diff --git a/.github/.OwlBot.lock.yaml b/.github/.OwlBot.lock.yaml
deleted file mode 100644
index c4e82889d..000000000
--- a/.github/.OwlBot.lock.yaml
+++ /dev/null
@@ -1,17 +0,0 @@
-# Copyright 2025 Google LLC
-#
-# Licensed under the Apache License, Version 2.0 (the "License");
-# you may not use this file except in compliance with the License.
-# You may obtain a copy of the License at
-#
-#      http://www.apache.org/licenses/LICENSE-2.0
-#
-# Unless required by applicable law or agreed to in writing, software
-# distributed under the License is distributed on an "AS IS" BASIS,
-# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-# See the License for the specific language governing permissions and
-# limitations under the License.
-docker:
-  image: gcr.io/cloud-devrel-public-resources/owlbot-python:latest
-  digest: sha256:023a21377a2a00008057f99f0118edadc30a19d1636a3fee47189ebec2f3921c
-# created: 2025-03-31T16:51:40.130756953Z
diff --git a/.github/.OwlBot.yaml b/.github/.OwlBot.yaml
deleted file mode 100644
index ed6155aab..000000000
--- a/.github/.OwlBot.yaml
+++ /dev/null
@@ -1,18 +0,0 @@
-# Copyright 2021 Google LLC
-#
-# Licensed under the Apache License, Version 2.0 (the "License");
-# you may not use this file except in compliance with the License.
-# You may obtain a copy of the License at
-#
-#     http://www.apache.org/licenses/LICENSE-2.0
-#
-# Unless required by applicable law or agreed to in writing, software
-# distributed under the License is distributed on an "AS IS" BASIS,
-# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-# See the License for the specific language governing permissions and
-# limitations under the License.
-
-docker:
-  image: gcr.io/cloud-devrel-public-resources/owlbot-python:latest
-
-begin-after-commit-hash: ee56c3493ec6aeb237ff515ecea949710944a20f
diff --git a/.github/release-please.yml b/.github/release-please.yml
deleted file mode 100644
index 466597e5b..000000000
--- a/.github/release-please.yml
+++ /dev/null
@@ -1,2 +0,0 @@
-releaseType: python
-handleGHRelease: true
diff --git a/.github/release-trigger.yml b/.github/release-trigger.yml
deleted file mode 100644
index d4ca94189..000000000
--- a/.github/release-trigger.yml
+++ /dev/null
@@ -1 +0,0 @@
-enabled: true
diff --git a/.librarian/config.yaml b/.librarian/config.yaml
new file mode 100644
index 000000000..111f94dd5
--- /dev/null
+++ b/.librarian/config.yaml
@@ -0,0 +1,6 @@
+global_files_allowlist:
+  # Allow the container to read and write the root `CHANGELOG.md`
+  # file during the `release` step to update the latest client library
+  # versions which are hardcoded in the file.
+  - path: "CHANGELOG.md"
+    permissions: "read-write"
diff --git a/.librarian/state.yaml b/.librarian/state.yaml
new file mode 100644
index 000000000..802ccbf15
--- /dev/null
+++ b/.librarian/state.yaml
@@ -0,0 +1,25 @@
+image: python-librarian-generator:latest
+libraries:
+  - id: google-auth
+    version: 2.42.0
+    last_generated_commit: 102d9f92ac6ed649a61efd9b208e4d1de278e9bb
+    apis: []
+    source_roots:
+      - docs
+      - google
+      - samples
+      - scripts
+      - system_tests
+      - testing
+      - tests
+      - tests_async
+      - .repo-metadata.json
+      - CHANGELOG.md
+      - CONTRIBUTING.rst
+      - LICENSE
+      - MANIFEST.in
+      - noxfile.py
+    preserve_regex:
+      - .*
+    remove_regex: []
+    tag_format: v{version}
diff --git a/CHANGELOG.md b/CHANGELOG.md
index 90299bdf5..6b4ad1ee7 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -4,6 +4,27 @@
 
 [1]: https://pypi.org/project/google-auth/#history
 
+## [2.42.0](https://github.com/googleapis/google-cloud-python/compare/google-auth-v2.41.1...google-auth-v2.42.0) (2025-10-15)
+
+
+### Features
+
+* onboard `google-auth` to librarian  ([4059a5d33a5d5c66776adddbb0eeea373a66dffb](https://github.com/googleapis/google-cloud-python/commit/4059a5d33a5d5c66776adddbb0eeea373a66dffb))
+* Add trust boundary support for external accounts. (#1809) * feat: Add trust boundary support for external accounts.
+* Add trust boundary support to external account authorized users.
+* Fix lint issues
+* Implement additional unit tests for external account authorized user.
+* fix formatting issue
+* Add a unit test with invalid audiance
+* add missing unit tests ([36ecb1d65883477d27faf9c2281fc289659b9903](https://github.com/googleapis/google-cloud-python/commit/36ecb1d65883477d27faf9c2281fc289659b9903))
+
+## [2.41.2](https://github.com/googleapis/google-auth-library-python/compare/v2.41.1...v2.41.2) (2025-10-14)
+
+
+### Bug Fixes
+
+* Testing changes
+
 ## [2.41.1](https://github.com/googleapis/google-auth-library-python/compare/v2.41.0...v2.41.1) (2025-09-30)
 
 
diff --git a/google/auth/__init__.py b/google/auth/__init__.py
index 765bbd705..fc352451a 100644
--- a/google/auth/__init__.py
+++ b/google/auth/__init__.py
@@ -51,3 +51,6 @@ class Python37DeprecationWarning(DeprecationWarning):  # pragma: NO COVER
 
 # Set default logging handler to avoid "No handler found" warnings.
 logging.getLogger(__name__).addHandler(logging.NullHandler())
+
+
+## test change
\ No newline at end of file
diff --git a/google/auth/version.py b/google/auth/version.py
index 6f67e6b34..208942661 100644
--- a/google/auth/version.py
+++ b/google/auth/version.py
@@ -12,4 +12,4 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
-__version__ = "2.41.1"
+__version__ = "2.42.0"