diff --git a/studymanager-services/src/main/java/io/redlink/more/studymanager/repository/ParticipantRepository.java b/studymanager-services/src/main/java/io/redlink/more/studymanager/repository/ParticipantRepository.java
index 96e9bfe7..5a4c03f0 100644
--- a/studymanager-services/src/main/java/io/redlink/more/studymanager/repository/ParticipantRepository.java
+++ b/studymanager-services/src/main/java/io/redlink/more/studymanager/repository/ParticipantRepository.java
@@ -86,7 +86,8 @@ ON CONFLICT (study_id, participant_id) DO UPDATE SET token = excluded.token
             "  AND p.status = 'active' " +
             "  AND  p.start IS NOT NULL " +
             "  AND COALESCE(sg.duration, s.duration) IS NOT NULL " +
-            "  AND (p.start + ((COALESCE(sg.duration, s.duration)->>'value')::int || ' ' || (COALESCE(sg.duration, s.duration)->>'unit'))::interval) < NOW()";
+            "  AND (p.start + ((COALESCE(sg.duration, s.duration)->>'value')::int || ' ' || (COALESCE(sg.duration, s.duration)->>'unit'))::interval) < NOW()" +
+            "GROUP BY p.study_id, p.participant_id";
 
     /*
      * SQL Statements for managing participant_observation_groups mapping for participants
diff --git a/studymanager-services/src/test/java/io/redlink/more/studymanager/repository/ParticipantRepositoryTest.java b/studymanager-services/src/test/java/io/redlink/more/studymanager/repository/ParticipantRepositoryTest.java
index 15285859..0b1f69b8 100644
--- a/studymanager-services/src/test/java/io/redlink/more/studymanager/repository/ParticipantRepositoryTest.java
+++ b/studymanager-services/src/test/java/io/redlink/more/studymanager/repository/ParticipantRepositoryTest.java
@@ -17,6 +17,7 @@
 import org.springframework.beans.factory.annotation.Autowired;
 import org.springframework.boot.autoconfigure.EnableAutoConfiguration;
 import org.springframework.boot.test.context.SpringBootTest;
+import org.springframework.scheduling.config.TaskExecutionOutcome;
 import org.springframework.test.annotation.DirtiesContext;
 import org.springframework.test.context.ActiveProfiles;
 import org.springframework.test.context.ContextConfiguration;
@@ -24,6 +25,7 @@
 import org.testcontainers.junit.jupiter.Container;
 import org.testcontainers.junit.jupiter.Testcontainers;
 
+import java.time.Instant;
 import java.util.Set;
 import java.util.concurrent.TimeUnit;
 
@@ -189,4 +191,16 @@ void testUndefinedStudyGroup() {
         assertThat(participant.getStudyGroupId()).isNull();
     }
 
+    @Test
+    @DisplayName("Participants for closing")
+    void testClosing() {
+        Study study = studyRepository.insert(new Study().setContact(new Contact().setPerson("test").setEmail("test")));
+        studyRepository.setStateById(study.getStudyId(), Study.Status.ACTIVE);
+        Participant participant = participantRepository
+                .insert(new Participant().setStudyId(study.getStudyId()).setRegistrationToken("abc").setStart(Instant.now()));
+        participantRepository.setStatusByIds(study.getStudyId(), participant.getParticipantId(), Participant.Status.ACTIVE);
+
+        var participants = participantRepository.listParticipantsForClosing();
+    }
+
 }