diff --git a/docs/changelog.md b/docs/changelog.md
index 392916cd..f7bd0f99 100644
--- a/docs/changelog.md
+++ b/docs/changelog.md
@@ -1,6 +1,7 @@
 ## Unreleased
 
 - Fixed an NPE in the assertion route
+- Generate valid XON when the FHIR Organization identifier has no system [165](https://github.com/i4mi/MobileAccessGateway/issues/165)
 
 ## 2024/05/15 v070
 - support for multiple IDP's [128](https://github.com/i4mi/MobileAccessGateway/issues/128)
diff --git a/src/main/java/ch/bfh/ti/i4mi/mag/mhd/iti65/Iti65RequestConverter.java b/src/main/java/ch/bfh/ti/i4mi/mag/mhd/iti65/Iti65RequestConverter.java
index 3e941f03..9685a830 100644
--- a/src/main/java/ch/bfh/ti/i4mi/mag/mhd/iti65/Iti65RequestConverter.java
+++ b/src/main/java/ch/bfh/ti/i4mi/mag/mhd/iti65/Iti65RequestConverter.java
@@ -1000,17 +1000,21 @@ public Telecom transform(ContactPoint contactPoint) {
     }
 
 	/**
-	 * FHIR Organization -> XDS Organization
+	 * FHIR Organization -> IPF Organization (XDS XON)
 	 * @param org
 	 * @return
 	 */
 	public org.openehealth.ipf.commons.ihe.xds.core.metadata.Organization transform(Organization org) {
-		org.openehealth.ipf.commons.ihe.xds.core.metadata.Organization result = new org.openehealth.ipf.commons.ihe.xds.core.metadata.Organization();
+		final var result = new org.openehealth.ipf.commons.ihe.xds.core.metadata.Organization();
     	result.setOrganizationName(org.getName());
-    	Identifier identifier = org.getIdentifierFirstRep();
+    	final Identifier identifier = org.getIdentifierFirstRep();
     	if (identifier != null) {
-    		result.setIdNumber(identifier.getValue());
-    		result.setAssigningAuthority(new AssigningAuthority(noPrefix(identifier.getSystem())));
+			if (identifier.hasValue()) {
+				result.setIdNumber(identifier.getValue());
+			}
+			if (identifier.hasSystem()) {
+				result.setAssigningAuthority(new AssigningAuthority(noPrefix(identifier.getSystem())));
+			}
     	}
     	return result;
     }
diff --git a/src/test/java/ch/bfh/ti/i4mi/mag/mhd/iti65/Iti65RequestConverterTest.java b/src/test/java/ch/bfh/ti/i4mi/mag/mhd/iti65/Iti65RequestConverterTest.java
new file mode 100644
index 00000000..e45f71b4
--- /dev/null
+++ b/src/test/java/ch/bfh/ti/i4mi/mag/mhd/iti65/Iti65RequestConverterTest.java
@@ -0,0 +1,32 @@
+package ch.bfh.ti.i4mi.mag.mhd.iti65;
+
+import ca.uhn.hl7v2.HL7Exception;
+import org.hl7.fhir.r4.model.Organization;
+import org.junit.jupiter.api.Test;
+import org.openehealth.ipf.commons.ihe.xds.core.metadata.Hl7v2Based;
+
+import static org.junit.jupiter.api.Assertions.*;
+
+/**
+ * MobileAccessGateway
+ *
+ * @author Quentin Ligier
+ **/
+class Iti65RequestConverterTest {
+
+    @Test
+    void testTransformOrganization() {
+        Iti65RequestConverter iti65RequestConverter = new Iti65RequestConverter();
+
+        final var org = new Organization();
+        org.setName("Test");
+        org.addIdentifier().setValue("1234");
+
+        var xon = iti65RequestConverter.transform(org);
+        assertEquals("Test^^^^^^^^^1234", Hl7v2Based.render(xon));
+
+        org.getIdentifierFirstRep().setSystem("urn:oid:1.2.3");
+        xon = iti65RequestConverter.transform(org);
+        assertEquals("Test^^^^^&1.2.3&ISO^^^^1234", Hl7v2Based.render(xon));
+    }
+}
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