diff --git a/src/Event/Event.php b/src/Event/Event.php
index 248b310b78..fc2511ed11 100644
--- a/src/Event/Event.php
+++ b/src/Event/Event.php
@@ -11,6 +11,8 @@ namespace Friendica\Event;
 
 /**
  * One-way Event to inform listener about something happend.
+ *
+ * @internal
  */
 final class Event implements NamedEvent
 {
diff --git a/src/Event/EventDispatcher.php b/src/Event/EventDispatcher.php
index 6175996bc6..da92a9b76c 100644
--- a/src/Event/EventDispatcher.php
+++ b/src/Event/EventDispatcher.php
@@ -13,6 +13,8 @@ use Symfony\Component\EventDispatcher\EventDispatcher as SymfonyEventDispatcher;
 
 /**
  * Modified Event Dispatcher.
+ *
+ * @internal
  */
 final class EventDispatcher extends SymfonyEventDispatcher
 {
diff --git a/src/Event/HtmlFilterEvent.php b/src/Event/HtmlFilterEvent.php
index d8b7b742b8..0831fd468b 100644
--- a/src/Event/HtmlFilterEvent.php
+++ b/src/Event/HtmlFilterEvent.php
@@ -11,6 +11,8 @@ namespace Friendica\Event;
 
 /**
  * Allow Event listener to modify HTML.
+ *
+ * @internal
  */
 final class HtmlFilterEvent implements NamedEvent
 {
diff --git a/src/Event/NamedEvent.php b/src/Event/NamedEvent.php
index 424649664c..3f94959cf6 100644
--- a/src/Event/NamedEvent.php
+++ b/src/Event/NamedEvent.php
@@ -11,6 +11,8 @@ namespace Friendica\Event;
 
 /**
  * Interface for named events.
+ *
+ * @internal
  */
 interface NamedEvent
 {
diff --git a/src/EventSubscriber/HookEventBridge.php b/src/EventSubscriber/HookEventBridge.php
index b1408caa40..bce4063ef2 100644
--- a/src/EventSubscriber/HookEventBridge.php
+++ b/src/EventSubscriber/HookEventBridge.php
@@ -16,6 +16,8 @@ use Friendica\Event\NamedEvent;
 
 /**
  * Bridge between the EventDispatcher and the Hook class.
+ *
+ * @internal Provides BC
  */
 final class HookEventBridge implements StaticEventSubscriber
 {
diff --git a/src/EventSubscriber/StaticEventSubscriber.php b/src/EventSubscriber/StaticEventSubscriber.php
index 16b60fb66d..4606b4a6cc 100644
--- a/src/EventSubscriber/StaticEventSubscriber.php
+++ b/src/EventSubscriber/StaticEventSubscriber.php
@@ -11,6 +11,8 @@ namespace Friendica\EventSubscriber;
 
 /**
  * Define events that should be reacted to.
+ *
+ * @internal
  */
 interface StaticEventSubscriber
 {