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 XX TESTED USA knife 1920-1940 CHRISTMAS TREE TADPOLE RARE ITEM
eBay
$295.00
VINTAGE CASE XX TESTED USA knife 1920-1940 CHRISTMAS TREE TADPOLE RARE ITEM
CASE TESTED XX GREENBONE Single Blade KNIFE 1920-1940
eBay
$61.00
CASE TESTED XX GREENBONE Single Blade KNIFE 1920-1940
1920-1940 Case Tested Fishing Knife Rare
eBay
$350.00
1920-1940 Case Tested Fishing Knife Rare
Case- Tested XX- 1920-1940- 6235 EO- Pocket Knife
eBay
$900.00
Case- Tested XX- 1920-1940- 6235 EO- Pocket Knife
VINTAGE CASE TESTED XX 1920-1940 3 Blade Jigged Bone Pocket Knife
eBay
$155.50
VINTAGE CASE TESTED XX 1920-1940 3 Blade Jigged Bone Pocket Knife
-15%
vintage Case Tested 1920-1940 knife Rough Black Cigar Knife very Nice
eBay
$505.75 $595.00
vintage Case Tested 1920-1940 knife Rough Black Cigar Knife very Nice
-15%
vintage Case Tested Knife 1920-1940 slick Black Excellent Condition 2231 sab
eBay
$335.75 $395.00
vintage Case Tested Knife 1920-1940 slick Black Excellent Condition 2231 sab
1920s/40s Vintage Case Tested XX Split Back Folding Pocket Knife (3380)
eBay
$150.00
1920s/40s Vintage Case Tested XX Split Back Folding Pocket Knife (3380)
-15%
vintage Case Tested Knife 1920-1940 Rough Black Handles nice stockman 6347
eBay
$501.50 $590.00
vintage Case Tested Knife 1920-1940 Rough Black Handles nice stockman 6347
-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
Vintage Case Tested XX Texas Toothpick 1920-1940 Rare Gold for Restoration
eBay
$199.99
Vintage Case Tested XX Texas Toothpick 1920-1940 Rare Gold for Restoration