diff --git a/requirements.txt b/requirements.txt
index 9d3d6f6..97afc6d 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -1,6 +1,6 @@
 boto3
 google-api-core>=1.16.0,<1.24.0
-protobuf>=3.6.0,<3.15
+protobuf>=3.6.0,<4.22
 google-api-python-client
 psycopg2cffi-compat
 six