diff --git a/artifactory_cleanup/rules/docker.py b/artifactory_cleanup/rules/docker.py
index 5556bd2..40c54c0 100644
--- a/artifactory_cleanup/rules/docker.py
+++ b/artifactory_cleanup/rules/docker.py
@@ -160,11 +160,6 @@ def get_masks(self):
         # alpine:2.4 => alpine/2.4
         return [mask.replace(":", "/") for mask in self.masks]
 
-    def check(self):
-        for mask in self.masks:
-            if ":" not in mask:
-                raise AttributeError(f"Mask '{mask}' must contain ':' in docker rules")
-
     def aql_add_filter(self, filters):
         rule_list = []
         for mask in self.get_masks():