diff --git a/protocol/pom.xml b/protocol/pom.xml
index 7938ede4b1..29569c5ab2 100755
--- a/protocol/pom.xml
+++ b/protocol/pom.xml
@@ -37,6 +37,14 @@
             <groupId>org.eclipse.ditto</groupId>
             <artifactId>ditto-json</artifactId>
         </dependency>
+        <dependency>
+            <groupId>org.eclipse.ditto</groupId>
+            <artifactId>ditto-things-model</artifactId>
+        </dependency>
+        <dependency>
+            <groupId>org.eclipse.ditto</groupId>
+            <artifactId>ditto-policies-model</artifactId>
+        </dependency>
         <dependency>
             <groupId>org.eclipse.ditto</groupId>
             <artifactId>ditto-thingsearch-model</artifactId>