diff --git a/specification/keyvault/resource-manager/Microsoft.KeyVault/stable/2019-09-01/examples/createVault.json b/specification/keyvault/resource-manager/Microsoft.KeyVault/stable/2019-09-01/examples/createVault.json
index c6e78d6d9d53..233ffdfc299c 100644
--- a/specification/keyvault/resource-manager/Microsoft.KeyVault/stable/2019-09-01/examples/createVault.json
+++ b/specification/keyvault/resource-manager/Microsoft.KeyVault/stable/2019-09-01/examples/createVault.json
@@ -170,6 +170,7 @@
           "enabledForDeployment": true,
           "enabledForDiskEncryption": true,
           "enabledForTemplateDeployment": true,
+          "hsmPoolResourceId": "00000000-0000-0000-0000-000000000000",
           "vaultUri": "https://sample-vault.vault.azure.net",
           "provisioningState": "Succeeded"
         }
@@ -243,6 +244,7 @@
           "enabledForDeployment": true,
           "enabledForDiskEncryption": true,
           "enabledForTemplateDeployment": true,
+          "hsmPoolResourceId": "00000000-0000-0000-0000-000000000000",
           "vaultUri": "https://sample-vault.vault.azure.net",
           "provisioningState": "Succeeded"
         }
diff --git a/specification/keyvault/resource-manager/Microsoft.KeyVault/stable/2019-09-01/examples/createVaultWithNetworkAcls.json b/specification/keyvault/resource-manager/Microsoft.KeyVault/stable/2019-09-01/examples/createVaultWithNetworkAcls.json
index f1f359b8a01b..7fd5e68bab06 100644
--- a/specification/keyvault/resource-manager/Microsoft.KeyVault/stable/2019-09-01/examples/createVaultWithNetworkAcls.json
+++ b/specification/keyvault/resource-manager/Microsoft.KeyVault/stable/2019-09-01/examples/createVaultWithNetworkAcls.json
@@ -69,6 +69,7 @@
           "enabledForDeployment": true,
           "enabledForDiskEncryption": true,
           "enabledForTemplateDeployment": true,
+          "hsmPoolResourceId": "00000000-0000-0000-0000-000000000000",
           "vaultUri": "https://sample-vault.vault.azure.net"
         }
       }
@@ -106,6 +107,7 @@
           "enabledForDeployment": true,
           "enabledForDiskEncryption": true,
           "enabledForTemplateDeployment": true,
+          "hsmPoolResourceId": "00000000-0000-0000-0000-000000000000",
           "vaultUri": "https://sample-vault.vault.azure.net"
         }
       }
diff --git a/specification/keyvault/resource-manager/Microsoft.KeyVault/stable/2019-09-01/examples/getVault.json b/specification/keyvault/resource-manager/Microsoft.KeyVault/stable/2019-09-01/examples/getVault.json
index 10de57627103..3f462d5920df 100644
--- a/specification/keyvault/resource-manager/Microsoft.KeyVault/stable/2019-09-01/examples/getVault.json
+++ b/specification/keyvault/resource-manager/Microsoft.KeyVault/stable/2019-09-01/examples/getVault.json
@@ -74,6 +74,7 @@
           "enabledForDeployment": true,
           "enabledForDiskEncryption": true,
           "enabledForTemplateDeployment": true,
+          "hsmPoolResourceId": "00000000-0000-0000-0000-000000000000",
           "vaultUri": "https://sample-vault.vault.azure.net",
           "provisioningState": "Succeeded"
         }
diff --git a/specification/keyvault/resource-manager/Microsoft.KeyVault/stable/2019-09-01/examples/listVaultByResourceGroup.json b/specification/keyvault/resource-manager/Microsoft.KeyVault/stable/2019-09-01/examples/listVaultByResourceGroup.json
index 9268e5e0946b..a2f657388959 100644
--- a/specification/keyvault/resource-manager/Microsoft.KeyVault/stable/2019-09-01/examples/listVaultByResourceGroup.json
+++ b/specification/keyvault/resource-manager/Microsoft.KeyVault/stable/2019-09-01/examples/listVaultByResourceGroup.json
@@ -77,6 +77,7 @@
               "enabledForDiskEncryption": true,
               "enabledForTemplateDeployment": true,
               "enableSoftDelete": true,
+              "hsmPoolResourceId": "00000000-0000-0000-0000-000000000000",
               "vaultUri": "https://sample-vault.vault.azure.net/",
               "provisioningState": "Succeeded"
             }
diff --git a/specification/keyvault/resource-manager/Microsoft.KeyVault/stable/2019-09-01/examples/listVaultBySubscription.json b/specification/keyvault/resource-manager/Microsoft.KeyVault/stable/2019-09-01/examples/listVaultBySubscription.json
index 53febe7b97f3..2d54f6481eb9 100644
--- a/specification/keyvault/resource-manager/Microsoft.KeyVault/stable/2019-09-01/examples/listVaultBySubscription.json
+++ b/specification/keyvault/resource-manager/Microsoft.KeyVault/stable/2019-09-01/examples/listVaultBySubscription.json
@@ -76,6 +76,7 @@
               "enabledForDiskEncryption": true,
               "enabledForTemplateDeployment": true,
               "enableSoftDelete": true,
+              "hsmPoolResourceId": "00000000-0000-0000-0000-000000000000",
               "vaultUri": "https://sample-vault.vault.azure.net/",
               "provisioningState": "Succeeded"
             }
diff --git a/specification/keyvault/resource-manager/Microsoft.KeyVault/stable/2019-09-01/examples/updateVault.json b/specification/keyvault/resource-manager/Microsoft.KeyVault/stable/2019-09-01/examples/updateVault.json
index 5d7b1268c778..aa0ec1f8e3bb 100644
--- a/specification/keyvault/resource-manager/Microsoft.KeyVault/stable/2019-09-01/examples/updateVault.json
+++ b/specification/keyvault/resource-manager/Microsoft.KeyVault/stable/2019-09-01/examples/updateVault.json
@@ -169,6 +169,7 @@
           "enabledForDeployment": true,
           "enabledForDiskEncryption": true,
           "enabledForTemplateDeployment": true,
+          "hsmPoolResourceId": "00000000-0000-0000-0000-000000000000",
           "vaultUri": "https://sample-vault.vault.azure.net",
           "provisioningState": "Succeeded"
         }
@@ -243,6 +244,7 @@
           "enabledForDiskEncryption": true,
           "enabledForTemplateDeployment": true,
           "vaultUri": "https://sample-vault.vault.azure.net",
+          "hsmPoolResourceId": "00000000-0000-0000-0000-000000000000",
           "provisioningState": "Succeeded"
         }
       }
diff --git a/specification/keyvault/resource-manager/Microsoft.KeyVault/stable/2019-09-01/keys.json b/specification/keyvault/resource-manager/Microsoft.KeyVault/stable/2019-09-01/keys.json
index 3f54b0e4e718..ff2670e0d858 100644
--- a/specification/keyvault/resource-manager/Microsoft.KeyVault/stable/2019-09-01/keys.json
+++ b/specification/keyvault/resource-manager/Microsoft.KeyVault/stable/2019-09-01/keys.json
@@ -461,12 +461,14 @@
               "name": "JsonWebKeyOperation",
               "modelAsString": true
             }
-          }
+          },
+          "readOnly": true
         },
         "keySize": {
           "type": "integer",
           "format": "int32",
-          "description": "The key size in bits. For example: 2048, 3072, or 4096 for RSA."
+          "description": "The key size in bits. For example: 2048, 3072, or 4096 for RSA.",
+          "readOnly": true
         },
         "curveName": {
           "type": "string",
diff --git a/specification/keyvault/resource-manager/Microsoft.KeyVault/stable/2019-09-01/keyvault.json b/specification/keyvault/resource-manager/Microsoft.KeyVault/stable/2019-09-01/keyvault.json
index 3c2bf71f348a..362650353068 100644
--- a/specification/keyvault/resource-manager/Microsoft.KeyVault/stable/2019-09-01/keyvault.json
+++ b/specification/keyvault/resource-manager/Microsoft.KeyVault/stable/2019-09-01/keyvault.json
@@ -1261,6 +1261,11 @@
           "type": "string",
           "description": "The URI of the vault for performing operations on keys and secrets. This property is readonly"
         },
+        "hsmPoolResourceId": {
+          "type": "string",
+          "description": "The resource id of HSM Pool.",
+          "readOnly": true
+        },
         "enabledForDeployment": {
           "type": "boolean",
           "description": "Property to specify whether Azure Virtual Machines are permitted to retrieve certificates stored as secrets from the key vault."
@@ -1299,7 +1304,11 @@
           "x-ms-enum": {
             "name": "CreateMode",
             "modelAsString": false
-          }
+          },
+          "x-ms-mutability": [
+            "create",
+            "update"
+          ]
         },
         "enablePurgeProtection": {
           "type": "boolean",