diff --git a/requirements.txt b/requirements.txt
index b38497b62..e683aa29e 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -2,7 +2,7 @@ attrs==21.4.0
 absl-py>=1.0.0
 numpy>=1.21.5
 coverage>=4.5,<=6.4.2
-protobuf>=3.20,<4.0
+protobuf>=3.6,<4.0
 mock>=3.0,<=4.0.3
 pytype>=2022.10.26
 portpicker>=1.5.2
diff --git a/vizier/__init__.py b/vizier/__init__.py
index 6e0705017..596f83031 100644
--- a/vizier/__init__.py
+++ b/vizier/__init__.py
@@ -21,4 +21,4 @@
 
 sys.path.append(PROTO_ROOT)
 
-__version__ = "0.0.12"
+__version__ = "0.0.13"