diff --git a/modules/common/src/main/java/org/dcache/auth/OpScopedPrincipal.java b/modules/common/src/main/java/org/dcache/auth/OpScopedPrincipal.java
index a4a1050012c..aa22341aa2f 100644
--- a/modules/common/src/main/java/org/dcache/auth/OpScopedPrincipal.java
+++ b/modules/common/src/main/java/org/dcache/auth/OpScopedPrincipal.java
@@ -49,6 +49,9 @@ public boolean equals(Object other) {
             return true;
         }
 
+        if (other == null) {
+            return false;
+        }
         return this.getClass().equals(other.getClass())
               && ((Principal) other).getName().equals(name);
     }