diff --git a/.release-please-manifest.json b/.release-please-manifest.json
index a09efe7..87f5de0 100644
--- a/.release-please-manifest.json
+++ b/.release-please-manifest.json
@@ -1,3 +1,3 @@
 {
-  ".": "1.12.0"
+  ".": "1.12.1"
 }
diff --git a/CHANGELOG.md b/CHANGELOG.md
index 0c07bf8..8e4d37c 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,5 +1,11 @@
 # Release History
 
+### 1.12.1 (2024-12-17)
+
+#### Bug Fixes
+
+* Restored previous behavior where the apply! method returns the auth header ([#506](https://github.com/googleapis/google-auth-library-ruby/issues/506)) 
+
 ### 1.12.0 (2024-12-05)
 
 #### Features
diff --git a/lib/googleauth/version.rb b/lib/googleauth/version.rb
index ecc7eff..1f61510 100644
--- a/lib/googleauth/version.rb
+++ b/lib/googleauth/version.rb
@@ -16,6 +16,6 @@ module Google
   # Module Auth provides classes that provide Google-specific authorization
   # used to access Google APIs.
   module Auth
-    VERSION = "1.12.0".freeze
+    VERSION = "1.12.1".freeze
   end
 end