diff --git a/library_generation/README.md b/library_generation/README.md
index 1a9e77893f..efb42b2d48 100644
--- a/library_generation/README.md
+++ b/library_generation/README.md
@@ -91,14 +91,22 @@ Use `--grpc_version` to specify the value.
 
 Note that if specified, the version should be compatible with gapic-generator-java.
 
+### gapic_additional_protos (optional)
+Additional protos that pass to the generator.
+The default value is `google/cloud/common_resources.proto`.
+
+Use `--gapic_additional_protos` to specify the value.
+
 ### transport (optional)
-One of GAPIC options passed to the generator. The value is either `grpc` or `grpc+rest`.
+One of GAPIC options passed to the generator.
+The value is either `grpc` or `grpc+rest`.
 The default value is `grpc`.
 
 Use `--transport` to specify the value.
 
 ### rest_numeric_enums (optional)
-One of GAPIC options passed to the generator. The value is either `true` or `false`.
+One of GAPIC options passed to the generator.
+The value is either `true` or `false`.
 The default value is `true`.
 
 Use `--rest_numeric_enums` to specify the value.
@@ -121,6 +129,7 @@ library_generation/generate_library.sh \
 --gapic_generator_version 2.24.0 \
 --protobuf_version 23.2 \
 --grpc_version 1.55.1 \
+--gapic_additional_protos "google/cloud/common_resources.proto google/cloud/location/locations.proto" \
 --transport grpc+rest \
 --rest_numeric_enums true \
 --include_samples true
diff --git a/library_generation/generate_library.sh b/library_generation/generate_library.sh
index 812d1b1359..9863a6170e 100755
--- a/library_generation/generate_library.sh
+++ b/library_generation/generate_library.sh
@@ -29,6 +29,10 @@ case $key in
     grpc_version="$2"
     shift
     ;;
+  --gapic_additional_protos)
+    gapic_additional_protos="$2"
+    shift
+    ;;
   --transport)
     transport="$2"
     shift
@@ -56,7 +60,6 @@ done
 script_dir=$(dirname "$(readlink -f "$0")")
 source "${script_dir}"/utilities.sh
 output_folder="$(get_output_folder)"
-# source utility functions
 
 if [ -z "${protobuf_version}" ]; then
   protobuf_version=$(get_protobuf_version "${gapic_generator_version}")
@@ -66,6 +69,10 @@ if [ -z "${grpc_version}" ]; then
   grpc_version=$(get_grpc_version "${gapic_generator_version}")
 fi
 
+if [ -z "${gapic_additional_protos}" ]; then
+  gapic_additional_protos="google/cloud/common_resources.proto"
+fi
+
 if [ -z "${transport}" ]; then
   transport="grpc"
 fi
@@ -117,7 +124,7 @@ fi
 "--plugin=protoc-gen-java_gapic=${script_dir}/gapic-generator-java-wrapper" \
 "--java_gapic_out=metadata:${destination_path}/java_gapic_srcjar_raw.srcjar.zip" \
 "--java_gapic_opt=$(get_gapic_opts)" \
-${proto_files} $(search_additional_protos)
+${proto_files} ${gapic_additional_protos}
 
 unzip -o -q "${destination_path}/java_gapic_srcjar_raw.srcjar.zip" -d "${destination_path}"
 # Sync'\''d to the output file name in Writer.java.
diff --git a/library_generation/test/generate_library_integration_test.sh b/library_generation/test/generate_library_integration_test.sh
index 7b42402837..96429c6e43 100755
--- a/library_generation/test/generate_library_integration_test.sh
+++ b/library_generation/test/generate_library_integration_test.sh
@@ -68,6 +68,7 @@ grep -v '^ *#' < "${proto_path_list}" | while IFS= read -r line; do
   # parse GAPIC options from proto_path/BUILD.bazel
   pushd "${output_folder}"
   proto_build_file_path="${proto_path}/BUILD.bazel"
+  gapic_additional_protos=$(get_gapic_additional_protos_from_BUILD "${proto_build_file_path}")
   transport=$(get_transport_from_BUILD "${proto_build_file_path}")
   rest_numeric_enums=$(get_rest_numeric_enums_from_BUILD "${proto_build_file_path}")
   include_samples=$(get_include_samples_from_BUILD "${proto_build_file_path}")
@@ -81,6 +82,7 @@ grep -v '^ *#' < "${proto_path_list}" | while IFS= read -r line; do
   --gapic_generator_version "${gapic_generator_version}" \
   --protobuf_version "${protobuf_version}" \
   --grpc_version "${grpc_version}" \
+  --gapic_additional_protos "${gapic_additional_protos}" \
   --transport "${transport}" \
   --rest_numeric_enums "${rest_numeric_enums}" \
   --include_samples "${include_samples}"
diff --git a/library_generation/test/generate_library_unit_tests.sh b/library_generation/test/generate_library_unit_tests.sh
index b945ffffb1..4af6da36ec 100755
--- a/library_generation/test/generate_library_unit_tests.sh
+++ b/library_generation/test/generate_library_unit_tests.sh
@@ -41,40 +41,6 @@ get_protobuf_version_failed_with_invalid_generator_version_test() {
   assertEquals 1 $((res))
 }
 
-search_additional_protos_common_resources_test() {
-  local proto_path="${script_dir}/resources/search_additional_proto/common_resources"
-  local addition_protos
-  addition_protos=$(search_additional_protos)
-  assertEquals "google/cloud/common_resources.proto" "${addition_protos}"
-}
-
-search_additional_protos_iam_test() {
-  local proto_path="${script_dir}/resources/search_additional_protos/iam"
-  local addition_protos
-  addition_protos=$(search_additional_protos)
-  assertEquals \
-  "google/cloud/common_resources.proto google/iam/v1/iam_policy.proto" \
-  "${addition_protos}"
-}
-
-search_additional_protos_location_test() {
-  local proto_path="${script_dir}/resources/search_additional_protos/location"
-  local addition_protos
-  addition_protos=$(search_additional_protos)
-  assertEquals \
-  "google/cloud/common_resources.proto google/cloud/location/locations.proto" \
-  "${addition_protos}"
-}
-
-search_additional_protos_iam_location_test() {
-  local proto_path="${script_dir}/resources/search_additional_protos/iam_location"
-  local addition_protos
-  addition_protos=$(search_additional_protos)
-  assertEquals \
-  "google/cloud/common_resources.proto google/iam/v1/iam_policy.proto google/cloud/location/locations.proto" \
-  "${addition_protos}"
-}
-
 get_gapic_opts_with_rest_test() {
   local proto_path="${script_dir}/resources/gapic_options"
   local transport="grpc"
@@ -227,6 +193,34 @@ generate_library_failed_with_invalid_grpc_version() {
   cleanup "${destination}"
 }
 
+get_gapic_additional_protos_from_BUILD_common_resources_test() {
+  local proto_path="${script_dir}/resources/search_additional_protos/BUILD_common_resources.bazel"
+  local addition_protos
+  addition_protos=$(get_gapic_additional_protos_from_BUILD "${proto_path}")
+  assertEquals "google/cloud/common_resources.proto" "${addition_protos}"
+}
+
+get_gapic_additional_protos_from_BUILD_iam_policy_test() {
+  local proto_path="${script_dir}/resources/search_additional_protos/BUILD_iam_policy.bazel"
+  local addition_protos
+  addition_protos=$(get_gapic_additional_protos_from_BUILD "${proto_path}")
+  assertEquals "google/cloud/common_resources.proto google/iam/v1/iam_policy.proto" "${addition_protos}"
+}
+
+get_gapic_additional_protos_from_BUILD_locations_test() {
+  local proto_path="${script_dir}/resources/search_additional_protos/BUILD_locations.bazel"
+  local addition_protos
+  addition_protos=$(get_gapic_additional_protos_from_BUILD "${proto_path}")
+  assertEquals "google/cloud/common_resources.proto google/cloud/location/locations.proto" "${addition_protos}"
+}
+
+get_gapic_additional_protos_from_BUILD_iam_locations_test() {
+  local proto_path="${script_dir}/resources/search_additional_protos/BUILD_iam_locations.bazel"
+  local addition_protos
+  addition_protos=$(get_gapic_additional_protos_from_BUILD "${proto_path}")
+  assertEquals "google/cloud/common_resources.proto google/iam/v1/iam_policy.proto google/cloud/location/locations.proto" "${addition_protos}"
+}
+
 get_transport_from_BUILD_grpc_rest_test() {
   local build_file="${script_dir}/resources/misc/BUILD_grpc_rest.bazel"
   local transport
@@ -316,10 +310,6 @@ test_list=(
   get_grpc_version_failed_with_invalid_generator_version_test
   get_protobuf_version_succeed_with_valid_generator_version_test
   get_protobuf_version_failed_with_invalid_generator_version_test
-  search_additional_protos_common_resources_test
-  search_additional_protos_iam_test
-  search_additional_protos_location_test
-  search_additional_protos_iam_location_test
   get_gapic_opts_with_rest_test
   get_gapic_opts_without_rest_test
   remove_grpc_version_test
@@ -336,6 +326,10 @@ test_list=(
   generate_library_failed_with_invalid_generator_version
   generate_library_failed_with_invalid_protobuf_version
   generate_library_failed_with_invalid_grpc_version
+  get_gapic_additional_protos_from_BUILD_common_resources_test
+  get_gapic_additional_protos_from_BUILD_iam_policy_test
+  get_gapic_additional_protos_from_BUILD_locations_test
+  get_gapic_additional_protos_from_BUILD_iam_locations_test
   get_transport_from_BUILD_grpc_rest_test
   get_transport_from_BUILD_grpc_test
   get_transport_from_BUILD_rest_test
diff --git a/library_generation/test/resources/search_additional_protos/BUILD_common_resources.bazel b/library_generation/test/resources/search_additional_protos/BUILD_common_resources.bazel
new file mode 100644
index 0000000000..45e3987adb
--- /dev/null
+++ b/library_generation/test/resources/search_additional_protos/BUILD_common_resources.bazel
@@ -0,0 +1,6 @@
+# this file is only used in testing `get_gapic_additional_protos_from_BUILD` in utilities.sh
+
+proto_library_with_info(
+  deps = [
+  ]
+)
\ No newline at end of file
diff --git a/library_generation/test/resources/search_additional_protos/BUILD_iam_locations.bazel b/library_generation/test/resources/search_additional_protos/BUILD_iam_locations.bazel
new file mode 100644
index 0000000000..e8241995e2
--- /dev/null
+++ b/library_generation/test/resources/search_additional_protos/BUILD_iam_locations.bazel
@@ -0,0 +1,8 @@
+# this file is only used in testing `get_gapic_additional_protos_from_BUILD` in utilities.sh
+
+proto_library_with_info(
+  deps = [
+    "//google/iam/v1:iam_policy_proto",
+    "//google/cloud/location:location_proto",
+  ]
+)
\ No newline at end of file
diff --git a/library_generation/test/resources/search_additional_protos/BUILD_iam_policy.bazel b/library_generation/test/resources/search_additional_protos/BUILD_iam_policy.bazel
new file mode 100644
index 0000000000..81064a7eb4
--- /dev/null
+++ b/library_generation/test/resources/search_additional_protos/BUILD_iam_policy.bazel
@@ -0,0 +1,7 @@
+# this file is only used in testing `get_gapic_additional_protos_from_BUILD` in utilities.sh
+
+proto_library_with_info(
+  deps = [
+    "//google/iam/v1:iam_policy_proto",
+  ]
+)
\ No newline at end of file
diff --git a/library_generation/test/resources/search_additional_protos/BUILD_locations.bazel b/library_generation/test/resources/search_additional_protos/BUILD_locations.bazel
new file mode 100644
index 0000000000..07faa4ac95
--- /dev/null
+++ b/library_generation/test/resources/search_additional_protos/BUILD_locations.bazel
@@ -0,0 +1,7 @@
+# this file is only used in testing `get_gapic_additional_protos_from_BUILD` in utilities.sh
+
+proto_library_with_info(
+  deps = [
+    "//google/cloud/location:location_proto",
+  ]
+)
\ No newline at end of file
diff --git a/library_generation/test/resources/search_additional_protos/common_resources/search_additional_protos_common_resources_test.yaml b/library_generation/test/resources/search_additional_protos/common_resources/search_additional_protos_common_resources_test.yaml
deleted file mode 100644
index fc5c8bfca5..0000000000
--- a/library_generation/test/resources/search_additional_protos/common_resources/search_additional_protos_common_resources_test.yaml
+++ /dev/null
@@ -1,10 +0,0 @@
-# this file is only used in testing `search_additional_protos` in utilities.sh
-apis:
-- name: google.monitoring.v3.AlertPolicyService
-- name: google.monitoring.v3.GroupService
-- name: google.monitoring.v3.MetricService
-- name: google.monitoring.v3.NotificationChannelService
-- name: google.monitoring.v3.QueryService
-- name: google.monitoring.v3.ServiceMonitoringService
-- name: google.monitoring.v3.SnoozeService
-- name: google.monitoring.v3.UptimeCheckService
diff --git a/library_generation/test/resources/search_additional_protos/iam/search_additional_protos_iam_test.yaml b/library_generation/test/resources/search_additional_protos/iam/search_additional_protos_iam_test.yaml
deleted file mode 100644
index cc946f1e11..0000000000
--- a/library_generation/test/resources/search_additional_protos/iam/search_additional_protos_iam_test.yaml
+++ /dev/null
@@ -1,6 +0,0 @@
-# this file is only used in testing `search_additional_protos` in utilities.sh
-apis:
-- name: google.iam.v1.IAMPolicy
-- name: google.pubsub.v1.Publisher
-- name: google.pubsub.v1.SchemaService
-- name: google.pubsub.v1.Subscriber
diff --git a/library_generation/test/resources/search_additional_protos/iam_location/search_additional_protos_iam_location_test.yaml b/library_generation/test/resources/search_additional_protos/iam_location/search_additional_protos_iam_location_test.yaml
deleted file mode 100644
index 0789b073e4..0000000000
--- a/library_generation/test/resources/search_additional_protos/iam_location/search_additional_protos_iam_location_test.yaml
+++ /dev/null
@@ -1,6 +0,0 @@
-# this file is only used in testing `search_additional_protos` in utilities.sh
-apis:
-- name: google.cloud.alloydb.v1.AlloyDBAdmin
-- name: google.cloud.location.Locations
-- name: google.iam.v1.IAMPolicy
-- name: google.longrunning.Operations
diff --git a/library_generation/test/resources/search_additional_protos/location/search_additional_protos_location_test.yaml b/library_generation/test/resources/search_additional_protos/location/search_additional_protos_location_test.yaml
deleted file mode 100644
index 73abf4dc7c..0000000000
--- a/library_generation/test/resources/search_additional_protos/location/search_additional_protos_location_test.yaml
+++ /dev/null
@@ -1,5 +0,0 @@
-# this file is only used in testing `search_additional_protos` in utilities.sh
-apis:
-- name: google.cloud.location.Locations
-- name: google.firestore.v1.Firestore
-- name: google.longrunning.Operations
diff --git a/library_generation/utilities.sh b/library_generation/utilities.sh
index 4ccdc42f32..2c90cb1554 100755
--- a/library_generation/utilities.sh
+++ b/library_generation/utilities.sh
@@ -18,12 +18,38 @@ __get_config_from_BUILD() {
   if_match=$5
 
   result="${default}"
-  if grep -A 15 "${rule}" "${build_file}" | grep -q "${pattern}"; then
+  if grep -A 20 "${rule}" "${build_file}" | grep -q "${pattern}"; then
     result="${if_match}"
   fi
   echo "${result}"
 }
 
+__get_iam_policy_from_BUILD() {
+  local build_file=$1
+  local contains_iam_policy
+  contains_iam_policy=$(__get_config_from_BUILD \
+    "${build_file}" \
+    "proto_library_with_info(" \
+    "//google/iam/v1:iam_policy_proto" \
+    "false" \
+    "true"
+  )
+  echo "${contains_iam_policy}"
+}
+
+__get_locations_from_BUILD() {
+  local build_file=$1
+  local contains_locations
+  contains_locations=$(__get_config_from_BUILD \
+    "${build_file}" \
+    "proto_library_with_info(" \
+    "//google/cloud/location:location_proto" \
+    "false" \
+    "true"
+  )
+  echo "${contains_locations}"
+}
+
 # define utility functions
 extract_folder_name() {
   local destination_path=$1
@@ -69,33 +95,6 @@ unzip_src_files() {
   rm -r -f "${destination_path}/${category}-${folder_name}/src/main/java/META-INF"
 }
 
-find_additional_protos_in_yaml() {
-  local pattern=$1
-  local find_result
-  find_result=$(grep --include=\*.yaml -rw "${proto_path}" -e "${pattern}")
-  if [ -n "${find_result}" ]; then
-    echo "${find_result}"
-  fi
-}
-
-# Apart from proto files in proto_path, additional protos are needed in order
-# to generate GAPIC client libraries.
-# In most cases, these protos should be within google/ directory, which is
-# pulled from googleapis as a prerequisite.
-# Search additional protos in .yaml files.
-search_additional_protos() {
-  additional_protos="google/cloud/common_resources.proto" # used by every library
-  iam_policy=$(find_additional_protos_in_yaml "name: '*google.iam.v1.IAMPolicy'*")
-  if [ -n "$iam_policy" ]; then
-    additional_protos="$additional_protos google/iam/v1/iam_policy.proto"
-  fi
-  locations=$(find_additional_protos_in_yaml "name: '*google.cloud.location.Locations'*")
-  if [ -n "${locations}" ]; then
-    additional_protos="$additional_protos google/cloud/location/locations.proto"
-  fi
-  echo "${additional_protos}"
-}
-
 # get gapic options from .yaml and .json files from proto_path.
 get_gapic_opts() {
   local gapic_config
@@ -253,6 +252,23 @@ get_version_from_WORKSPACE() {
   echo "${version}"
 }
 
+# Apart from proto files in proto_path, additional protos are needed in order
+# to generate GAPIC client libraries.
+# In most cases, these protos should be within google/ directory, which is
+# pulled from googleapis as a prerequisite.
+# Get additional protos in BUILD.bazel.
+get_gapic_additional_protos_from_BUILD() {
+  local build_file=$1
+  local gapic_additional_protos="google/cloud/common_resources.proto"
+  if [[ $(__get_iam_policy_from_BUILD "${build_file}") == "true" ]]; then
+    gapic_additional_protos="${gapic_additional_protos} google/iam/v1/iam_policy.proto"
+  fi
+  if [[ $(__get_locations_from_BUILD "${build_file}") == "true" ]]; then
+    gapic_additional_protos="${gapic_additional_protos} google/cloud/location/locations.proto"
+  fi
+  echo "${gapic_additional_protos}"
+}
+
 get_transport_from_BUILD() {
   local build_file=$1
   local transport
diff --git a/showcase/scripts/generate_showcase.sh b/showcase/scripts/generate_showcase.sh
index 6619f5801d..1b25e3ae68 100755
--- a/showcase/scripts/generate_showcase.sh
+++ b/showcase/scripts/generate_showcase.sh
@@ -39,6 +39,7 @@ fi
 
 
 ggj_version=$(get_version_from_versions_txt ../../versions.txt "gapic-generator-java")
+gapic_additional_protos="google/iam/v1/iam_policy.proto google/cloud/location/locations.proto"
 rest_numeric_enums="false"
 transport="grpc+rest"
 include_samples="false"
@@ -49,6 +50,7 @@ bash "${SCRIPT_DIR}/../../library_generation/generate_library.sh" \
   --proto_path "schema/google/showcase/v1beta1" \
   --destination_path "showcase-output" \
   --gapic_generator_version "${ggj_version}" \
+  --gapic_additional_protos "${gapic_additional_protos}" \
   --rest_numeric_enums "${rest_numeric_enums}" \
   --include_samples "${include_samples}" \
   --transport "${transport}"