diff --git a/pyproject.toml b/pyproject.toml
index dadbc77d..54155eaf 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -229,6 +229,7 @@ convention = 'google'
 #
 # Find all (sub-)modules of the Python package
 [tool.setuptools.packages.find]
+include = ['audformat*']
 
 # ----- setuptools_scm ----------------------------------------------------
 #