diff --git a/specification/resources/resource-manager/Microsoft.Resources/stable/2019-10-01/resources.json b/specification/resources/resource-manager/Microsoft.Resources/stable/2019-10-01/resources.json
index 38d40fc7b844..90f76d3cbe11 100644
--- a/specification/resources/resource-manager/Microsoft.Resources/stable/2019-10-01/resources.json
+++ b/specification/resources/resource-manager/Microsoft.Resources/stable/2019-10-01/resources.json
@@ -257,6 +257,7 @@
           "Deployments"
         ],
         "operationId": "Deployments_ValidateAtScope",
+        "x-ms-long-running-operation": true,
         "description": "Validates whether the specified template is syntactically correct and will be accepted by Azure Resource Manager..",
         "parameters": [
           {
@@ -285,6 +286,9 @@
               "$ref": "#/definitions/DeploymentValidateResult"
             }
           },
+          "202": {
+            "description": "Accepted - The request has been accepted for processing and the operation will complete asynchronously."
+          },
           "400": {
             "description": "Returns the validation result.",
             "schema": {
@@ -561,6 +565,7 @@
           "Deployments"
         ],
         "operationId": "Deployments_ValidateAtTenantScope",
+        "x-ms-long-running-operation": true,
         "description": "Validates whether the specified template is syntactically correct and will be accepted by Azure Resource Manager..",
         "parameters": [
           {
@@ -586,6 +591,9 @@
               "$ref": "#/definitions/DeploymentValidateResult"
             }
           },
+          "202": {
+            "description": "Accepted - The request has been accepted for processing and the operation will complete asynchronously."
+          },
           "400": {
             "description": "Returns the validation result.",
             "schema": {
@@ -871,6 +879,7 @@
           "Deployments"
         ],
         "operationId": "Deployments_ValidateAtManagementGroupScope",
+        "x-ms-long-running-operation": true,
         "description": "Validates whether the specified template is syntactically correct and will be accepted by Azure Resource Manager..",
         "parameters": [
           {
@@ -899,6 +908,9 @@
               "$ref": "#/definitions/DeploymentValidateResult"
             }
           },
+          "202": {
+            "description": "Accepted - The request has been accepted for processing and the operation will complete asynchronously."
+          },
           "400": {
             "description": "Returns the validation result.",
             "schema": {
@@ -1185,6 +1197,7 @@
           "Deployments"
         ],
         "operationId": "Deployments_ValidateAtSubscriptionScope",
+        "x-ms-long-running-operation": true,
         "description": "Validates whether the specified template is syntactically correct and will be accepted by Azure Resource Manager..",
         "parameters": [
           {
@@ -1213,6 +1226,9 @@
               "$ref": "#/definitions/DeploymentValidateResult"
             }
           },
+          "202": {
+            "description": "Accepted - The request has been accepted for processing and the operation will complete asynchronously."
+          },
           "400": {
             "description": "Returns the validation result.",
             "schema": {
@@ -1622,6 +1638,7 @@
           "Deployments"
         ],
         "operationId": "Deployments_Validate",
+        "x-ms-long-running-operation": true,
         "description": "Validates whether the specified template is syntactically correct and will be accepted by Azure Resource Manager..",
         "parameters": [
           {
@@ -1660,6 +1677,9 @@
               "$ref": "#/definitions/DeploymentValidateResult"
             }
           },
+          "202": {
+            "description": "Accepted - The request has been accepted for processing and the operation will complete asynchronously."
+          },
           "400": {
             "description": "Returns the validation result.",
             "schema": {