$ diff -u ngsiv2-draft-schema.orig.json ngsiv2-draft-schema.json
--- ngsiv2-draft-schema.orig.json	2019-04-08 12:23:44.103171653 +0200
+++ ngsiv2-draft-schema.json	2019-04-09 13:05:47.637837620 +0200
@@ -10,26 +10,6 @@
       "maxLength": 256,
       "pattern": "^[\\w\\-\\.\\{\\}\\$\\+\\*\\[\\]`|~^@!,:\\\\]+$"
     },
-    "Name": {
-      "allOf": [
-        {
-          "$ref": "#/definitions/Identifier"
-        },
-        {
-          "not": {
-            "type": "string",
-            "const": "geo:distance"
-          }
-        },
-        {
-          "not": {
-            "type": "string",
-            "const": "*"
-          }
-        }
-      ],
-      "description": "NGSIv2 Name"
-    },
     "Value": {
       "type": [
         "number",
@@ -40,13 +20,13 @@
         "string"
       ]
     },
-    "TypeValue": {
+    "AttributeTypeValue": {
       "type": "object",
       "properties": {
         "type": {
           "allOf": [
             {
-              "$ref": "#/definitions/Name"
+              "$ref": "#/definitions/Identifier"
             },
             {
               "not": {
@@ -68,6 +48,30 @@
         "value"
       ]
     },
+    "MetadataTypeValue": {
+      "type": "object",
+      "properties": {
+        "type": {
+          "allOf": [
+            {
+              "$ref": "#/definitions/Identifier"
+            },
+            {
+              "not": {
+                "const": "DateTime"
+              }
+            }
+          ]
+        },
+        "value": {
+          "$ref": "#/definitions/Value"
+        }
+      },
+      "required": [
+        "value"
+      ]
+    },
+
     "DateTimeValue": {
       "type": "string",
       "format": "date-time"
@@ -114,7 +118,7 @@
           "$ref": "#/definitions/DateTimeTypeValue"
         },
         "previousValue": {
-          "$ref": "#/definitions/TypeValue"
+          "$ref": "#/definitions/AttributeTypeValue"
         },
         "actionType": {
           "type": "object",
@@ -141,7 +145,7 @@
       "additionalProperties": {
         "anyOf": [
           {
-            "$ref": "#/definitions/TypeValue"
+            "$ref": "#/definitions/MetadataTypeValue"
           },
           {
             "$ref": "#/definitions/DateTimeTypeValue"
@@ -151,7 +155,10 @@
       "propertyNames": {
         "allOf": [
           {
-            "$ref": "#/definitions/Name"
+            "not": {
+              "type": "string",
+              "const": "*"
+            }
           }
         ]
       }
@@ -162,6 +169,9 @@
     "dateModified": {
       "$ref": "#/definitions/DateTimeTypeValue"
     },
+    "dateExpires": {
+      "$ref": "#/definitions/DateTimeTypeValue"
+    },
     "Attribute": {
       "allOf": [
         {
@@ -173,7 +183,7 @@
               "$ref": "#/definitions/GeoTypeValue"
             },
             {
-              "$ref": "#/definitions/TypeValue"
+              "$ref": "#/definitions/AttributeTypeValue"
             }
           ]
         },
@@ -196,7 +206,7 @@
         "type": {
           "allOf": [
             {
-              "$ref": "#/definitions/Name"
+              "$ref": "#/definitions/Identifier"
             },
             {
               "default": "Thing"
@@ -208,10 +218,26 @@
         },
         "dateModified": {
           "$ref": "#/definitions/dateModified"
+        },
+        "dateExpires": {
+          "$ref": "#/definitions/dateExpires"
         }
       },
       "propertyNames": {
-        "$ref": "#/definitions/Name"
+        "allOf": [
+          {
+            "not": {
+              "type": "string",
+              "const": "geo:distance"
+            }
+          },
+          {
+            "not": {
+              "type": "string",
+              "const": "*"
+            }
+          }
+        ]
       },
       "additionalProperties": {
         "anyOf": [