diff --git a/3.2/itop_design.xsd b/3.2/itop_design.xsd
index 86c0eee..4a83ae1 100644
--- a/3.2/itop_design.xsd
+++ b/3.2/itop_design.xsd
@@ -149,9 +149,10 @@
                                                     </xs:element>
                                                     <xs:element name="obsolescence" minOccurs="0">
                                                         <xs:complexType>
-                                                            <xs:sequence>
+                                                            <xs:sequence minOccurs="0">
                                                                 <xs:element name="condition" type="xs:string" />
                                                             </xs:sequence>
+                                                            <xs:attributeGroup ref="alteredNode" />
                                                         </xs:complexType>
                                                     </xs:element>
                                                     <xs:element name="uniqueness_rules" minOccurs="0">
diff --git a/test/datamodel.must-validate.xml b/test/datamodel.must-validate.xml
index 5c18774..0dfad4d 100644
--- a/test/datamodel.must-validate.xml
+++ b/test/datamodel.must-validate.xml
@@ -398,6 +398,11 @@
                 </summary>
             </presentation>
         </class>
+        <class id="TestDeleteIfExists" _delta="define_if_not_exists">
+            <properties>
+                <obsolescence _delta="delete_if_exists" />
+            </properties>
+        </class>
         <class id="TestAttributes">
             <fields>
                 <field id="blob" xsi:type="AttributeBlob" _delta="define">