diff --git a/mdx/aaf/aaf-import.xml b/mdx/aaf/aaf-import.xml
index c2729602..46789966 100644
--- a/mdx/aaf/aaf-import.xml
+++ b/mdx/aaf/aaf-import.xml
@@ -21,7 +21,10 @@
             <list>
                 <ref bean="fetchAafExportAggregate"/>
                 <ref bean="checkAafSignature"/>
-                <ref bean="errorAnnouncingFilter"/><!-- should be fatal -->
+                
+                <!-- failure to validate signature is fatal -->
+                <ref bean="errorTerminatingFilter"/>
+                
                 <ref bean="disassemble"/>
                 
                 <ref bean="standardImportActions"/>
diff --git a/mdx/arnes/arnes-import.xml b/mdx/arnes/arnes-import.xml
index cddc2f74..da3f39e6 100644
--- a/mdx/arnes/arnes-import.xml
+++ b/mdx/arnes/arnes-import.xml
@@ -21,7 +21,10 @@
             <list>
                 <ref bean="fetchArnesExportAggregate"/>
                 <ref bean="checkArnesSignature"/>
-                <ref bean="errorAnnouncingFilter"/><!-- should be fatal -->
+
+                <!-- failure to validate signature is fatal -->
+                <ref bean="errorTerminatingFilter"/>
+                
                 <ref bean="disassemble"/>
                 
                 <ref bean="standardImportActions"/>
diff --git a/mdx/caf/caf-import.xml b/mdx/caf/caf-import.xml
index 6ab50940..6ea3453b 100644
--- a/mdx/caf/caf-import.xml
+++ b/mdx/caf/caf-import.xml
@@ -21,7 +21,10 @@
             <list>
                 <ref bean="fetchCafExportAggregate"/>
                 <ref bean="checkCafSignature"/>
-                <ref bean="errorAnnouncingFilter"/><!-- should be fatal -->
+                
+                <!-- failure to validate signature is fatal -->
+                <ref bean="errorTerminatingFilter"/>
+                
                 <ref bean="disassemble"/>
                 
                 <ref bean="standardImportActions"/>
diff --git a/mdx/common-beans.xml b/mdx/common-beans.xml
index bc7e25a6..fdc938a8 100644
--- a/mdx/common-beans.xml
+++ b/mdx/common-beans.xml
@@ -124,6 +124,18 @@
         <property name="id" value="errorAnnouncingFilter"/>
     </bean>
     
+    <!--
+        errorTerminatingFilter
+        
+        A pipeline stage that checks for any errors, and then announces
+        and filters any encountered.
+    -->
+    <bean id="errorTerminatingFilter" class="uk.org.ukfederation.mda.ErrorAnnouncingFilteringStage"
+        init-method="initialize" lazy-init="true">
+        <property name="id" value="errorTerminatingFilter"/>
+        <property name="terminating" value="true"/>
+    </bean>
+    
     <!--
         cleanImport
         
diff --git a/mdx/edugain/edugain-import.xml b/mdx/edugain/edugain-import.xml
index ac489743..e12f7deb 100644
--- a/mdx/edugain/edugain-import.xml
+++ b/mdx/edugain/edugain-import.xml
@@ -25,7 +25,10 @@
             <list>
                 <ref bean="fetchEduGainAggregate"/>
                 <ref bean="checkEdugainSignature"/>
-                <ref bean="errorAnnouncingFilter"/><!-- should be fatal -->
+                
+                <!-- failure to validate signature is fatal -->
+                <ref bean="errorTerminatingFilter"/>
+                
                 <ref bean="disassemble"/>
                 
                 <ref bean="standardImportActions"/>
diff --git a/mdx/edugain/edugain-test-import.xml b/mdx/edugain/edugain-test-import.xml
index 5700560a..f742a769 100644
--- a/mdx/edugain/edugain-test-import.xml
+++ b/mdx/edugain/edugain-test-import.xml
@@ -25,7 +25,10 @@
             <list>
                 <ref bean="fetchEduGainTestAggregate"/>
                 <ref bean="checkEdugainSignature"/>
-                <ref bean="errorAnnouncingFilter"/><!-- should be fatal -->
+                
+                <!-- failure to validate signature is fatal -->
+                <ref bean="errorTerminatingFilter"/>
+                
                 <ref bean="disassemble"/>
                 
                 <ref bean="standardImportActions"/>
diff --git a/mdx/edugate/edugate-import.xml b/mdx/edugate/edugate-import.xml
index e18d2f57..7d20d474 100644
--- a/mdx/edugate/edugate-import.xml
+++ b/mdx/edugate/edugate-import.xml
@@ -21,7 +21,10 @@
             <list>
                 <ref bean="fetchEdugateExportAggregate"/>
                 <ref bean="checkEdugateSignature"/>
-                <ref bean="errorAnnouncingFilter"/><!-- should be fatal -->
+                
+                <!-- failure to validate signature is fatal -->
+                <ref bean="errorTerminatingFilter"/>
+                
                 <ref bean="disassemble"/>
                 
                 <ref bean="standardImportActions"/>
diff --git a/mdx/incommon/incommon-import.xml b/mdx/incommon/incommon-import.xml
index 4a4d8855..0b4c2666 100644
--- a/mdx/incommon/incommon-import.xml
+++ b/mdx/incommon/incommon-import.xml
@@ -21,7 +21,10 @@
             <list>
                 <ref bean="fetchInCommonExportAggregate"/>
                 <ref bean="checkInCommonSignature"/>
-                <ref bean="errorAnnouncingFilter"/><!-- should be fatal -->
+                
+                <!-- failure to validate signature is fatal -->
+                <ref bean="errorTerminatingFilter"/>
+                
                 <ref bean="disassemble"/>
                 
                 <ref bean="standardImportActions"/>
diff --git a/mdx/swamid/swamid-import.xml b/mdx/swamid/swamid-import.xml
index 65b2bfdd..2aacce31 100644
--- a/mdx/swamid/swamid-import.xml
+++ b/mdx/swamid/swamid-import.xml
@@ -21,7 +21,10 @@
             <list>
                 <ref bean="fetchSwamidExportAggregate"/>
                 <ref bean="checkSwamidSignature"/>
-                <ref bean="errorAnnouncingFilter"/><!-- should be fatal -->
+                
+                <!-- failure to validate signature is fatal -->
+                <ref bean="errorTerminatingFilter"/>
+                
                 <ref bean="disassemble"/>
                 
                 <ref bean="standardImportActions"/>
diff --git a/mdx/switch/switch-import.xml b/mdx/switch/switch-import.xml
index eab3fd0c..2709b382 100644
--- a/mdx/switch/switch-import.xml
+++ b/mdx/switch/switch-import.xml
@@ -21,7 +21,10 @@
             <list>
                 <ref bean="fetchSwitchExportAggregate"/>
                 <ref bean="checkSwitchSignature"/>
-                <ref bean="errorAnnouncingFilter"/><!-- should be fatal -->
+                
+                <!-- failure to validate signature is fatal -->
+                <ref bean="errorTerminatingFilter"/>
+                
                 <ref bean="disassemble"/>
                 
                 <ref bean="standardImportActions"/>
diff --git a/mdx/uk/uk-collect.xml b/mdx/uk/uk-collect.xml
index bb44ebde..54f0e397 100644
--- a/mdx/uk/uk-collect.xml
+++ b/mdx/uk/uk-collect.xml
@@ -99,7 +99,10 @@
                 <ref bean="populateItemIds"/>
                 <ref bean="checkSchemas"/>
                 <ref bean="CHECK.std"/>
-                <ref bean="errorAnnouncingFilter"/><!-- should be fatal -->
+                
+                <!-- failure of any check on registered metadata is fatal -->
+                <ref bean="errorTerminatingFilter"/>
+                
                 <ref bean="assemble.uk"/>
 
                 <!--
@@ -124,7 +127,9 @@
                     fixed to use a parameter.
                 -->
                 <ref bean="check_check"/>
-                <ref bean="errorAnnouncingFilter"/><!-- should be fatal -->
+                
+                <!-- failure of any check on registered metadata is fatal -->
+                <ref bean="errorTerminatingFilter"/>
 
                 <ref bean="normaliseNamespaces"/>
             </list>
diff --git a/tools/ukf-mda/ukf-mda-0.6-SNAPSHOT.jar b/tools/ukf-mda/ukf-mda-0.6-SNAPSHOT.jar
index 39294c35..066102bd 100644
Binary files a/tools/ukf-mda/ukf-mda-0.6-SNAPSHOT.jar and b/tools/ukf-mda/ukf-mda-0.6-SNAPSHOT.jar differ