diff --git a/dkist/dataset/loader.py b/dkist/dataset/loader.py
index f4727a95..36a892f7 100644
--- a/dkist/dataset/loader.py
+++ b/dkist/dataset/loader.py
@@ -19,7 +19,7 @@
     from asdf import ValidationError
 
 
-ASDF_FILENAME_PATTERN = r"^(?P<instrument>[A-Z-]+)_L1_(?P<timestamp>\d{8}T\d{6})_(?P<datasetid>[A-Z]+)(?P<suffix>_user_tools|_metadata)?.asdf$"
+ASDF_FILENAME_PATTERN = r"^(?P<instrument>[A-Z-]+)_L1_(?P<timestamp>\d{8}T\d{6})_(?P<datasetid>[A-Z]{5,})(?P<suffix>_user_tools|_metadata)?.asdf$"
 
 
 def asdf_open_memory_mapping_kwarg(memmap: bool) -> dict: