diff --git a/src/wp-includes/rest-api.php b/src/wp-includes/rest-api.php
index 9a615419b9..cc326eb0da 100644
--- a/src/wp-includes/rest-api.php
+++ b/src/wp-includes/rest-api.php
@@ -2151,7 +2151,7 @@ function rest_validate_value_from_schema( $value, $args, $param = '' ) {
 				break;
 
 			case 'date-time':
-				if ( ! rest_parse_date( $value ) ) {
+				if ( false === rest_parse_date( $value ) ) {
 					return new WP_Error( 'rest_invalid_date', __( 'Invalid date.' ) );
 				}
 				break;