diff --git a/changelogs/fragments/403-sanity.yml b/changelogs/fragments/403-sanity.yml
new file mode 100644
index 0000000..21e2d8a
--- /dev/null
+++ b/changelogs/fragments/403-sanity.yml
@@ -0,0 +1,2 @@
+trivial:
+  - "Fix currently failing sanity tests by properly specifying falsy defaults in module documentation (https://github.com/ansible-collections/ansible.posix/pull/403)."
diff --git a/plugins/modules/acl.py b/plugins/modules/acl.py
index a2e3d6d..353a423 100644
--- a/plugins/modules/acl.py
+++ b/plugins/modules/acl.py
@@ -44,6 +44,7 @@ options:
     description:
     - The actual user or group that the ACL applies to when matching entity types user or group are selected.
     type: str
+    default: ''
   etype:
     description:
     - The entity type of the ACL to apply, see C(setfacl) documentation for more info.
diff --git a/plugins/modules/rhel_rpm_ostree.py b/plugins/modules/rhel_rpm_ostree.py
index e5e8f2b..0976e02 100644
--- a/plugins/modules/rhel_rpm_ostree.py
+++ b/plugins/modules/rhel_rpm_ostree.py
@@ -35,6 +35,7 @@ options:
     aliases: [ pkg ]
     type: list
     elements: str
+    default: []
   state:
     description:
       - Whether to install (C(present) or C(installed), C(latest)), or remove (C(absent) or C(removed)) a package.