1920-40 marks a period of very high quality pocket knives and ingenuity for the Case brand.  Many of the patterns that would thrive into the next 50 years would come from this most important era in the company’s history.  The “Tested XX” trademark was officially registered in 1905 by Jean Case of the Case Brothers Cutlery Co of Springille, N.Y.  In 1914, Jean sold the rights of the Tested XX trademark to J. Russell Case of W.R. Case & Sons Cutlery Co for the sum of $1500.

Case Tested XX Pocket Knives
1920-40 Case Tested XX pocket knives

The stamp from the 1920-40 era features a large circle C that extends underneath the “ASE” in Case.  Underneath this were the words, “Tested XX.”  The shields on the handles from the Tested era feature a “closed” C in the word Case.  After 1940, most of the shields had an “open” C.

The bone and stag handles from this era are remarkably striking as well.  These Case Tested XX pocket knives are scarce and highly sought after by collectors today including the large cigar, large stockman and large congress knife.  Check out my Case knives page and Remington knives page as well.

I appreciate any traffic from these links as I earn commission when an item is purchased, at no extra cost to you. THANK YOU!!!   – Jesse, oldpocketknives.com

Vintage Case Tested Xx greenbone 1920-1940 knife Very Nice 6210 1/2 teardrop
eBay
$695.00
Vintage Case Tested Xx greenbone 1920-1940 knife Very Nice 6210 1/2 teardrop
1920-40 CASE TESTED XX (#2231) SLICK BLACK "TORPEDO JACK" POCKET KNIFE- MINTY
eBay
$399.99
1920-40 CASE TESTED XX (#2231) SLICK BLACK "TORPEDO JACK" POCKET KNIFE- MINTY
Vintage CASE TESTED XX 1920-1940 3 Blade Pocket Knife
eBay
$72.00
Vintage CASE TESTED XX 1920-1940 3 Blade Pocket Knife
VINTAGE CASE TESTED XX 2217 2 BLADE SLICK BLACK HANDLES 1920-1940 KNIFE
eBay
$300.00
VINTAGE CASE TESTED XX 2217 2 BLADE SLICK BLACK HANDLES 1920-1940 KNIFE
VINTAGE CASE XX TESTED USA knife 1920-1940 CHRISTMAS TREE TADPOLE RARE ITEM
eBay
$300.00
VINTAGE CASE XX TESTED USA knife 1920-1940 CHRISTMAS TREE TADPOLE RARE ITEM
Vintage Case Tested greenbone 1920-40 jack knife Very Nice 6231 1/2
eBay
$699.99
Vintage Case Tested greenbone 1920-40 jack knife Very Nice 6231 1/2
-15%
vintage CASE TESTED 1920-1940 knife 6220 Green Bone PEANUT KNIFE excellent
eBay
$420.75 $495.00
vintage CASE TESTED 1920-1940 knife 6220 Green Bone PEANUT KNIFE excellent
-15%
vintage Case Tested 1920-1940 knife Rough Black Cigar Knife very Nice 6345 1/2
eBay
$505.75 $595.00
vintage Case Tested 1920-1940 knife Rough Black Cigar Knife very Nice 6345 1/2
-15%
Vintage Case Tested knife 1920-1940s very nice
eBay
$403.75 $475.00
Vintage Case Tested knife 1920-1940s very nice
VINTAGE CASE TESTED XX 1920-1940 BONE HANDLE SINGLE BLADE KNIFE
eBay
$199.95
VINTAGE CASE TESTED XX 1920-1940 BONE HANDLE SINGLE BLADE KNIFE
-14%
Case Tested XX Slick Black 2 Blade Regular Pocket Jack Knife Vintage 1920s - 40s
eBay
$165.71 $194.95
Case Tested XX Slick Black 2 Blade Regular Pocket Jack Knife Vintage 1920s - 40s