diff --git a/capa/main.py b/capa/main.py
index 5a835c79..fe6f78b2 100644
--- a/capa/main.py
+++ b/capa/main.py
@@ -1087,7 +1087,6 @@ def compute_static_layout(rules, extractor: StaticFeatureExtractor, capabilities
     otherwise, we may pollute the json document with
     a large amount of un-referenced data.
     """
-    assert isinstance(extractor, StaticFeatureExtractor)
     functions_by_bb: Dict[Address, Address] = {}
     bbs_by_function: Dict[Address, List[Address]] = {}
     for f in extractor.get_functions():