diff --git a/src/poetry/core/masonry/builders/builder.py b/src/poetry/core/masonry/builders/builder.py
index e0b33eead..b8fb80cbb 100644
--- a/src/poetry/core/masonry/builders/builder.py
+++ b/src/poetry/core/masonry/builders/builder.py
@@ -170,11 +170,7 @@ def find_files_to_add(self, exclude_build: bool = True) -> Set["BuildIncludeFile
                 if "__pycache__" in str(file):
                     continue
 
-                if (
-                    isinstance(include, PackageInclude)
-                    and include.source
-                    and self.format == "wheel"
-                ):
+                if isinstance(include, PackageInclude) and include.source:
                     source_root = include.base
                 else:
                     source_root = self._path