diff --git a/src/spdx/model/snippet.py b/src/spdx/model/snippet.py
index fc9fa0353..b88d9d835 100644
--- a/src/spdx/model/snippet.py
+++ b/src/spdx/model/snippet.py
@@ -35,7 +35,7 @@ def __init__(
         license_concluded: Optional[Union[LicenseExpression, SpdxNoAssertion, SpdxNone]] = None,
         license_info_in_snippet: List[Union[LicenseExpression, SpdxNoAssertion, SpdxNone]] = None,
         license_comment: Optional[str] = None,
-        copyright_text: Optional[str] = None,
+        copyright_text: Optional[Union[str, SpdxNoAssertion, SpdxNone]] = None,
         comment: Optional[str] = None,
         name: Optional[str] = None,
         attribution_texts: List[str] = None,