diff --git a/.github/.OwlBot.lock.yaml b/.github/.OwlBot.lock.yaml
index d49860b32e..c1ef6e601d 100644
--- a/.github/.OwlBot.lock.yaml
+++ b/.github/.OwlBot.lock.yaml
@@ -1,4 +1,3 @@
 docker:
-  digest: sha256:457583330eec64daa02aeb7a72a04d33e7be2428f646671ce4045dcbc0191b1e
-  image: gcr.io/repo-automation-bots/owlbot-python:latest  
-
+  image: gcr.io/repo-automation-bots/owlbot-python:latest
+  digest: sha256:9d6a2d613e2c04c07ecdb6c287e3931890f6d30266ab5ee4ee412f748dc98341
diff --git a/.pre-commit-config.yaml b/.pre-commit-config.yaml
index 1bbd787833..4f00c7cffc 100644
--- a/.pre-commit-config.yaml
+++ b/.pre-commit-config.yaml
@@ -26,6 +26,6 @@ repos:
     hooks:
     - id: black
 -   repo: https://gitlab.com/pycqa/flake8
-    rev: 3.9.1
+    rev: 3.9.2
     hooks:
     - id: flake8
diff --git a/docs/conf.py b/docs/conf.py
index cd484b1e23..e2ee78b704 100644
--- a/docs/conf.py
+++ b/docs/conf.py
@@ -363,6 +363,7 @@
     "google.api_core": ("https://googleapis.dev/python/google-api-core/latest/", None,),
     "grpc": ("https://grpc.github.io/grpc/python/", None),
     "proto-plus": ("https://proto-plus-python.readthedocs.io/en/latest/", None),
+    "protobuf": ("https://googleapis.dev/python/protobuf/latest/", None),
 }
 
 
diff --git a/docs/multiprocessing.rst b/docs/multiprocessing.rst
index 1cb29d4ca9..536d17b2ea 100644
--- a/docs/multiprocessing.rst
+++ b/docs/multiprocessing.rst
@@ -1,7 +1,7 @@
 .. note::
 
-   Because this client uses :mod:`grpcio` library, it is safe to
+   Because this client uses :mod:`grpc` library, it is safe to
    share instances across threads. In multiprocessing scenarios, the best
    practice is to create client instances *after* the invocation of
-   :func:`os.fork` by :class:`multiprocessing.Pool` or
+   :func:`os.fork` by :class:`multiprocessing.pool.Pool` or
    :class:`multiprocessing.Process`.
diff --git a/noxfile.py b/noxfile.py
index b46cf43a0f..1c4b22dbda 100644
--- a/noxfile.py
+++ b/noxfile.py
@@ -179,7 +179,7 @@ def docs(session):
     """Build the docs for this library."""
 
     session.install("-e", ".")
-    session.install("sphinx", "alabaster", "recommonmark")
+    session.install("sphinx==4.0.1", "alabaster", "recommonmark")
 
     shutil.rmtree(os.path.join("docs", "_build"), ignore_errors=True)
     session.run(
@@ -200,7 +200,9 @@ def docfx(session):
     """Build the docfx yaml files for this library."""
 
     session.install("-e", ".")
-    session.install("sphinx", "alabaster", "recommonmark", "gcp-sphinx-docfx-yaml")
+    session.install(
+        "sphinx==4.0.1", "alabaster", "recommonmark", "gcp-sphinx-docfx-yaml"
+    )
 
     shutil.rmtree(os.path.join("docs", "_build"), ignore_errors=True)
     session.run(