diff --git a/CHANGELOG.md b/CHANGELOG.md
index 69c0b67..86d191d 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,5 +1,12 @@
 # Changelog
 
+## [1.12.4](https://github.com/googleapis/python-os-config/compare/v1.12.3...v1.12.4) (2022-10-07)
+
+
+### Bug Fixes
+
+* **deps:** Allow protobuf 3.19.5 ([#245](https://github.com/googleapis/python-os-config/issues/245)) ([adeb2d1](https://github.com/googleapis/python-os-config/commit/adeb2d1bc30f88c032a1079f9469046e6ca5b5f1))
+
 ## [1.12.3](https://github.com/googleapis/python-os-config/compare/v1.12.2...v1.12.3) (2022-09-29)
 
 
diff --git a/setup.py b/setup.py
index ff3d685..9574a22 100644
--- a/setup.py
+++ b/setup.py
@@ -24,7 +24,7 @@
 
 name = "google-cloud-os-config"
 description = "Google Cloud OS Config API client library"
-version = "1.12.3"
+version = "1.12.4"
 # Should be one of:
 # 'Development Status :: 3 - Alpha'
 # 'Development Status :: 4 - Beta'
@@ -33,7 +33,7 @@
 dependencies = [
     "google-api-core[grpc] >= 1.32.0, <3.0.0dev,!=2.0.*,!=2.1.*,!=2.2.*,!=2.3.*,!=2.4.*,!=2.5.*,!=2.6.*,!=2.7.*",
     "proto-plus >= 1.22.0, <2.0.0dev",
-    "protobuf >= 3.20.2, <5.0.0dev",
+    "protobuf>=3.19.5,<5.0.0dev,!=3.20.0,!=3.20.1,!=4.21.0,!=4.21.1,!=4.21.2,!=4.21.3,!=4.21.4,!=4.21.5",
 ]
 extras = {}
 
diff --git a/testing/constraints-3.7.txt b/testing/constraints-3.7.txt
index 260e08b..5dcaa6f 100644
--- a/testing/constraints-3.7.txt
+++ b/testing/constraints-3.7.txt
@@ -7,4 +7,4 @@
 # Then this file should have foo==1.14.0
 google-api-core==1.32.0
 proto-plus==1.22.0
-protobuf==3.20.2
+protobuf==3.19.5