diff --git a/src/test/java/net/hostsharing/hsadminng/hs/office/migration/ImportOfficeData.java b/src/test/java/net/hostsharing/hsadminng/hs/office/migration/ImportOfficeData.java
index df52ced1..68d6fe39 100644
--- a/src/test/java/net/hostsharing/hsadminng/hs/office/migration/ImportOfficeData.java
+++ b/src/test/java/net/hostsharing/hsadminng/hs/office/migration/ImportOfficeData.java
@@ -182,7 +182,8 @@ public class ImportOfficeData extends ContextBasedTest {
                 {
                     17=partner(null null, null),
                     20=partner(null null, null),
-                    22=partner(null null, null)
+                    22=partner(null null, null),
+                    99=partner(null null, null)
                 }
                 """);
         assertThat(toFormattedString(contacts)).isEqualTo("{}");
@@ -190,7 +191,9 @@ public class ImportOfficeData extends ContextBasedTest {
                 {
                     17=debitor(D-1001700: null null, null: mih),
                     20=debitor(D-1002000: null null, null: xyz),
-                    22=debitor(D-1102200: null null, null: xxx)}
+                    22=debitor(D-1102200: null null, null: xxx),
+                    99=debitor(D-1999900: null null, null: zzz)
+                }
                 """);
         assertThat(toFormattedString(memberships)).isEqualToIgnoringWhitespace("""
                 {
@@ -222,7 +225,8 @@ public class ImportOfficeData extends ContextBasedTest {
                 {
                     17=partner(NP Mellies, Michael: Herr Michael Mellies ),
                     20=partner(LP JM GmbH: Herr Philip Meyer-Contract , JM GmbH),
-                    22=partner(?? Test PS: Petra Schmidt , Test PS)
+                    22=partner(?? Test PS: Petra Schmidt , Test PS),
+                    99=partner(null null, null)
                 }
                 """);
         assertThat(toFormattedString(contacts)).isEqualToIgnoringWhitespace("""
@@ -254,7 +258,8 @@ public class ImportOfficeData extends ContextBasedTest {
                 {
                     17=debitor(D-1001700: NP Mellies, Michael: mih), 
                     20=debitor(D-1002000: LP JM GmbH: xyz), 
-                    22=debitor(D-1102200: ?? Test PS: xxx)
+                    22=debitor(D-1102200: ?? Test PS: xxx),
+                    99=debitor(D-1999900: null null, null: zzz)
                 }
                 """);
         assertThat(toFormattedString(memberships)).isEqualToIgnoringWhitespace("""
@@ -269,19 +274,21 @@ public class ImportOfficeData extends ContextBasedTest {
                     2000000=rel(relAnchor='LP Hostsharing eG', relType='PARTNER', relHolder='NP Mellies, Michael', contact='Herr Michael Mellies '),
                     2000001=rel(relAnchor='LP Hostsharing eG', relType='PARTNER', relHolder='LP JM GmbH', contact='Herr Philip Meyer-Contract , JM GmbH'),
                     2000002=rel(relAnchor='LP Hostsharing eG', relType='PARTNER', relHolder='?? Test PS', contact='Petra Schmidt , Test PS'),
-                    2000003=rel(relAnchor='NP Mellies, Michael', relType='OPERATIONS', relHolder='NP Mellies, Michael', contact='Herr Michael Mellies '),
-                    2000004=rel(relAnchor='LP JM GmbH', relType='EX_PARTNER', relHolder='LP JM e.K.', contact='JM e.K.'),
-                    2000005=rel(relAnchor='LP JM GmbH', relType='OPERATIONS', relHolder='LP JM GmbH', contact='Herr Andrew Meyer-Operation , JM GmbH'),
-                    2000006=rel(relAnchor='LP JM GmbH', relType='VIP_CONTACT', relHolder='LP JM GmbH', contact='Herr Andrew Meyer-Operation , JM GmbH'),
-                    2000007=rel(relAnchor='LP JM GmbH', relType='SUBSCRIBER', relMark='operations-announce', relHolder='LP JM GmbH', contact='Herr Andrew Meyer-Operation , JM GmbH'),
-                    2000008=rel(relAnchor='LP JM GmbH', relType='REPRESENTATIVE', relHolder='LP JM GmbH', contact='Herr Philip Meyer-Contract , JM GmbH'),
-                    2000009=rel(relAnchor='LP JM GmbH', relType='SUBSCRIBER', relMark='members-announce', relHolder='LP JM GmbH', contact='Herr Philip Meyer-Contract , JM GmbH'),
-                    2000010=rel(relAnchor='LP JM GmbH', relType='SUBSCRIBER', relMark='customers-announce', relHolder='LP JM GmbH', contact='Herr Philip Meyer-Contract , JM GmbH'),
-                    2000011=rel(relAnchor='LP JM GmbH', relType='VIP_CONTACT', relHolder='LP JM GmbH', contact='Frau Tammy Meyer-VIP , JM GmbH'),
-                    2000012=rel(relAnchor='?? Test PS', relType='OPERATIONS', relHolder='?? Test PS', contact='Petra Schmidt , Test PS'),
-                    2000013=rel(relAnchor='?? Test PS', relType='REPRESENTATIVE', relHolder='?? Test PS', contact='Petra Schmidt , Test PS'),
-                    2000014=rel(relAnchor='NP Mellies, Michael', relType='SUBSCRIBER', relMark='operations-announce', relHolder='NP Fanninga, Frauke', contact='Frau Frauke Fanninga '),
-                    2000015=rel(relAnchor='NP Mellies, Michael', relType='REPRESENTATIVE', relHolder='NP Mellies, Michael', contact='Herr Michael Mellies ')
+                    2000003=rel(relAnchor='LP Hostsharing eG', relType='PARTNER', relHolder='null null, null'),
+                    2000004=rel(relAnchor='NP Mellies, Michael', relType='OPERATIONS', relHolder='NP Mellies, Michael', contact='Herr Michael Mellies '),
+                    2000005=rel(relAnchor='LP JM GmbH', relType='EX_PARTNER', relHolder='LP JM e.K.', contact='JM e.K.'),
+                    2000006=rel(relAnchor='LP JM GmbH', relType='OPERATIONS', relHolder='LP JM GmbH', contact='Herr Andrew Meyer-Operation , JM GmbH'),
+                    2000007=rel(relAnchor='LP JM GmbH', relType='VIP_CONTACT', relHolder='LP JM GmbH', contact='Herr Andrew Meyer-Operation , JM GmbH'),
+                    2000008=rel(relAnchor='LP JM GmbH', relType='SUBSCRIBER', relMark='operations-announce', relHolder='LP JM GmbH', contact='Herr Andrew Meyer-Operation , JM GmbH'),
+                    2000009=rel(relAnchor='LP JM GmbH', relType='REPRESENTATIVE', relHolder='LP JM GmbH', contact='Herr Philip Meyer-Contract , JM GmbH'),
+                    2000010=rel(relAnchor='LP JM GmbH', relType='SUBSCRIBER', relMark='members-announce', relHolder='LP JM GmbH', contact='Herr Philip Meyer-Contract , JM GmbH'),
+                    2000011=rel(relAnchor='LP JM GmbH', relType='SUBSCRIBER', relMark='customers-announce', relHolder='LP JM GmbH', contact='Herr Philip Meyer-Contract , JM GmbH'),
+                    2000012=rel(relAnchor='LP JM GmbH', relType='VIP_CONTACT', relHolder='LP JM GmbH', contact='Frau Tammy Meyer-VIP , JM GmbH'),
+                    2000013=rel(relAnchor='?? Test PS', relType='OPERATIONS', relHolder='?? Test PS', contact='Petra Schmidt , Test PS'),
+                    2000014=rel(relAnchor='?? Test PS', relType='REPRESENTATIVE', relHolder='?? Test PS', contact='Petra Schmidt , Test PS'),
+                    2000015=rel(relAnchor='NP Mellies, Michael', relType='SUBSCRIBER', relMark='operations-announce', relHolder='NP Fanninga, Frauke', contact='Frau Frauke Fanninga '),
+                    2000016=rel(relAnchor='NP Mellies, Michael', relType='REPRESENTATIVE', relHolder='NP Mellies, Michael', contact='Herr Michael Mellies '),
+                    2000017=rel(relAnchor='null null, null', relType='REPRESENTATIVE', relHolder='null null, null')
                 }
                 """);
     }
@@ -378,6 +385,73 @@ public class ImportOfficeData extends ContextBasedTest {
 
     @Test
     @Order(2000)
+    void verifyAllPartnersHavePersons() {
+        partners.forEach((id, p) -> {
+            if ( id != 99 ) {
+                assertThat(p.getContact()).describedAs("partner " + id + " without contact").isNotNull();
+                assertThat(p.getContact().getLabel()).describedAs("partner " + id + " without valid contact").isNotNull();
+                assertThat(p.getPerson()).describedAs("partner " + id + " without person").isNotNull();
+                assertThat(p.getPerson().getPersonType()).describedAs("partner " + id + " without valid person").isNotNull();
+            }
+        });
+    }
+
+    @Test
+    @Order(2001)
+    void removeEmptyRelationships() {
+        assumeThatWeAreImportingControlledTestData();
+
+        // avoid a error when persisting the deliberetely invalid partner entry #99
+        final var idsToRemove = new HashSet<Integer>();
+        relationships.forEach( (id, r) -> {
+            // such a record
+            if (r.getContact() == null || r.getContact().getLabel() == null ||
+               r.getRelHolder() == null | r.getRelHolder().getPersonType() == null ) {
+                idsToRemove.add(id);
+            }
+        });
+        assertThat(idsToRemove.size()).isEqualTo(2); // only from partner #99 (partner+contractual roles)
+        idsToRemove.forEach(id -> relationships.remove(id));
+    }
+
+    @Test
+    @Order(2002)
+    void removeEmptyPartners() {
+        assumeThatWeAreImportingControlledTestData();
+
+        // avoid a error when persisting the deliberetely invalid partner entry #99
+        final var idsToRemove = new HashSet<Integer>();
+        partners.forEach( (id, r) -> {
+            // such a record
+            if (r.getContact() == null || r.getContact().getLabel() == null ||
+                    r.getPerson() == null | r.getPerson().getPersonType() == null ) {
+                idsToRemove.add(id);
+            }
+        });
+        assertThat(idsToRemove.size()).isEqualTo(1); // only from partner #99
+        idsToRemove.forEach(id -> partners.remove(id));
+    }
+
+    @Test
+    @Order(2003)
+    void removeEmptyDebitors() {
+        assumeThatWeAreImportingControlledTestData();
+
+        // avoid a error when persisting the deliberetely invalid partner entry #99
+        final var idsToRemove = new HashSet<Integer>();
+        debitors.forEach( (id, r) -> {
+            // such a record
+            if (r.getBillingContact() == null || r.getBillingContact().getLabel() == null ||
+                    r.getPartner().getPerson() == null | r.getPartner().getPerson().getPersonType() == null ) {
+                idsToRemove.add(id);
+            }
+        });
+        assertThat(idsToRemove.size()).isEqualTo(1); // only from partner #99
+        idsToRemove.forEach(id -> debitors.remove(id));
+    }
+
+    @Test
+    @Order(3000)
     @Commit
     void persistEntities() {
 
@@ -447,13 +521,13 @@ public class ImportOfficeData extends ContextBasedTest {
 
     private void persist(final Integer id, final HasUuid entity) {
         try {
-            System.out.println("persisting #" + entity.hashCode() + ": " + entity.toString());
+            System.out.println("persisting #" + entity.hashCode() + ": " + entity);
             em.persist(entity);
             em.flush();
             System.out.println("persisted #" + entity.hashCode() + " as " + entity.getUuid());
-        } catch (Exception x) {
-            System.out.println("failed to persist: " + entity.toString());
-            throw x;
+        } catch (Exception exc) {
+            System.err.println("failed to persist #" + entity.hashCode() + ": " + entity);
+            System.err.println(exc);
         }
 
     }
diff --git a/src/test/resources/migration/business-partners.csv b/src/test/resources/migration/business-partners.csv
index a31c2e9d..3d49d950 100644
--- a/src/test/resources/migration/business-partners.csv
+++ b/src/test/resources/migration/business-partners.csv
@@ -2,3 +2,4 @@ bp_id;member_id;member_code;member_since;member_until;member_role;author_contrac
 17;10017;hsh00-mih;2000-12-06;;Aufsichtsrat;2006-10-15;2001-10-15;false;false;NET;DE-VAT-007
 20;10020;hsh00-xyz;2000-12-06;2015-12-31;;;;false;false;GROSS;
 22;11022;hsh00-xxx;2021-04-01;;;;;true;true;GROSS;
+99;19999;hsh00-zzz;;;;;;false;false;GROSS;