diff --git a/src/main/java/ch/usi/inf/sa4/sanmarinoes/smarthut/controller/BooleanTriggerController.java b/src/main/java/ch/usi/inf/sa4/sanmarinoes/smarthut/controller/BooleanTriggerController.java
index 927b66c..9331b56 100644
--- a/src/main/java/ch/usi/inf/sa4/sanmarinoes/smarthut/controller/BooleanTriggerController.java
+++ b/src/main/java/ch/usi/inf/sa4/sanmarinoes/smarthut/controller/BooleanTriggerController.java
@@ -29,7 +29,7 @@ public class BooleanTriggerController {
         return booleanTriggerRepository.findAllByAutomationId(automationId);
     }
 
-    private BooleanTrigger<?> save(BooleanTrigger newRL, BooleanTriggerSaveRequest s) {
+    private BooleanTrigger<?> save(BooleanTrigger<?> newRL, BooleanTriggerSaveRequest s) {
         newRL.setDeviceId(s.getDeviceId());
         newRL.setAutomationId(s.getAutomationId());
         newRL.setOn(s.isOn());
@@ -40,7 +40,7 @@ public class BooleanTriggerController {
     @PostMapping
     public BooleanTrigger<?> create(
             @Valid @RequestBody BooleanTriggerSaveRequest booleanTriggerSaveRequest) {
-        return save(new BooleanTrigger(), booleanTriggerSaveRequest);
+        return save(new BooleanTrigger<>(), booleanTriggerSaveRequest);
     }
 
     @PutMapping
diff --git a/src/main/java/ch/usi/inf/sa4/sanmarinoes/smarthut/models/DeviceRepository.java b/src/main/java/ch/usi/inf/sa4/sanmarinoes/smarthut/models/DeviceRepository.java
index cf5c004..d1f828d 100644
--- a/src/main/java/ch/usi/inf/sa4/sanmarinoes/smarthut/models/DeviceRepository.java
+++ b/src/main/java/ch/usi/inf/sa4/sanmarinoes/smarthut/models/DeviceRepository.java
@@ -14,6 +14,10 @@ import org.springframework.data.repository.query.Param;
 public interface DeviceRepository<T extends Device> extends CrudRepository<T, Long> {
     List<T> findByRoomId(@Param("roomId") long roomId);
 
+    @Query(
+            "SELECT COUNT(d) FROM Device d JOIN d.room r JOIN r.user u WHERE d.name = ?1 AND u.username = ?2")
+    Integer findDuplicates(String name, String username);
+
     /**
      * Finds devices by their id and a username
      *
diff --git a/src/main/java/ch/usi/inf/sa4/sanmarinoes/smarthut/service/DeviceService.java b/src/main/java/ch/usi/inf/sa4/sanmarinoes/smarthut/service/DeviceService.java
index 87df762..0bc2a6e 100644
--- a/src/main/java/ch/usi/inf/sa4/sanmarinoes/smarthut/service/DeviceService.java
+++ b/src/main/java/ch/usi/inf/sa4/sanmarinoes/smarthut/service/DeviceService.java
@@ -29,7 +29,15 @@ public class DeviceService {
         roomRepository.findByIdAndUsername(roomId, username).orElseThrow(NotFoundException::new);
     }
 
-    public void triggerTriggers(Device device) {
+    private void renameIfDuplicate(Device toCreate, String username) {
+        while (deviceRepository.findDuplicates(toCreate.getName(), username)
+                        - (toCreate.getId() <= 0 ? 0 : 1)
+                > 0) {
+            toCreate.setName(toCreate.getName() + " (new)");
+        }
+    }
+
+    private void triggerTriggers(Device device) {
 
         final long deviceId = device.getId();
 
@@ -107,6 +115,8 @@ public class DeviceService {
         final User currentUser = userRepository.findByUsername(guestUsername);
         final User host = userRepository.findById(hostId).orElseThrow(NotFoundException::new);
         if (!host.getGuests().contains(currentUser)) throw new NotFoundException();
+        renameIfDuplicate(device, host.getUsername());
+        device = deviceRepository.save(device);
         final Set<User> guests = Set.copyOf(host.getGuests());
 
         // We're telling the host that a guest has modified a device. Therefore, fromGuest becomes
@@ -145,6 +155,7 @@ public class DeviceService {
 
     public <T extends Device> List<T> saveAllAsOwner(
             Iterable<T> devices, String username, boolean fromScene) {
+        devices.forEach(d -> renameIfDuplicate(d, username));
         devices = deviceRepository.saveAll(devices);
         devices.forEach((d) -> propagateUpdateAsOwner(d, username));
 
@@ -156,6 +167,7 @@ public class DeviceService {
     }
 
     public <T extends Device> T saveAsOwner(T device, String username, boolean fromScene) {
+        renameIfDuplicate(device, username);
         device = deviceRepository.save(device);
         propagateUpdateAsOwner(device, username);