diff --git a/specification/synapse/resource-manager/Microsoft.Synapse/preview/2019-06-01-preview/bigDataPool.json b/specification/synapse/resource-manager/Microsoft.Synapse/preview/2019-06-01-preview/bigDataPool.json
index d34af3709d92..2d9cc2b82014 100644
--- a/specification/synapse/resource-manager/Microsoft.Synapse/preview/2019-06-01-preview/bigDataPool.json
+++ b/specification/synapse/resource-manager/Microsoft.Synapse/preview/2019-06-01-preview/bigDataPool.json
@@ -442,6 +442,13 @@
           "$ref": "#/definitions/LibraryRequirements",
           "description": "Library version requirements"
         },
+        "customLibraries": {
+          "description": "List of custom libraries/packages associated with the spark pool.",
+          "type": "array",
+          "items": {
+            "$ref": "../../../../data-plane/Microsoft.Synapse/preview/2019-06-01-preview/library.json#/definitions/LibraryResourceProperties"
+          }
+        },
         "sparkConfigProperties": {
           "$ref": "#/definitions/LibraryRequirements",
           "description": "Spark configuration file to specify additional properties"