diff --git a/src/marshmallow/schema.py b/src/marshmallow/schema.py
index cde8c080f..4342c6097 100644
--- a/src/marshmallow/schema.py
+++ b/src/marshmallow/schema.py
@@ -374,7 +374,7 @@ def __init__(
         context: dict | None = None,
         load_only: types.StrSequenceOrSet = (),
         dump_only: types.StrSequenceOrSet = (),
-        partial: bool | types.StrSequenceOrSet = False,
+        partial: bool | types.StrSequenceOrSet | None = None,
         unknown: str | None = None,
     ):
         # Raise error if only or exclude is passed as string, not list of strings
@@ -590,7 +590,7 @@ def _deserialize(
         *,
         error_store: ErrorStore,
         many: bool = False,
-        partial=False,
+        partial=None,
         unknown=RAISE,
         index=None,
     ) -> _T | list[_T]:
@@ -1089,7 +1089,7 @@ def _invoke_load_processors(
         *,
         many: bool,
         original_data,
-        partial: bool | types.StrSequenceOrSet,
+        partial: bool | types.StrSequenceOrSet | None,
     ):
         # This has to invert the order of the dump processors, so run the pass_many
         # processors first.
@@ -1166,7 +1166,7 @@ def _invoke_schema_validators(
         data,
         original_data,
         many: bool,
-        partial: bool | types.StrSequenceOrSet,
+        partial: bool | types.StrSequenceOrSet | None,
         field_errors: bool = False,
     ):
         for attr_name in self._hooks[(VALIDATES_SCHEMA, pass_many)]: