diff --git a/scm-core/src/main/java/sonia/scm/group/GroupNames.java b/scm-core/src/main/java/sonia/scm/group/GroupNames.java
index 379c7ae0eb..2427101175 100644
--- a/scm-core/src/main/java/sonia/scm/group/GroupNames.java
+++ b/scm-core/src/main/java/sonia/scm/group/GroupNames.java
@@ -49,7 +49,7 @@ import java.util.Iterator;
  * @author Sebastian Sdorra
  * @since 1.21
  */
-public class GroupNames implements Serializable, Iterable<String>
+public final class GroupNames implements Serializable, Iterable<String>
 {
 
   /** Field description */
diff --git a/scm-core/src/main/java/sonia/scm/security/RepositoryPermission.java b/scm-core/src/main/java/sonia/scm/security/RepositoryPermission.java
index aad7a4f126..375f6579d0 100644
--- a/scm-core/src/main/java/sonia/scm/security/RepositoryPermission.java
+++ b/scm-core/src/main/java/sonia/scm/security/RepositoryPermission.java
@@ -50,7 +50,7 @@ import java.io.Serializable;
  * @author Sebastian Sdorra
  * @since 1.21
  */
-public class RepositoryPermission implements Permission, Serializable
+public final class RepositoryPermission implements Permission, Serializable
 {
 
   /** Field description */