diff --git a/libwvdrmengine/cdm/core/src/device_files.cpp b/libwvdrmengine/cdm/core/src/device_files.cpp
index 7c21b8e4..807681fb 100644
--- a/libwvdrmengine/cdm/core/src/device_files.cpp
+++ b/libwvdrmengine/cdm/core/src/device_files.cpp
@@ -71,8 +71,6 @@ using video_widevine_client::sdk::
 
 namespace {
 
-const char kAtscCertificateFileName[] = "atsccert.bin";
-const char kCertificateFileName[] = "cert.bin";
 const char kHlsAttributesFileNameExt[] = ".hal";
 const char kUsageInfoFileNamePrefix[] = "usage";
 const char kUsageInfoFileNameExt[] = ".bin";
diff --git a/libwvdrmengine/cdm/util/include/file_store.h b/libwvdrmengine/cdm/util/include/file_store.h
index 94dded6a..a2310e9e 100644
--- a/libwvdrmengine/cdm/util/include/file_store.h
+++ b/libwvdrmengine/cdm/util/include/file_store.h
@@ -18,6 +18,13 @@
 
 namespace wvcdm {
 
+static const std::string kAtscCertificateFileName = "atsccert.bin";
+static const std::string kCertificateFileName = "cert1.bin";
+static const std::string kCertificateFileNameExt = ".bin";
+static const std::string kCertificateFileNamePrefix = "cert1_";
+static const std::string kLegacyCertificateFileName = "cert.bin";
+static const std::string kLegacyCertificateFileNamePrefix = "cert";
+
 // File class. The implementation is platform dependent.
 class CORE_UTIL_EXPORT File {
  public:
diff --git a/libwvdrmengine/cdm/util/src/file_store.cpp b/libwvdrmengine/cdm/util/src/file_store.cpp
index b3aa7bb8..76d24c4f 100644
--- a/libwvdrmengine/cdm/util/src/file_store.cpp
+++ b/libwvdrmengine/cdm/util/src/file_store.cpp
@@ -29,9 +29,6 @@
 namespace wvcdm {
 
 namespace {
-const char kCertificateFileNamePrefix[] = "cert";
-const char kCertificateFileNameExt[] = ".bin";
-const char kCertificateFileName[] = "cert.bin";
 
 std::string GetFileNameSafeHash(const std::string& input) {
   std::vector<uint8_t> hash(MD5_DIGEST_LENGTH);
@@ -54,6 +51,10 @@ std::string GetFileNameForIdentifier(const std::string path,
   if (file_name == kCertificateFileName && !identifier.empty()) {
     const std::string hash = GetFileNameSafeHash(identifier);
     file_name = kCertificateFileNamePrefix + hash + kCertificateFileNameExt;
+  } else if (file_name == kLegacyCertificateFileName && !identifier.empty()) {
+    const std::string hash = GetFileNameSafeHash(identifier);
+    file_name =
+        kLegacyCertificateFileNamePrefix + hash + kCertificateFileNameExt;
   }
 
   if (dir_path.empty())
diff --git a/libwvdrmengine/cdm/util/test/file_store_unittest.cpp b/libwvdrmengine/cdm/util/test/file_store_unittest.cpp
index bae0aea0..64b7d8df 100644
--- a/libwvdrmengine/cdm/util/test/file_store_unittest.cpp
+++ b/libwvdrmengine/cdm/util/test/file_store_unittest.cpp
@@ -18,7 +18,10 @@ const std::string kTestFileName2 = "test2.txt";
 const std::string kTestFileName3 = "test3.other";
 const std::string kTestFileNameExt = ".txt";
 const std::string kTestFileNameExt3 = ".other";
+const std::string kTestIdentifier1 = "some_identifier";
+const std::string kTestIdentifier2 = "some_other_identifier";
 const std::string kWildcard = "*";
+const std::string kUnderscore = "_";
 }  // namespace
 
 class FileTest : public testing::Test {
@@ -175,4 +178,182 @@ TEST_F(FileTest, ListFiles) {
   EXPECT_EQ(0u, names.size());
 }
 
+TEST_F(FileTest, CreateGlobalCertificates) {
+  // Clear directory
+  std::vector<std::string> names;
+  std::string path_dir = test_vectors::kTestDir;
+  std::string wild_card_path = path_dir + kWildcard;
+  file_system_.Remove(wild_card_path);
+  if (file_system_.List(path_dir, &names)) {
+    EXPECT_EQ(0u, names.size());
+  }
+
+  // Create certificates and verify that they exist
+  std::string certificate_path = test_vectors::kTestDir + kCertificateFileName;
+  std::string legacy_certificate_path =
+      test_vectors::kTestDir + kLegacyCertificateFileName;
+
+  std::unique_ptr<File> file =
+      file_system_.Open(certificate_path, FileSystem::kCreate);
+  ASSERT_TRUE(file);
+  file = file_system_.Open(legacy_certificate_path, FileSystem::kCreate);
+  ASSERT_TRUE(file);
+  EXPECT_TRUE(file_system_.IsGlobal());
+
+  EXPECT_TRUE(file_system_.Exists(certificate_path));
+  EXPECT_TRUE(file_system_.Exists(legacy_certificate_path));
+
+  EXPECT_TRUE(file_system_.List(path_dir, &names));
+
+  // Should find two files. Order not important.
+  EXPECT_EQ(2u, names.size());
+  EXPECT_THAT(names, ::testing::UnorderedElementsAre(
+                         kCertificateFileName, kLegacyCertificateFileName));
+}
+
+TEST_F(FileTest, CreateCertificates) {
+  // Clear directory
+  std::vector<std::string> names;
+  std::string path_dir = test_vectors::kTestDir;
+  std::string wild_card_path = path_dir + kWildcard;
+  file_system_.Remove(wild_card_path);
+  if (file_system_.List(path_dir, &names)) {
+    EXPECT_EQ(0u, names.size());
+  }
+
+  std::string certificate_path = test_vectors::kTestDir + kCertificateFileName;
+  std::string legacy_certificate_path =
+      test_vectors::kTestDir + kLegacyCertificateFileName;
+
+  // Create Global certificates
+  std::unique_ptr<File> file =
+      file_system_.Open(certificate_path, FileSystem::kCreate);
+  ASSERT_TRUE(file);
+  file = file_system_.Open(legacy_certificate_path, FileSystem::kCreate);
+  ASSERT_TRUE(file);
+  EXPECT_TRUE(file_system_.IsGlobal());
+
+  // Create certificates with first identifier
+  file_system_.set_identifier(kTestIdentifier1);
+  file = file_system_.Open(certificate_path, FileSystem::kCreate);
+  ASSERT_TRUE(file);
+  file = file_system_.Open(legacy_certificate_path, FileSystem::kCreate);
+  ASSERT_TRUE(file);
+  EXPECT_TRUE(!file_system_.IsGlobal());
+
+  // Create certificates with second identifier
+  file_system_.set_identifier(kTestIdentifier2);
+  file = file_system_.Open(certificate_path, FileSystem::kCreate);
+  ASSERT_TRUE(file);
+  file = file_system_.Open(legacy_certificate_path, FileSystem::kCreate);
+  ASSERT_TRUE(file);
+  EXPECT_TRUE(!file_system_.IsGlobal());
+
+  EXPECT_TRUE(file_system_.Exists(certificate_path));
+  EXPECT_TRUE(file_system_.Exists(legacy_certificate_path));
+
+  EXPECT_TRUE(file_system_.List(path_dir, &names));
+
+  // Should find six files. Order not important.
+  bool is_global_certificate_present = false;
+  bool is_global_legacy_certificate_present = false;
+  size_t certificate_count = 0;
+  size_t legacy_certificate_count = 0;
+  EXPECT_EQ(6u, names.size());
+  for (size_t i = 0; i < names.size(); ++i) {
+    if (names[i].size() > kCertificateFileName.size()) {
+      if (names[i].compare(0, kCertificateFileNamePrefix.size(),
+                           kCertificateFileNamePrefix) == 0)
+        ++certificate_count;
+      else if (names[i].compare(0, kLegacyCertificateFileNamePrefix.size(),
+                                kLegacyCertificateFileNamePrefix) == 0)
+        ++legacy_certificate_count;
+    } else if (names[i].compare(kCertificateFileName) == 0) {
+      is_global_certificate_present = true;
+    } else if (names[i].compare(kLegacyCertificateFileName) == 0) {
+      is_global_legacy_certificate_present = true;
+    } else {
+      EXPECT_TRUE(false);
+    }
+  }
+  EXPECT_EQ(2, certificate_count);
+  EXPECT_EQ(2, legacy_certificate_count);
+  EXPECT_TRUE(is_global_certificate_present);
+  EXPECT_TRUE(is_global_legacy_certificate_present);
+}
+
+TEST_F(FileTest, RemoveCertificates) {
+  // Clear directory
+  std::vector<std::string> names;
+  std::string path_dir = test_vectors::kTestDir;
+  std::string wild_card_path = path_dir + kWildcard;
+  file_system_.Remove(wild_card_path);
+  if (file_system_.List(path_dir, &names)) {
+    EXPECT_EQ(0u, names.size());
+  }
+
+  std::string certificate_path = test_vectors::kTestDir + kCertificateFileName;
+  std::string legacy_certificate_path =
+      test_vectors::kTestDir + kLegacyCertificateFileName;
+
+  // Create Global certificates
+  std::unique_ptr<File> file =
+      file_system_.Open(certificate_path, FileSystem::kCreate);
+  ASSERT_TRUE(file);
+  file = file_system_.Open(legacy_certificate_path, FileSystem::kCreate);
+  ASSERT_TRUE(file);
+  EXPECT_TRUE(file_system_.IsGlobal());
+
+  // Create certificates with first identifier
+  file_system_.set_identifier(kTestIdentifier1);
+  file = file_system_.Open(certificate_path, FileSystem::kCreate);
+  ASSERT_TRUE(file);
+  file = file_system_.Open(legacy_certificate_path, FileSystem::kCreate);
+  ASSERT_TRUE(file);
+  EXPECT_TRUE(!file_system_.IsGlobal());
+
+  // Create certificates with second identifier
+  file_system_.set_identifier(kTestIdentifier2);
+  file = file_system_.Open(certificate_path, FileSystem::kCreate);
+  ASSERT_TRUE(file);
+  file = file_system_.Open(legacy_certificate_path, FileSystem::kCreate);
+  ASSERT_TRUE(file);
+  EXPECT_TRUE(!file_system_.IsGlobal());
+
+  EXPECT_TRUE(file_system_.Exists(certificate_path));
+  EXPECT_TRUE(file_system_.Exists(legacy_certificate_path));
+
+  EXPECT_TRUE(file_system_.List(path_dir, &names));
+
+  EXPECT_EQ(6u, names.size());
+
+  // Remove all even number listed files
+  for (size_t i = 0; i < names.size(); ++i) {
+    if (i % 2 == 0) {
+      EXPECT_TRUE(file_system_.Remove(test_vectors::kTestDir + names[i]));
+    }
+  }
+
+  // Verify that they have been removed
+  for (size_t i = 0; i < names.size(); ++i) {
+    if (i % 2 == 1) {
+      EXPECT_TRUE(file_system_.Exists(test_vectors::kTestDir + names[i]));
+    } else {
+      EXPECT_FALSE(file_system_.Exists(test_vectors::kTestDir + names[i]));
+    }
+  }
+
+  // Remove all odd number listed files
+  for (size_t i = 0; i < names.size(); ++i) {
+    if (i % 2 == 1) {
+      EXPECT_TRUE(file_system_.Remove(test_vectors::kTestDir + names[i]));
+    }
+  }
+
+  // Verify that all have been removed
+  for (size_t i = 0; i < names.size(); ++i) {
+    EXPECT_FALSE(file_system_.Exists(test_vectors::kTestDir + names[i]));
+  }
+}
+
 }  // namespace wvcdm