diff --git a/protoplasm/__init__.py b/protoplasm/__init__.py
index 38a5c87..60bef0a 100644
--- a/protoplasm/__init__.py
+++ b/protoplasm/__init__.py
@@ -1,4 +1,4 @@
-__version__ = '5.3.0'
+__version__ = '5.3.1'
 
 __author__ = 'Thordur Matthiasson <thordurm@ccpgames.com>'
 __license__ = 'MIT License'
diff --git a/pyproject.toml b/pyproject.toml
index 2e71e89..4bb4ac5 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -36,7 +36,7 @@ classifiers = [
 
 dependencies = [
     "ccptools >= 1.1, <2",
-    "protobuf >=5.28.2, <6",
+    "protobuf == 5.27.2",
     "grpcio >=1.66.1, <2",
     "grpcio-tools >=1.66.1, <2",
     "googleapis-common-protos >=1.65, <2"