diff --git a/internal/platform/implementation/BUILD b/internal/platform/implementation/BUILD
index b08b4040..e880aa31 100644
--- a/internal/platform/implementation/BUILD
+++ b/internal/platform/implementation/BUILD
@@ -76,8 +76,8 @@ cc_library(
         "//internal/platform:base",
         "//internal/platform:cancellation_flag",
         "//internal/platform:uuid",
+        "//internal/proto:credential_cc_proto",
         "//presence:credential",
-        "//presence/proto:credential_cc_proto",
         "@com_google_absl//absl/container:flat_hash_map",
         "@com_google_absl//absl/strings",
     ],
diff --git a/internal/platform/implementation/credential_storage.h b/internal/platform/implementation/credential_storage.h
index a9362c52..836eae33 100644
--- a/internal/platform/implementation/credential_storage.h
+++ b/internal/platform/implementation/credential_storage.h
@@ -21,25 +21,26 @@
 #include <vector>
 
 #include "internal/platform/exception.h"
+#include "internal/proto/credential.pb.h"
 #include "presence/presence_identity.h"
-#include "presence/proto/credential.pb.h"
 
 namespace location {
 namespace nearby {
 namespace api {
 
-using ::nearby::presence::PresenceIdentity;
-using ::nearby::presence::proto::PrivateCredential;
-using ::nearby::presence::proto::PublicCredential;
+using ::nearby::internal::IdentityType;
+using ::nearby::internal::PrivateCredential;
+using ::nearby::internal::PublicCredential;
 
 enum class CredentialOperationStatus {
-  kFailed = 0,
-  kSucceeded = 1,
+  kUnknown = 0,
+  kFailed = 1,
+  kSucceeded = 2,
 };
 
 struct CredentialSelector {
   std::string account_name;
-  PresenceIdentity::IdentityType identity_type;
+  IdentityType identity_type;
 };
 
 enum PublicCredentialType {
diff --git a/presence/proto/BUILD b/internal/proto/BUILD
similarity index 100%
rename from presence/proto/BUILD
rename to internal/proto/BUILD
diff --git a/presence/proto/credential.proto b/internal/proto/credential.proto
similarity index 97%
rename from presence/proto/credential.proto
rename to internal/proto/credential.proto
index 5af8efae..dd4b2570 100644
--- a/presence/proto/credential.proto
+++ b/internal/proto/credential.proto
@@ -1,8 +1,8 @@
 syntax = "proto2";
 
-package nearby.presence.proto;
+package nearby.internal;
 
-import "presence/proto/device_metadata.proto";
+import "internal/proto/device_metadata.proto";
 
 option java_package = "com.google.nearby.presence";
 
diff --git a/presence/proto/device_metadata.proto b/internal/proto/device_metadata.proto
similarity index 96%
rename from presence/proto/device_metadata.proto
rename to internal/proto/device_metadata.proto
index 7f081682..d8ceb28c 100644
--- a/presence/proto/device_metadata.proto
+++ b/internal/proto/device_metadata.proto
@@ -1,6 +1,6 @@
 syntax = "proto2";
 
-package nearby.presence.proto;
+package nearby.internal;
 
 // A proto to store the local device's metadata.
 message DeviceMetadata {
diff --git a/presence/BUILD b/presence/BUILD
index 5f0eb2fa..3c7dcaca 100644
--- a/presence/BUILD
+++ b/presence/BUILD
@@ -61,7 +61,7 @@ cc_library(
         ":credential",
         "//net/proto2/util/public:differencer",
         "//internal/platform:base",
-        "//presence/proto:credential_cc_proto",
+        "//internal/proto:credential_cc_proto",
         "@com_google_absl//absl/strings",
         "@com_google_glog//:glog",
     ],
@@ -97,6 +97,7 @@ cc_test(
     deps = [
         ":credential",
         ":types",
+        "//internal/proto:credential_cc_proto",
         "@com_github_protobuf_matchers//protobuf-matchers",
         "@com_google_googletest//:gtest_main",
     ],
@@ -114,7 +115,7 @@ cc_test(
         ":credential",
         "//internal/platform:uuid",
         "//internal/platform/implementation/g3",  # build_cleaner: keep
-        "//presence/proto:credential_cc_proto",
+        "//internal/proto:credential_cc_proto",
         "@com_github_protobuf_matchers//protobuf-matchers",
         "@com_google_googletest//:gtest_main",
     ],
diff --git a/presence/credential_test.cc b/presence/credential_test.cc
index b0715d3a..cacd193c 100644
--- a/presence/credential_test.cc
+++ b/presence/credential_test.cc
@@ -19,15 +19,17 @@
 #include "protobuf-matchers/protocol-buffer-matchers.h"
 #include "gtest/gtest.h"
 #include "internal/platform/uuid.h"
-#include "presence/proto/credential.pb.h"
+#include "internal/proto/credential.pb.h"
 
 namespace nearby {
 namespace presence {
 namespace {
-using ::nearby::presence::proto::PrivateCredential;
-using ::nearby::presence::proto::PublicCredential;
-using ::nearby::presence::proto::IdentityType::IDENTITY_TYPE_PROVISIONED;
-using ::nearby::presence::proto::IdentityType::IDENTITY_TYPE_PUBLIC;
+using ::nearby::internal::DeviceMetadata;
+using ::nearby::internal::PrivateCredential;
+using ::nearby::internal::PublicCredential;
+using ::nearby::internal::IdentityType::IDENTITY_TYPE_PROVISIONED;
+using ::nearby::internal::IdentityType::IDENTITY_TYPE_PUBLIC;
+
 using ::protobuf_matchers::EqualsProto;
 
 TEST(CredentialsTest, NoDefaultConstructor) {
@@ -61,7 +63,7 @@ TEST(CredentialsTest, CopyPrivateCredential) {
   auto salts = pc1.mutable_consumed_salts();
   salts->insert(std::pair<int32, bool>(15, true));
   pc1.mutable_device_metadata()->set_device_name("Android Phone");
-  pc1.mutable_device_metadata()->set_device_type(proto::DeviceMetadata::PHONE);
+  pc1.mutable_device_metadata()->set_device_type(DeviceMetadata::PHONE);
   PrivateCredential pc1_copy = {pc1};
   EXPECT_THAT(pc1, EqualsProto(pc1_copy));
 }
diff --git a/presence/implementation/BUILD b/presence/implementation/BUILD
index 47c96c69..0e664b8e 100644
--- a/presence/implementation/BUILD
+++ b/presence/implementation/BUILD
@@ -48,10 +48,10 @@ cc_library(
         "//internal/platform:uuid",
         "//internal/platform/implementation:comm",
         "//internal/platform/implementation:types",
+        "//internal/proto:credential_cc_proto",
         "//presence:credential",
         "//presence:types",
         "//presence/implementation/mediums",
-        "//presence/proto:credential_cc_proto",
         "//third_party/tink/cc/subtle",
         "@boringssl//:crypto",
         "@com_google_absl//absl/status",
@@ -150,9 +150,9 @@ cc_test(
     deps = [
         ":internal",
         "//net/proto2/contrib/parse_proto:testing",
-        "//internal/crypto",
         "//internal/platform/implementation:types",
         "//internal/platform/implementation/g3",  # build_cleaner: keep
+        "//internal/proto:credential_cc_proto",
         "@com_github_protobuf_matchers//protobuf-matchers",
         "@com_google_googletest//:gtest_main",
     ],
diff --git a/presence/implementation/advertisement_factory.cc b/presence/implementation/advertisement_factory.cc
index b8e520de..b4448535 100644
--- a/presence/implementation/advertisement_factory.cc
+++ b/presence/implementation/advertisement_factory.cc
@@ -21,11 +21,14 @@
 #include "absl/types/variant.h"
 #include "internal/platform/logging.h"
 #include "internal/platform/uuid.h"
+#include "internal/proto/credential.pb.h"
 #include "presence/data_element.h"
 
 namespace nearby {
 namespace presence {
 
+using ::nearby::internal::IdentityType;
+
 constexpr uint8_t kBaseVersion = 0;
 constexpr location::nearby::Uuid kServiceData(0xFCF1ULL << 32, 0);
 
@@ -56,15 +59,16 @@ absl::Status AppendDataElement(unsigned data_type,
   return absl::OkStatus();
 }
 
-uint8_t GetIdentityFieldType(PresenceIdentity::IdentityType type) {
+uint8_t GetIdentityFieldType(IdentityType type) {
   switch (type) {
-    case PresenceIdentity::IdentityType::kPrivate:
+    case IdentityType::IDENTITY_TYPE_PRIVATE:
       return DataElement::kPrivateIdentityFieldType;
-    case PresenceIdentity::IdentityType::kTrusted:
+    case IdentityType::IDENTITY_TYPE_TRUSTED:
       return DataElement::kTrustedIdentityFieldType;
-    case PresenceIdentity::IdentityType::kPublic:
+    case IdentityType::IDENTITY_TYPE_PUBLIC:
       return DataElement::kPublicIdentityFieldType;
-    case PresenceIdentity::IdentityType::kProvisioned:  // fall-through
+    case IdentityType::IDENTITY_TYPE_PROVISIONED:
+      ABSL_FALLTHROUGH_INTENDED;
     default:
       return DataElement::kProvisionedIdentityFieldType;
   }
@@ -101,8 +105,7 @@ AdvertisementFactory::CreateBaseNpAdvertisement(
   if (!identity.ok()) {
     return identity.status();
   }
-  uint8_t identity_type =
-      GetIdentityFieldType(presence.identity.GetIdentityType());
+  uint8_t identity_type = GetIdentityFieldType(presence.identity);
   result = AppendDataElement(identity_type, *identity, payload);
   if (!result.ok()) {
     return result;
diff --git a/presence/implementation/advertisement_factory.h b/presence/implementation/advertisement_factory.h
index 43922c4f..69025277 100644
--- a/presence/implementation/advertisement_factory.h
+++ b/presence/implementation/advertisement_factory.h
@@ -22,7 +22,6 @@
 #include "internal/platform/implementation/ble_v2.h"
 #include "presence/implementation/base_broadcast_request.h"
 #include "presence/implementation/credential_manager.h"
-#include "presence/presence_identity.h"
 
 namespace nearby {
 namespace presence {
diff --git a/presence/implementation/advertisement_factory_test.cc b/presence/implementation/advertisement_factory_test.cc
index 1e142f3a..46a656e6 100644
--- a/presence/implementation/advertisement_factory_test.cc
+++ b/presence/implementation/advertisement_factory_test.cc
@@ -31,6 +31,7 @@ namespace presence {
 
 namespace {
 
+using ::nearby::internal::IdentityType;
 using ::testing::NiceMock;
 using ::testing::Return;
 using ::testing::status::StatusIs;
@@ -38,9 +39,9 @@ using ::testing::status::StatusIs;
 class MockCredentialManager : public CredentialManagerImpl {
  public:
   MOCK_METHOD(absl::StatusOr<std::string>, GetBaseEncryptedMetadataKey,
-              (const PresenceIdentity& identity), (override));
+              (const IdentityType& identity), (override));
   MOCK_METHOD(absl::StatusOr<std::string>, EncryptDataElements,
-              (const PresenceIdentity& identity, absl::string_view salt,
+              (const IdentityType& identity, absl::string_view salt,
                absl::string_view data_elements),
               (override));
 };
@@ -48,21 +49,21 @@ class MockCredentialManager : public CredentialManagerImpl {
 TEST(AdvertisementFactory, CreateAdvertisementFromPrivateIdentity) {
   std::string salt = "AB";
   NiceMock<MockCredentialManager> credential_manager;
-  PresenceIdentity identity;
+  constexpr IdentityType kIdentity = IdentityType::IDENTITY_TYPE_PRIVATE;
   std::vector<DataElement> data_elements;
   data_elements.emplace_back(DataElement::kActionFieldType,
                              action::kActiveUnlockAction);
   Action action = ActionFactory::CreateAction(data_elements);
   BaseBroadcastRequest request =
-      BaseBroadcastRequest(BasePresenceRequestBuilder(identity)
+      BaseBroadcastRequest(BasePresenceRequestBuilder(kIdentity)
                                .SetSalt(salt)
                                .SetTxPower(5)
                                .SetAction(action));
-  EXPECT_CALL(credential_manager, GetBaseEncryptedMetadataKey(identity))
+  EXPECT_CALL(credential_manager, GetBaseEncryptedMetadataKey(kIdentity))
       .WillOnce(Return(absl::HexStringToBytes("1011121314151617181920212223")));
-  EXPECT_CALL(
-      credential_manager,
-      EncryptDataElements(identity, salt, absl::HexStringToBytes("1505260080")))
+  EXPECT_CALL(credential_manager,
+              EncryptDataElements(kIdentity, salt,
+                                  absl::HexStringToBytes("1505260080")))
       .WillOnce(Return(absl::HexStringToBytes("5051525354")));
 
   AdvertisementFactory factory(&credential_manager);
@@ -82,17 +83,17 @@ TEST(AdvertisementFactory, CreateAdvertisementFromPrivateIdentity) {
 
 TEST(AdvertisementFactory, CreateAdvertisementFailsWhenCredentialManagerFails) {
   NiceMock<MockCredentialManager> credential_manager;
-  PresenceIdentity identity;
+  constexpr IdentityType kIdentity = internal::IDENTITY_TYPE_PRIVATE;
   std::vector<DataElement> data_elements;
   data_elements.emplace_back(DataElement::kActionFieldType,
                              action::kActiveUnlockAction);
   Action action = ActionFactory::CreateAction(data_elements);
   BaseBroadcastRequest request =
-      BaseBroadcastRequest(BasePresenceRequestBuilder(identity)
+      BaseBroadcastRequest(BasePresenceRequestBuilder(kIdentity)
                                .SetSalt("AB")
                                .SetTxPower(5)
                                .SetAction(action));
-  EXPECT_CALL(credential_manager, GetBaseEncryptedMetadataKey(identity))
+  EXPECT_CALL(credential_manager, GetBaseEncryptedMetadataKey(kIdentity))
       .WillOnce(Return(absl::UnimplementedError(
           "GetBaseEncryptedMetadataKey not implemented")));
 
diff --git a/presence/implementation/base_broadcast_request.h b/presence/implementation/base_broadcast_request.h
index b1f44315..42f4fc9e 100644
--- a/presence/implementation/base_broadcast_request.h
+++ b/presence/implementation/base_broadcast_request.h
@@ -21,7 +21,7 @@
 
 #include "absl/strings/string_view.h"
 #include "absl/types/variant.h"
-#include "presence/presence_identity.h"
+#include "internal/proto/credential.pb.h"
 
 namespace nearby {
 namespace presence {
@@ -36,7 +36,7 @@ struct Action {
 /** Defines a Nearby Presence broadcast request */
 struct BaseBroadcastRequest {
   struct BasePresence {
-    PresenceIdentity identity;
+    nearby::internal::IdentityType identity;
     Action action;
   };
   struct BaseFastPair {
@@ -61,7 +61,8 @@ struct BaseBroadcastRequest {
 /** Builds a brodacast request variant with NP identity for BLE 4.2 */
 class BasePresenceRequestBuilder {
  public:
-  explicit BasePresenceRequestBuilder(const PresenceIdentity& identity)
+  explicit BasePresenceRequestBuilder(
+      const nearby::internal::IdentityType& identity)
       : identity_(identity) {}
   BasePresenceRequestBuilder& SetSalt(absl::string_view salt);
   BasePresenceRequestBuilder& SetTxPower(int8_t tx_power);
@@ -70,7 +71,7 @@ class BasePresenceRequestBuilder {
   explicit operator BaseBroadcastRequest() const;
 
  private:
-  PresenceIdentity identity_;
+  nearby::internal::IdentityType identity_;
   std::string salt_;
   int8_t tx_power_ = kUnspecifiedTxPower;
   Action action_;
diff --git a/presence/implementation/base_broadcast_request_test.cc b/presence/implementation/base_broadcast_request_test.cc
index 3444350a..6f4ebf12 100644
--- a/presence/implementation/base_broadcast_request_test.cc
+++ b/presence/implementation/base_broadcast_request_test.cc
@@ -24,7 +24,7 @@ namespace presence {
 namespace {
 
 TEST(BroadcastRequestTest, CreateBasePresenceRequest) {
-  PresenceIdentity identity;
+  nearby::internal::IdentityType identity;
   constexpr int8_t kTxPower = -13;
 
   BaseBroadcastRequest request = BaseBroadcastRequest(
diff --git a/presence/implementation/credential_manager.h b/presence/implementation/credential_manager.h
index 869f728d..0825e85b 100644
--- a/presence/implementation/credential_manager.h
+++ b/presence/implementation/credential_manager.h
@@ -22,15 +22,14 @@
 #include "absl/status/statusor.h"
 #include "absl/strings/string_view.h"
 #include "internal/platform/implementation/credential_storage.h"
+#include "internal/proto/credential.pb.h"
 #include "presence/presence_identity.h"
-#include "presence/proto/credential.pb.h"
 
 namespace nearby {
 namespace presence {
-using ::nearby::presence::PresenceIdentity;
 
 struct GenerateCredentialsCallback {
-  std::function<void(std::vector<proto::PublicCredential>)>
+  std::function<void(std::vector<nearby::internal::PublicCredential>)>
       credentials_generated_cb;
 };
 
@@ -56,15 +55,15 @@ class CredentialManager {
   // The user’s own public credentials won’t be saved on local credential
   // storage.
   virtual void GenerateCredentials(
-      proto::DeviceMetadata device_metadata,
-      std::vector<proto::IdentityType> identity_types,
+      nearby::internal::DeviceMetadata device_metadata,
+      std::vector<nearby::internal::IdentityType> identity_types,
       int credential_life_cycle_days, int contiguous_copy_of_credentials,
       GenerateCredentialsCallback credentials_generated_cb) = 0;
 
   // Update remote public credentials.
   virtual void UpdateRemotePublicCredentials(
       std::string account_name,
-      std::vector<proto::PublicCredential> remote_public_creds,
+      std::vector<nearby::internal::PublicCredential> remote_public_creds,
       UpdateRemotePublicCredentialsCallback credentials_updated_cb) = 0;
 
   // Used to fetch private creds when broadcasting.
@@ -93,12 +92,12 @@ class CredentialManager {
   // Returns encrypted metadata key associated with `identity` for Base NP
   // advertisement.
   virtual absl::StatusOr<std::string> GetBaseEncryptedMetadataKey(
-      const PresenceIdentity& identity) = 0;
+      const nearby::internal::IdentityType& identity) = 0;
 
   // Encrypts `data_elements` using certificate associated with `identity` and
   // `salt`.
   virtual absl::StatusOr<std::string> EncryptDataElements(
-      const PresenceIdentity& identity, absl::string_view salt,
+      const nearby::internal::IdentityType& identity, absl::string_view salt,
       absl::string_view data_elements) = 0;
 };
 
diff --git a/presence/implementation/credential_manager_impl.cc b/presence/implementation/credential_manager_impl.cc
index 36250d13..62ebb835 100644
--- a/presence/implementation/credential_manager_impl.cc
+++ b/presence/implementation/credential_manager_impl.cc
@@ -32,8 +32,10 @@ namespace presence {
 namespace {
 using ::location::nearby::Base64Utils;
 using ::location::nearby::Crypto;
-using ::nearby::presence::proto::PrivateCredential;
-using ::nearby::presence::proto::PublicCredential;
+using ::nearby::internal::DeviceMetadata;
+using ::nearby::internal::IdentityType;
+using ::nearby::internal::PrivateCredential;
+using ::nearby::internal::PublicCredential;
 
 // Key to retrieve local device's Private/Public Key Credentials from key store.
 constexpr char kPairedKeyAliasPrefix[] = "nearby_presence_paired_key_alias_";
@@ -41,8 +43,7 @@ constexpr char kPairedKeyAliasPrefix[] = "nearby_presence_paired_key_alias_";
 }  // namespace
 
 void CredentialManagerImpl::GenerateCredentials(
-    proto::DeviceMetadata device_metadata,
-    std::vector<proto::IdentityType> identity_types,
+    DeviceMetadata device_metadata, std::vector<IdentityType> identity_types,
     int credential_life_cycle_days, int contiguous_copy_of_credentials,
     GenerateCredentialsCallback credentials_generated_cb) {
   std::vector<PublicCredential> public_credentials;
@@ -71,9 +72,10 @@ void CredentialManagerImpl::GenerateCredentials(
 }
 
 std::pair<std::unique_ptr<PrivateCredential>, std::unique_ptr<PublicCredential>>
-CredentialManagerImpl::CreatePrivateCredential(
-    proto::DeviceMetadata device_metadata, proto::IdentityType identity_type,
-    uint64_t start_time_ms, uint64_t end_time_ms) {
+CredentialManagerImpl::CreatePrivateCredential(DeviceMetadata device_metadata,
+                                               IdentityType identity_type,
+                                               uint64_t start_time_ms,
+                                               uint64_t end_time_ms) {
   auto private_credential_ptr = std::make_unique<PrivateCredential>();
   private_credential_ptr->set_start_time_millis(start_time_ms);
   private_credential_ptr->set_end_time_millis(end_time_ms);
@@ -127,10 +129,8 @@ CredentialManagerImpl::CreatePrivateCredential(
       std::move(private_credential_ptr), std::move(public_credential_ptr));
 }
 
-std::unique_ptr<proto::PublicCredential>
-CredentialManagerImpl::CreatePublicCredential(
-    proto::PrivateCredential* private_credential,
-    std::vector<uint8_t>* public_key) {
+std::unique_ptr<PublicCredential> CredentialManagerImpl::CreatePublicCredential(
+    PrivateCredential* private_credential, std::vector<uint8_t>* public_key) {
   auto public_credential_ptr = std::make_unique<PublicCredential>();
 
   public_credential_ptr->set_identity_type(private_credential->identity_type());
diff --git a/presence/implementation/credential_manager_impl.h b/presence/implementation/credential_manager_impl.h
index 35e4f20c..d12be6da 100644
--- a/presence/implementation/credential_manager_impl.h
+++ b/presence/implementation/credential_manager_impl.h
@@ -24,9 +24,9 @@
 #include "absl/status/statusor.h"
 #include "absl/strings/string_view.h"
 #include "internal/platform/credential_storage.h"
+#include "internal/proto/credential.pb.h"
 #include "presence/implementation/credential_manager.h"
 #include "presence/presence_identity.h"
-#include "presence/proto/credential.pb.h"
 
 namespace nearby {
 namespace presence {
@@ -45,14 +45,14 @@ class CredentialManagerImpl : public CredentialManager {
   static constexpr int kAesGcmIVSize = 12;
 
   void GenerateCredentials(
-      proto::DeviceMetadata device_metadata,
-      std::vector<proto::IdentityType> identity_types,
+      nearby::internal::DeviceMetadata device_metadata,
+      std::vector<nearby::internal::IdentityType> identity_types,
       int credential_life_cycle_days, int contiguous_copy_of_credentials,
       GenerateCredentialsCallback credentials_generated_cb) override;
 
   void UpdateRemotePublicCredentials(
       std::string account_name,
-      std::vector<proto::PublicCredential> remote_public_creds,
+      std::vector<nearby::internal::PublicCredential> remote_public_creds,
       UpdateRemotePublicCredentialsCallback credentials_updated_cb) override{};
 
   void GetPrivateCredentials(
@@ -77,13 +77,13 @@ class CredentialManagerImpl : public CredentialManager {
   }
 
   absl::StatusOr<std::string> GetBaseEncryptedMetadataKey(
-      const PresenceIdentity& identity) override {
+      const nearby::internal::IdentityType& identity) override {
     return absl::UnimplementedError(
         "GetBaseEncryptedMetadataKey unimplemented");
   }
 
   absl::StatusOr<std::string> EncryptDataElements(
-      const PresenceIdentity& identity, absl::string_view salt,
+      const nearby::internal::IdentityType& identity, absl::string_view salt,
       absl::string_view data_elements) override {
     return absl::UnimplementedError("EncryptDataElements unimplemented");
   }
@@ -91,14 +91,14 @@ class CredentialManagerImpl : public CredentialManager {
  private:
   FRIEND_TEST(CredentialManagerImpl, CreateOneCredentialSuccessfully);
 
-  std::pair<std::unique_ptr<proto::PrivateCredential>,
-            std::unique_ptr<proto::PublicCredential>>
-  CreatePrivateCredential(proto::DeviceMetadata device_metadata,
-                          proto::IdentityType identity_type,
+  std::pair<std::unique_ptr<nearby::internal::PrivateCredential>,
+            std::unique_ptr<nearby::internal::PublicCredential>>
+  CreatePrivateCredential(nearby::internal::DeviceMetadata device_metadata,
+                          nearby::internal::IdentityType identity_type,
                           uint64_t start_time_ms, uint64_t end_time_ms);
 
-  std::unique_ptr<proto::PublicCredential> CreatePublicCredential(
-      proto::PrivateCredential* private_credential_ptr,
+  std::unique_ptr<nearby::internal::PublicCredential> CreatePublicCredential(
+      nearby::internal::PrivateCredential* private_credential_ptr,
       std::vector<uint8_t>* public_key);
 
   std::string EncryptDeviceMetadata(std::string device_metadata_encryption_key,
diff --git a/presence/implementation/credential_manager_impl_test.cc b/presence/implementation/credential_manager_impl_test.cc
index d3c48fc6..d522003e 100644
--- a/presence/implementation/credential_manager_impl_test.cc
+++ b/presence/implementation/credential_manager_impl_test.cc
@@ -20,22 +20,24 @@
 #include "gmock/gmock.h"
 #include "protobuf-matchers/protocol-buffer-matchers.h"
 #include "gtest/gtest.h"
-#include "internal/crypto/aead.h"
-#include "internal/crypto/hkdf.h"
 #include "internal/platform/implementation/crypto.h"
+#include "internal/proto/credential.pb.h"
 #include "presence/implementation/encryption.h"
 
 namespace nearby {
 namespace presence {
 using ::location::nearby::Crypto;
 
-using ::nearby::presence::proto::IdentityType::IDENTITY_TYPE_PRIVATE;
+using ::nearby::internal::DeviceMetadata;
+using ::nearby::internal::PrivateCredential;
+using ::nearby::internal::PublicCredential;
+using ::nearby::internal::IdentityType::IDENTITY_TYPE_PRIVATE;
 using ::proto2::contrib::parse_proto::ParseTestProto;
 using ::protobuf_matchers::EqualsProto;
 
 // TODO(b/241926454): Make sure CredentialManager builds with Github.
 TEST(CredentialManagerImpl, CreateOneCredentialSuccessfully) {
-  proto::DeviceMetadata device_metadata = ParseTestProto(R"pb(
+  DeviceMetadata device_metadata = ParseTestProto(R"pb(
     stable_device_id: "test_device_id"
     ;
     account_name: "test_account";
@@ -50,8 +52,8 @@ TEST(CredentialManagerImpl, CreateOneCredentialSuccessfully) {
       device_metadata, IDENTITY_TYPE_PRIVATE, /* start_time_ms= */ 0,
       /* end_time_ms= */ 1000);
 
-  proto::PrivateCredential* private_credential = credentials.first.get();
-  proto::PublicCredential* public_credential = credentials.second.get();
+  PrivateCredential* private_credential = credentials.first.get();
+  PublicCredential* public_credential = credentials.second.get();
 
   // Verify the private credential.
   EXPECT_THAT(private_credential->device_metadata(),
diff --git a/presence/scan_request.h b/presence/scan_request.h
index a576b225..8d0c2172 100644
--- a/presence/scan_request.h
+++ b/presence/scan_request.h
@@ -19,10 +19,9 @@
 #include <vector>
 
 #include "net/proto2/util/public/message_differencer.h"
+#include "internal/proto/credential.pb.h"
 #include "presence/data_element.h"
 #include "presence/power_mode.h"
-#include "presence/presence_identity.h"
-#include "presence/proto/credential.pb.h"
 
 using MD = proto2::util::MessageDifferencer;
 
@@ -64,7 +63,7 @@ struct LegacyPresenceScanFilter : public ScanFilter {
 
   // Android T needs clients to provide remote public credentials in scan
   // requests.
-  std::vector<proto::PublicCredential> remote_public_credentials;
+  std::vector<nearby::internal::PublicCredential> remote_public_credentials;
 
   // A list of presence actions for matching. Matching condition is met as
   // long as there’s one or more equal actions between Scan actions and
@@ -118,7 +117,7 @@ struct ScanRequest {
 
   // Used to specify which types of remote PublicCredential to use during the
   // scan. If empty, use all available types of remote PublicCredential.
-  std::vector<PresenceIdentity::IdentityType> identity_types;
+  std::vector<nearby::internal::IdentityType> identity_types;
 
   // For new Nearby SDK client (like chromeOs and Android U), use
   // PresenceScanFilter; for Android T, use LegacyPresenceScanFilter.
diff --git a/presence/scan_request_builder.cc b/presence/scan_request_builder.cc
index a0eb3b75..166bcb52 100644
--- a/presence/scan_request_builder.cc
+++ b/presence/scan_request_builder.cc
@@ -19,6 +19,8 @@
 namespace nearby {
 namespace presence {
 
+using ::nearby::internal::IdentityType;
+
 ScanRequestBuilder& ScanRequestBuilder::SetAccountName(
     absl::string_view account_name) {
   request_.account_name = account_name;
@@ -36,13 +38,13 @@ ScanRequestBuilder& ScanRequestBuilder::SetScanType(ScanType scan_type) {
 }
 
 ScanRequestBuilder& ScanRequestBuilder::AddIdentityType(
-    PresenceIdentity::IdentityType identity_type) {
+    IdentityType identity_type) {
   request_.identity_types.push_back(identity_type);
   return *this;
 }
 
 ScanRequestBuilder& ScanRequestBuilder::SetIdentityTypes(
-    std::vector<PresenceIdentity::IdentityType> types) {
+    std::vector<IdentityType> types) {
   request_.identity_types = types;
   return *this;
 }
diff --git a/presence/scan_request_builder.h b/presence/scan_request_builder.h
index e3e18386..6c76f7bd 100644
--- a/presence/scan_request_builder.h
+++ b/presence/scan_request_builder.h
@@ -18,8 +18,8 @@
 #include <vector>
 
 #include "absl/strings/string_view.h"
+#include "internal/proto/credential.pb.h"
 #include "presence/power_mode.h"
-#include "presence/presence_identity.h"
 #include "presence/presence_zone.h"
 #include "presence/scan_request.h"
 
@@ -34,9 +34,9 @@ class ScanRequestBuilder {
   ScanRequestBuilder& SetPowerMode(PowerMode power_mode);
   ScanRequestBuilder& SetScanType(ScanType scan_type);
   ScanRequestBuilder& AddIdentityType(
-      PresenceIdentity::IdentityType identity_type);
+      nearby::internal::IdentityType identity_type);
   ScanRequestBuilder& SetIdentityTypes(
-      std::vector<PresenceIdentity::IdentityType> types);
+      std::vector<nearby::internal::IdentityType> types);
   ScanRequestBuilder& AddScanFilter(ScanFilter scan_filter);
   ScanRequestBuilder& SetScanFilters(std::vector<ScanFilter> filters);
   ScanRequestBuilder& SetUseBle(bool use_ble);
diff --git a/presence/scan_request_builder_test.cc b/presence/scan_request_builder_test.cc
index 9c545ab1..00742c0e 100644
--- a/presence/scan_request_builder_test.cc
+++ b/presence/scan_request_builder_test.cc
@@ -19,20 +19,21 @@
 #include "gmock/gmock.h"
 #include "protobuf-matchers/protocol-buffer-matchers.h"
 #include "gtest/gtest.h"
+#include "internal/proto/credential.pb.h"
 #include "presence/power_mode.h"
-#include "presence/presence_identity.h"
 #include "presence/scan_request.h"
 
 namespace nearby {
 namespace presence {
 
+using ::nearby::internal::IdentityType;
+
 constexpr char kAccountName[] = "Google User";
 constexpr bool kUseBle = true;
 constexpr bool kOnlyScreenOnScan = true;
-const PresenceIdentity::IdentityType kIdentity =
-    PresenceIdentity::IdentityType::kPrivate;
-const ScanType kScanType = ScanType::kPresenceScan;
-const PowerMode kPowerMode = PowerMode::kLowLatency;
+constexpr IdentityType kIdentity = IdentityType::IDENTITY_TYPE_PRIVATE;
+constexpr ScanType kScanType = ScanType::kPresenceScan;
+constexpr PowerMode kPowerMode = PowerMode::kLowLatency;
 
 std::vector<ScanFilter> MockFilters() {
   const LegacyPresenceScanFilter legacyFilter{{.scan_type = kScanType}};
@@ -76,7 +77,7 @@ TEST(ScanRequestBuilderTest, TestAddIdentityType) {
 
 TEST(ScanRequestBuilderTest, TestSetIdentityTypes) {
   ScanRequestBuilder builder;
-  std::vector<PresenceIdentity::IdentityType> types = {kIdentity};
+  std::vector<IdentityType> types = {kIdentity};
   builder.SetIdentityTypes(types);
   ScanRequest sr = builder.Build();
   EXPECT_EQ(sr.identity_types.size(), 1);