diff --git a/xml/dtd/pentestreport.xsd b/xml/dtd/pentestreport.xsd
index 61b0219..51fcdba 100644
--- a/xml/dtd/pentestreport.xsd
+++ b/xml/dtd/pentestreport.xsd
@@ -41,7 +41,7 @@
 
   <xs:element name="meta">
     <xs:complexType>
-      <xs:sequence>
+      <xs:all>
         <xs:element ref="title" minOccurs="1"/>
         <xs:element ref="subtitle" minOccurs="0"/>
         <xs:element ref="client_reference" minOccurs="0"/>
@@ -52,32 +52,32 @@
         <xs:element ref="classification"/>
         <xs:element ref="version_history"/>
         <xs:element ref="company"/>
-      </xs:sequence>
+      </xs:all>
     </xs:complexType>
   </xs:element>
 
   <xs:element name="activityinfo">
     <xs:complexType>
-      <xs:sequence>
-        <xs:element ref="duration" minOccurs="1" maxOccurs="1"/>
-        <xs:element ref="persondays" minOccurs="1" maxOccurs="1"/>
-        <xs:element ref="planning" minOccurs="1" maxOccurs="1"/>
-        <xs:element ref="report_due" minOccurs="1" maxOccurs="1"/>
-        <xs:element ref="nature" minOccurs="1" maxOccurs="1"/>
-        <xs:element ref="type" minOccurs="1" maxOccurs="1"/>
-        <xs:element minOccurs="0" maxOccurs="1" ref="target_application"/>
-        <xs:element minOccurs="0" maxOccurs="1" ref="target_application_producer"/>
-      </xs:sequence>
+      <xs:all>
+        <xs:element ref="duration"/>
+        <xs:element ref="persondays"/>
+        <xs:element ref="planning"/>
+        <xs:element ref="report_due"/>
+        <xs:element ref="nature"/>
+        <xs:element ref="type"/>
+        <xs:element minOccurs="0" ref="target_application"/>
+        <xs:element minOccurs="0" ref="target_application_producer"/>
+      </xs:all>
     </xs:complexType>
   </xs:element>
 
   <xs:element name="collaborators">
     <xs:complexType>
-      <xs:sequence>
+      <xs:all>
         <xs:element ref="reviewers"/>
         <xs:element ref="approver"/>
         <xs:element ref="pentesters"/>
-      </xs:sequence>
+      </xs:all>
     </xs:complexType>
   </xs:element>