There are an estimate 200 KA-BAR tang stamps used since 1898. However, only a fraction of those are known today and even fewer used on a regular basis. Some of the more prominent tang stamps are listed below.
Prominent KA-BAR Tang Stamps Since 1898
KA-BAR, Olean N.Y.
Ka-bar, Olean N.Y.
Kabar (Pattern Number Underneath), USA
Union Cutlery Co., Tidioute, Pa
Union Cut.Co., Tidioute
Union Cut. Co., Olean N.Y. (First Use in 1909)
Union (letters inside North American Shield)
U-R Co., Tidioute PA
Union Razor Co., Tidioute, Pa
VikingU-C Co. Olean, N.Y. USA
Below is a photo of tang stamps taken directly from knives