diff --git a/CHANGELOG.md b/CHANGELOG.md
index e280b1c7e..a88e9e69f 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -11,6 +11,8 @@
 
 ### Bugfix
 
+* fix `generic_adder` not creating new field from type `list`
+
 ## v10.0.3
 ### Bugfix
 * fix loading of configuration inside the `AutoRuleCorpusTester` for `logprep test integration`
diff --git a/doc/source/development/notebooks/processor_examples/generic_adder.ipynb b/doc/source/development/notebooks/processor_examples/generic_adder.ipynb
new file mode 100644
index 000000000..141207e8b
--- /dev/null
+++ b/doc/source/development/notebooks/processor_examples/generic_adder.ipynb
@@ -0,0 +1,199 @@
+{
+ "cells": [
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "# Calculator\n",
+    "\n",
+    "This presentations goal it to introduce the features of the `Calculator` and how to configure it."
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "### The challenge\n",
+    "\n",
+    "I want calculate with field values."
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "from this:"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 24,
+   "metadata": {},
+   "outputs": [],
+   "source": [
+    "document = {\n",
+    "    'message': {\n",
+    "        \"time_in_ms\": \"bla\",\n",
+    "        \"tags\": [\"hello\"]\n",
+    "        }\n",
+    "    }"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "to this:"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 25,
+   "metadata": {},
+   "outputs": [],
+   "source": [
+    "expected = {\n",
+    "    'message': {\n",
+    "        \"time_in_ms\": \"bla\",\n",
+    "        \"tags\": [\"hello\", \"new\"]\n",
+    "        }\n",
+    "    }"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "### Create rule and processor"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "create the rule:"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {},
+   "outputs": [],
+   "source": []
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "create the processor config:"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 26,
+   "metadata": {},
+   "outputs": [],
+   "source": [
+    "processor_config = {\n",
+    "    \"almighty generic adder\":{   \n",
+    "        \"type\": \"generic_adder\",\n",
+    "        \"specific_rules\": [{\"filter\": \"*\", \"generic_adder\": {\"extend_target_list\": True, \"add\": {\"message.tags\": \"New\"}} }],\n",
+    "        \"generic_rules\": [],\n",
+    "        }\n",
+    "    }"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "create the processor with the factory:"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 27,
+   "metadata": {},
+   "outputs": [
+    {
+     "data": {
+      "text/plain": [
+       "generic_adder"
+      ]
+     },
+     "execution_count": 27,
+     "metadata": {},
+     "output_type": "execute_result"
+    }
+   ],
+   "source": [
+    "from unittest import mock\n",
+    "from logprep.factory import Factory\n",
+    "\n",
+    "mock_logger = mock.MagicMock()\n",
+    "calculator = Factory.create(processor_config, mock_logger)\n",
+    "calculator"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "### Process event"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 28,
+   "metadata": {},
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "before: {'message': {'time_in_ms': 'bla', 'tags': ['hello']}}\n",
+      "after: {'message': {'time_in_ms': 'bla', 'tags': ['hello', 'New']}}\n",
+      "False\n"
+     ]
+    }
+   ],
+   "source": [
+    "from copy import deepcopy\n",
+    "mydocument = deepcopy(document)\n",
+    "\n",
+    "\n",
+    "print(f\"before: {mydocument}\")\n",
+    "calculator.process(mydocument)\n",
+    "print(f\"after: {mydocument}\")\n",
+    "print(mydocument == expected)"
+   ]
+  }
+ ],
+ "metadata": {
+  "kernelspec": {
+   "display_name": "Python 3.11.0 ('.venv': venv)",
+   "language": "python",
+   "name": "python3"
+  },
+  "language_info": {
+   "codemirror_mode": {
+    "name": "ipython",
+    "version": 3
+   },
+   "file_extension": ".py",
+   "mimetype": "text/x-python",
+   "name": "python",
+   "nbconvert_exporter": "python",
+   "pygments_lexer": "ipython3",
+   "version": "3.11.7"
+  },
+  "orig_nbformat": 4,
+  "vscode": {
+   "interpreter": {
+    "hash": "586280540a85d3e21edc698fe7b86af2848b9b02644e6c22463da25c40a3f1be"
+   }
+  }
+ },
+ "nbformat": 4,
+ "nbformat_minor": 2
+}
diff --git a/logprep/processor/generic_adder/rule.py b/logprep/processor/generic_adder/rule.py
index e29064352..f49b7e77a 100644
--- a/logprep/processor/generic_adder/rule.py
+++ b/logprep/processor/generic_adder/rule.py
@@ -98,7 +98,7 @@
 
 from attrs import define, field, validators
 
-from logprep.processor.base.rule import Rule, InvalidRuleDefinitionError
+from logprep.processor.base.rule import InvalidRuleDefinitionError, Rule
 from logprep.processor.field_manager.rule import FieldManagerRule
 from logprep.util.getter import GetterFactory
 
@@ -119,7 +119,7 @@ class Config(Rule.Config):
         add: dict = field(
             validator=validators.deep_mapping(
                 key_validator=validators.instance_of(str),
-                value_validator=validators.instance_of((str, bool)),
+                value_validator=validators.instance_of((str, bool, list)),
             ),
             default={},
         )
diff --git a/tests/unit/processor/generic_adder/test_generic_adder.py b/tests/unit/processor/generic_adder/test_generic_adder.py
index 109a0026c..b66f11fdc 100644
--- a/tests/unit/processor/generic_adder/test_generic_adder.py
+++ b/tests/unit/processor/generic_adder/test_generic_adder.py
@@ -282,6 +282,19 @@ class TestGenericAdder(BaseProcessorTestCase):
                 "dotted": {"added": {"field": "yet_another_value"}},
             },
         ),
+        (
+            "Extend list field with 'extend_target_list' enabled",
+            {
+                "filter": "*",
+                "generic_adder": {
+                    "add": {
+                        "some_added_field": ["some value"],
+                    },
+                },
+            },
+            {"extend_generic_test": "Test"},
+            {"extend_generic_test": "Test", "some_added_field": ["some value"]},
+        ),
     ]
 
     failure_test_cases = [  # testcase, rule, event, expected, error_message