brits, some of whom simply traced 18th century
drawings for their 19th century patent applications.
The Buck 110 was introduced in 1963. It uses a rocker bar and music wire spring, which is
completely different internally from a traditional lockback (which uses a two-part
backspring), despite looking the same externally. Shown in Levine's Guide to Knives. Buck
used it because it is simpler to make, but it is also stronger and more reliable. I don't
know if Buck invented this, but they did not attempt to patent it, so practically everyone
has copied it since then."
