diff --git a/base/src/main/java/de/staropensource/sosengine/base/exceptions/UnexpectedThrowableException.java b/base/src/main/java/de/staropensource/sosengine/base/exceptions/UnexpectedThrowableException.java
index 5b86c1a..f3f465d 100644
--- a/base/src/main/java/de/staropensource/sosengine/base/exceptions/UnexpectedThrowableException.java
+++ b/base/src/main/java/de/staropensource/sosengine/base/exceptions/UnexpectedThrowableException.java
@@ -21,7 +21,6 @@ package de.staropensource.sosengine.base.exceptions;
 
 import lombok.Getter;
 import org.jetbrains.annotations.NotNull;
-import org.jetbrains.annotations.Nullable;
 
 /**
  * Represents an exception caused by some throwable.
@@ -43,7 +42,7 @@ public class UnexpectedThrowableException extends Exception {
      * @return throwable
      * @since v1-alpha1
      */
-    @Nullable
+    @NotNull
     Throwable throwable;
 
     /**