diff --git a/peps/pep-0751.rst b/peps/pep-0751.rst
index 7ec44af1b5e..c3d29f453a5 100644
--- a/peps/pep-0751.rst
+++ b/peps/pep-0751.rst
@@ -499,7 +499,7 @@ See ``groups.requirements.marker``.
 ``packages.sdist.url``
 ''''''''''''''''''''''
 
-- Required if ``path`` is not set
+- Optional; mutually-exclusive with ``path``
 - String
 - The URL to the file.
 
@@ -507,7 +507,7 @@ See ``groups.requirements.marker``.
 ``packages.sdist.path``
 '''''''''''''''''''''''
 
-- Required if ``url`` is not set
+- Optional; mutually-exclusive with ``url``
 - String
 - A path to the file, which may be absolute or relative.
 - If the path is relative it MUST be relative to the lock file.