diff --git a/src/Psalm/Internal/Provider/ReturnTypeProvider/ArrayMergeReturnTypeProvider.php b/src/Psalm/Internal/Provider/ReturnTypeProvider/ArrayMergeReturnTypeProvider.php
index 05efc3c4e..12a985462 100644
--- a/src/Psalm/Internal/Provider/ReturnTypeProvider/ArrayMergeReturnTypeProvider.php
+++ b/src/Psalm/Internal/Provider/ReturnTypeProvider/ArrayMergeReturnTypeProvider.php
@@ -130,10 +130,18 @@ class ArrayMergeReturnTypeProvider implements FunctionReturnTypeProviderInterfac
                                 $class_strings[$key] = true;
                             }
 
-                            if (!isset($generic_properties[$key]) || !$type->possibly_undefined) {
+                            if (!isset($generic_properties[$key]) || (
+                                !$type->possibly_undefined
+                                    && !$unpacking_possibly_empty
+                                    && $is_replace
+                            )) {
+                                if ($unpacking_possibly_empty) {
+                                    $type = $type->setPossiblyUndefined(true);
+                                }
                                 $generic_properties[$key] = $type;
                             } else {
-                                $was_possibly_undefined = $generic_properties[$key]->possibly_undefined;
+                                $was_possibly_undefined = $generic_properties[$key]->possibly_undefined
+                                    || $unpacking_possibly_empty;
 
                                 $generic_properties[$key] = Type::combineUnionTypes(
                                     $generic_properties[$key],
@@ -147,7 +155,7 @@ class ArrayMergeReturnTypeProvider implements FunctionReturnTypeProviderInterfac
                             }
                         }
 
-                        if (!$unpacked_type_part->is_list && !$unpacking_possibly_empty) {
+                        if (!$unpacked_type_part->is_list) {
                             $all_nonempty_lists = false;
                         }
 
diff --git a/tests/ArrayFunctionCallTest.php b/tests/ArrayFunctionCallTest.php
index 369b6aae5..3189266a0 100644
--- a/tests/ArrayFunctionCallTest.php
+++ b/tests/ArrayFunctionCallTest.php
@@ -211,6 +211,24 @@ class ArrayFunctionCallTest extends TestCase
                 'ignored_issues' => [],
                 'php_version' => '8.0',
             ],
+            'arrayMergeListOfShapes' => [
+                'code' => '<?php
+
+                    /** @var list<array{a: int}> */
+                    $a = [];
+
+                    $b = array_merge(...$a);
+
+                    /** @var non-empty-list<array{a: int}> */
+                    $c = [];
+
+                    $d = array_merge(...$c);
+                ',
+                'assertions' => [
+                    '$b' => 'array{a?: int}',
+                    '$d' => 'array{a: int}',
+                ]
+            ],
             'arrayMergeIntArrays' => [
                 'code' => '<?php
                     $d = array_merge(["a", "b", "c", "d"], [1, 2, 3]);',