diff --git a/specification/apimanagement/resource-manager/Microsoft.ApiManagement/preview/2018-01-01/apimdeployment.json b/specification/apimanagement/resource-manager/Microsoft.ApiManagement/preview/2018-01-01/apimdeployment.json
index 11a7554f887b..53d09bf7db69 100644
--- a/specification/apimanagement/resource-manager/Microsoft.ApiManagement/preview/2018-01-01/apimdeployment.json
+++ b/specification/apimanagement/resource-manager/Microsoft.ApiManagement/preview/2018-01-01/apimdeployment.json
@@ -689,8 +689,7 @@
         },
         "certificate": {
           "$ref": "#/definitions/CertificateInformation",
-          "description": "Certificate information.",
-          "readOnly": true
+          "description": "Certificate information."
         }
       },
       "required": [
diff --git a/specification/apimanagement/resource-manager/Microsoft.ApiManagement/preview/2018-06-01-preview/apimdeployment.json b/specification/apimanagement/resource-manager/Microsoft.ApiManagement/preview/2018-06-01-preview/apimdeployment.json
index 9ffca9a104d3..2c5e974dc936 100644
--- a/specification/apimanagement/resource-manager/Microsoft.ApiManagement/preview/2018-06-01-preview/apimdeployment.json
+++ b/specification/apimanagement/resource-manager/Microsoft.ApiManagement/preview/2018-06-01-preview/apimdeployment.json
@@ -689,8 +689,7 @@
         },
         "certificate": {
           "$ref": "#/definitions/CertificateInformation",
-          "description": "Certificate information.",
-          "readOnly": true
+          "description": "Certificate information."
         }
       },
       "required": [