The 3rd Gen frame will only have "Glock, Inc. Smyrna, GA" WITHOUT "Made In Austria" below it.
Keep in mind that Glock used this sort of mark in the late 80's through the very early 90's.
USMCR 1997 - 2004
PAARNG 2011 - Present
Founder - Glock Collectors Club PA Glocker #39
Looking for G22 PE389US
Multiple Armorer Certifications