diff --git a/library_generation/postprocess_library.sh b/library_generation/postprocess_library.sh
index 66c0c1a020..c6a5b4020d 100755
--- a/library_generation/postprocess_library.sh
+++ b/library_generation/postprocess_library.sh
@@ -62,7 +62,22 @@ fi
 # we determine the location of the .OwlBot.yaml file by checking if the target
 # folder is a monorepo folder or not
 if [[ "${is_monorepo}" == "true" ]]; then
-  owlbot_yaml_relative_path=".OwlBot.yaml"
+  # the deep-remove-regex and deep-preserve-regex of the .OwlBot.yaml
+  # files in the monorepo libraries assume that `copy-code` is run
+  # from the root of the monorepo. However, we call `copy-code` from inside each
+  # library, so a path like `/java-asset/google-.*/src` will not have
+  # any effect. We solve this by creating a temporary owlbot yaml with
+  # the patched paths.
+  # For example, we convert 
+  # - "/java-asset/google-.*/src"
+  # to
+  # - "/google-.*/src"
+
+  library_name=$(basename "${postprocessing_target}")
+  cat "${postprocessing_target}/.OwlBot.yaml" \
+    | sed "s/- \"\/${library_name}/ - \"/" \
+    > "${postprocessing_target}/.OwlBot.hermetic.yaml"
+  owlbot_yaml_relative_path=".OwlBot.hermetic.yaml"
 else
   owlbot_yaml_relative_path=".github/.OwlBot.yaml"
 fi
@@ -109,6 +124,11 @@ docker run --rm \
   --source-repo="${preprocessed_libraries_binding}" \
   --config-file="${owlbot_yaml_relative_path}"
 
+# clean the custom owlbot yaml
+if [[ "${is_monorepo}" == "true" ]]; then
+  rm "${postprocessing_target}/.OwlBot.hermetic.yaml"
+fi
+
 # we clone the synthtool library and manually build it
 mkdir -p /tmp/synthtool
 pushd /tmp/synthtool