diff --git a/pyproject.toml b/pyproject.toml
index 7dc945f06add54da20ceb7dbeb30f1cbbe8d6b79..eb01770a332f289cc353c78b6cf9d979b643a7f6 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -8,7 +8,7 @@ dynamic = ["version", "dependencies"]
 requires-python = '>=3.6'
 
 license = "BSD-3-Clause"
-license-files = ["LICENSE"]
+license-files = ["LICENSE", "copyrightstamp.txt"]
 readme = {file = "README.rst", content-type = "text/x-rst"}
 description = 'A scikit-learn compatible package for multimodal Classifiers'
 authors = [