diff --git a/pyproject.toml b/pyproject.toml
index a8006bff..fdb5d013 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -62,7 +62,7 @@ dev-mkdocs = [
 dev-mypy = [
   "mypy == 2.3.1",
   "types-Markdown == 3.10.2.20260712",
-  "types-protobuf == 7.35.1.20260827",
+  "types-protobuf == 7.35.1.20260906",
   # For checking the noxfile, docs/ script, and tests
   "frequenz-client-common[dev-mkdocs,dev-noxfile,dev-pytest]",
 ]