diff --git a/core/library.json b/core/library.json
index 3f7cc40..d3ed6df 100644
--- a/core/library.json
+++ b/core/library.json
@@ -34,22 +34,6 @@
           "items": {
             "type": "string",
             "description": "Globally unique identifier referring to the actual signature"
-          },
-          "Signature_keys": {
-            "type": "array",
-            "description": "The signature fields of this library.",
-            "items": {
-              "type": "string",
-              "description": "Name of the field"
-            }
-          }
-        },
-        "Signature_keys": {
-          "type": "array",
-          "description": "List of keys available in the signature's metadata",
-          "items": {
-            "type": "string",
-            "description": "Key identifier"
           }
         }
       },
diff --git a/core/library.test.json b/core/library.test.json
index da2606a..2181ea9 100644
--- a/core/library.test.json
+++ b/core/library.test.json
@@ -30,10 +30,6 @@
         "dataset_type": "geneset_library",
         "signatures": [
           "1"
-        ],
-        "Signature_keys": [
-          "Genes",
-          "Cell_Line"
         ]
       }
     },