diff --git a/tx-backend/pom.xml b/tx-backend/pom.xml
index 3d29fde5b0..f5c90181d0 100644
--- a/tx-backend/pom.xml
+++ b/tx-backend/pom.xml
@@ -17,11 +17,11 @@
 
     <dependencies>
         <!-- tx-application modules -->
-    <!--    <dependency>
-            <groupId>org.eclipse.tractusx.traceability</groupId>
-            <artifactId>tx-models</artifactId>
-            <version>0.0.1-SNAPSHOT</version>
-        </dependency>-->
+        <!--    <dependency>
+                <groupId>org.eclipse.tractusx.traceability</groupId>
+                <artifactId>tx-models</artifactId>
+                <version>0.0.1-SNAPSHOT</version>
+            </dependency>-->
 
         <!-- managed by spring boot -->
         <dependency>
@@ -221,6 +221,12 @@
             <version>${commons-io.version}</version>
         </dependency>
 
+        <dependency>
+            <groupId>org.apache.commons</groupId>
+            <artifactId>commons-collections4</artifactId>
+            <version>4.4</version>
+        </dependency>
+
         <dependency> <!-- use a specific Groovy version rather than the one specified by spock-core -->
             <groupId>org.apache.groovy</groupId>
             <artifactId>groovy</artifactId>
@@ -344,12 +350,6 @@
     <build>
         <finalName>traceability-app-${project.version}</finalName>
         <plugins>
-         <!--   <plugin>
-                <groupId>org.eclipse.dash</groupId>
-                <artifactId>license-tool-plugin</artifactId>
-                <version>${eclipse-license-tool.version}</version>
-            </plugin>-->
-
             <plugin>
                 <groupId>org.apache.maven.plugins</groupId>
                 <artifactId>maven-resources-plugin</artifactId>
@@ -587,35 +587,35 @@
         <profile>
             <id>spotbugs-check</id>
             <build>
-            <plugins>
-            <plugin>
-                <groupId>com.github.spotbugs</groupId>
-                <artifactId>spotbugs-maven-plugin</artifactId>
-                <version>${spotbugs-plugin.version}</version>
-                <configuration>
-                    <effort>Max</effort>
-                    <threshold>Low</threshold>
-                    <xmlOutput>true</xmlOutput>
-                    <failThreshold>High</failThreshold>
-                    <excludeFilterFile>ci/spotbugs-excludes.xml</excludeFilterFile>
-                    <plugins>
-                        <plugin>
-                            <groupId>com.h3xstream.findsecbugs</groupId>
-                            <artifactId>findsecbugs-plugin</artifactId>
-                            <version>${findsecbugs-plugin.version}</version>
-                        </plugin>
-                    </plugins>
-                </configuration>
-                <executions>
-                    <execution>
-                        <phase>validate</phase>
-                        <goals>
-                            <goal>check</goal>
-                        </goals>
-                    </execution>
-                </executions>
-            </plugin>
-            </plugins>
+                <plugins>
+                    <plugin>
+                        <groupId>com.github.spotbugs</groupId>
+                        <artifactId>spotbugs-maven-plugin</artifactId>
+                        <version>${spotbugs-plugin.version}</version>
+                        <configuration>
+                            <effort>Max</effort>
+                            <threshold>Low</threshold>
+                            <xmlOutput>true</xmlOutput>
+                            <failThreshold>High</failThreshold>
+                            <excludeFilterFile>ci/spotbugs-excludes.xml</excludeFilterFile>
+                            <plugins>
+                                <plugin>
+                                    <groupId>com.h3xstream.findsecbugs</groupId>
+                                    <artifactId>findsecbugs-plugin</artifactId>
+                                    <version>${findsecbugs-plugin.version}</version>
+                                </plugin>
+                            </plugins>
+                        </configuration>
+                        <executions>
+                            <execution>
+                                <phase>validate</phase>
+                                <goals>
+                                    <goal>check</goal>
+                                </goals>
+                            </execution>
+                        </executions>
+                    </plugin>
+                </plugins>
             </build>
         </profile>
         <profile>
diff --git a/tx-backend/src/main/java/org/eclipse/tractusx/traceability/assets/domain/service/AssetService.java b/tx-backend/src/main/java/org/eclipse/tractusx/traceability/assets/domain/service/AssetService.java
index 9fd7116fd0..9557f81dbb 100644
--- a/tx-backend/src/main/java/org/eclipse/tractusx/traceability/assets/domain/service/AssetService.java
+++ b/tx-backend/src/main/java/org/eclipse/tractusx/traceability/assets/domain/service/AssetService.java
@@ -34,10 +34,15 @@
 import org.springframework.stereotype.Component;
 
 import java.util.ArrayList;
+import java.util.Collections;
 import java.util.List;
 import java.util.Map;
+import java.util.Optional;
 import java.util.function.Function;
 import java.util.stream.Collectors;
+import java.util.stream.Stream;
+
+import static org.apache.commons.collections4.CollectionUtils.emptyIfNull;
 
 @Component
 public class AssetService {
@@ -75,11 +80,21 @@ public void synchronizeAssets(String globalAssetId) {
         }
     }
 
+    /**
+     * Combines the list of downward assets with the list of upward assets by merging the parent descriptions of
+     * matching child assets into the corresponding downward assets. If an upward asset has no matching downward asset,
+     * it is added to the result list as is.
+     *
+     * @param downwardAssets the list of downward assets to be combined with the upward assets
+     * @param upwardAssets   the list of upward assets to be combined with the downward assets
+     * @return a new list of {@link Asset} objects that contains the combined assets with merged parent descriptions
+     */
     public List<Asset> combineAssetsAndMergeParentDescriptionIntoDownwardAssets(List<Asset> downwardAssets, List<Asset> upwardAssets) {
-        Map<String, Asset> downwardAssetsMap = downwardAssets.stream()
+
+        Map<String, Asset> downwardAssetsMap = emptyIfNull(downwardAssets).stream()
                 .collect(Collectors.toMap(Asset::getId, Function.identity()));
 
-        return upwardAssets.stream()
+        return emptyIfNull(upwardAssets).stream()
                 .map(parentAsset -> {
                     Asset matchingChildAsset = downwardAssetsMap.get(parentAsset.getId());
                     if (matchingChildAsset == null) {