diff --git a/packager/hls/base/simple_hls_notifier.cc b/packager/hls/base/simple_hls_notifier.cc
index 2387ace981..11dde8e31e 100644
--- a/packager/hls/base/simple_hls_notifier.cc
+++ b/packager/hls/base/simple_hls_notifier.cc
@@ -16,14 +16,10 @@
 #include "packager/base/strings/string_number_conversions.h"
 #include "packager/base/strings/stringprintf.h"
 #include "packager/hls/base/media_playlist.h"
-#include "packager/media/base/common_pssh_generator.h"
-#include "packager/media/base/fairplay_pssh_generator.h"
+#include "packager/media/base/protection_system_ids.h"
 #include "packager/media/base/protection_system_specific_info.h"
 #include "packager/media/base/proto_json_util.h"
-#include "packager/media/base/raw_key_source.h"
-#include "packager/media/base/widevine_key_source.h"
 #include "packager/media/base/widevine_pssh_data.pb.h"
-#include "packager/media/base/widevine_pssh_generator.h"
 
 DEFINE_bool(enable_legacy_widevine_hls_signaling,
             false,
diff --git a/packager/hls/base/simple_hls_notifier_unittest.cc b/packager/hls/base/simple_hls_notifier_unittest.cc
index a4fbc4aedd..17f6943c88 100644
--- a/packager/hls/base/simple_hls_notifier_unittest.cc
+++ b/packager/hls/base/simple_hls_notifier_unittest.cc
@@ -14,13 +14,9 @@
 #include "packager/base/files/file_path.h"
 #include "packager/hls/base/mock_media_playlist.h"
 #include "packager/hls/base/simple_hls_notifier.h"
-#include "packager/media/base/common_pssh_generator.h"
-#include "packager/media/base/fairplay_pssh_generator.h"
+#include "packager/media/base/protection_system_ids.h"
 #include "packager/media/base/protection_system_specific_info.h"
-#include "packager/media/base/raw_key_source.h"
-#include "packager/media/base/widevine_key_source.h"
 #include "packager/media/base/widevine_pssh_data.pb.h"
-#include "packager/media/base/widevine_pssh_generator.h"
 
 DECLARE_bool(enable_legacy_widevine_hls_signaling);
 
diff --git a/packager/media/base/common_pssh_generator.cc b/packager/media/base/common_pssh_generator.cc
index a54ad16e7b..c411e5a201 100644
--- a/packager/media/base/common_pssh_generator.cc
+++ b/packager/media/base/common_pssh_generator.cc
@@ -6,6 +6,8 @@
 
 #include "packager/media/base/common_pssh_generator.h"
 
+#include "packager/media/base/protection_system_ids.h"
+
 namespace shaka {
 namespace media {
 namespace {
diff --git a/packager/media/base/common_pssh_generator.h b/packager/media/base/common_pssh_generator.h
index 71a7eb0546..6179c59978 100644
--- a/packager/media/base/common_pssh_generator.h
+++ b/packager/media/base/common_pssh_generator.h
@@ -12,13 +12,6 @@
 namespace shaka {
 namespace media {
 
-// Common SystemID defined by EME, which requires Key System implementations
-// supporting ISO Common Encryption to support this SystemID and format.
-// https://goo.gl/kUv2Xd
-const uint8_t kCommonSystemId[] = {0x10, 0x77, 0xef, 0xec, 0xc0, 0xb2,
-                                   0x4d, 0x02, 0xac, 0xe3, 0x3c, 0x1e,
-                                   0x52, 0xe2, 0xfb, 0x4b};
-
 class CommonPsshGenerator : public PsshGenerator {
  public:
   CommonPsshGenerator();
diff --git a/packager/media/base/fairplay_pssh_generator.cc b/packager/media/base/fairplay_pssh_generator.cc
index b2562926a3..9fd509a413 100644
--- a/packager/media/base/fairplay_pssh_generator.cc
+++ b/packager/media/base/fairplay_pssh_generator.cc
@@ -6,6 +6,8 @@
 
 #include "packager/media/base/fairplay_pssh_generator.h"
 
+#include "packager/media/base/protection_system_ids.h"
+
 namespace shaka {
 namespace media {
 namespace {
diff --git a/packager/media/base/fairplay_pssh_generator.h b/packager/media/base/fairplay_pssh_generator.h
index 9ab95ecfd9..285219aaf6 100644
--- a/packager/media/base/fairplay_pssh_generator.h
+++ b/packager/media/base/fairplay_pssh_generator.h
@@ -12,12 +12,6 @@
 namespace shaka {
 namespace media {
 
-// Unofficial FairPlay system id extracted from
-// https://forums.developer.apple.com/thread/6185.
-const uint8_t kFairPlaySystemId[] = {0x29, 0x70, 0x1F, 0xE4, 0x3C, 0xC7,
-                                     0x4A, 0x34, 0x8C, 0x5B, 0xAE, 0x90,
-                                     0xC7, 0x43, 0x9A, 0x47};
-
 class FairPlayPsshGenerator : public PsshGenerator {
  public:
   FairPlayPsshGenerator();
diff --git a/packager/media/base/media_base.gyp b/packager/media/base/media_base.gyp
index ca3534b94c..00fe9f0aef 100644
--- a/packager/media/base/media_base.gyp
+++ b/packager/media/base/media_base.gyp
@@ -81,6 +81,7 @@
         'playready_pssh_generator.cc',
         'playready_pssh_generator.h',
         'producer_consumer_queue.h',
+        'protection_system_ids.h',
         'protection_system_specific_info.cc',
         'protection_system_specific_info.h',
         'proto_json_util.cc',
diff --git a/packager/media/base/playready_key_source.cc b/packager/media/base/playready_key_source.cc
index fa13ba0d96..c390dad53b 100644
--- a/packager/media/base/playready_key_source.cc
+++ b/packager/media/base/playready_key_source.cc
@@ -15,7 +15,7 @@
 #include "packager/media/base/buffer_writer.h"
 #include "packager/media/base/http_key_fetcher.h"
 #include "packager/media/base/key_source.h"
-#include "packager/media/base/playready_pssh_generator.h"
+#include "packager/media/base/protection_system_ids.h"
 #include "packager/status_macros.h"
 
 namespace shaka {
diff --git a/packager/media/base/playready_pssh_generator.cc b/packager/media/base/playready_pssh_generator.cc
index e319b124c9..0c1b168564 100644
--- a/packager/media/base/playready_pssh_generator.cc
+++ b/packager/media/base/playready_pssh_generator.cc
@@ -17,6 +17,7 @@
 #include "packager/base/strings/string_number_conversions.h"
 #include "packager/base/strings/string_util.h"
 #include "packager/media/base/buffer_writer.h"
+#include "packager/media/base/protection_system_ids.h"
 
 namespace shaka {
 namespace media {
diff --git a/packager/media/base/playready_pssh_generator.h b/packager/media/base/playready_pssh_generator.h
index d6e03c7201..485568e214 100644
--- a/packager/media/base/playready_pssh_generator.h
+++ b/packager/media/base/playready_pssh_generator.h
@@ -12,11 +12,6 @@
 namespace shaka {
 namespace media {
 
-// SystemID defined for PlayReady Drm.
-const uint8_t kPlayReadySystemId[] = {0x9a, 0x04, 0xf0, 0x79, 0x98, 0x40,
-                                      0x42, 0x86, 0xab, 0x92, 0xe6, 0x5b,
-                                      0xe0, 0x88, 0x5f, 0x95};
-
 class PlayReadyPsshGenerator : public PsshGenerator {
  public:
   PlayReadyPsshGenerator();
diff --git a/packager/media/base/protection_system_ids.h b/packager/media/base/protection_system_ids.h
new file mode 100644
index 0000000000..ba4b8689f3
--- /dev/null
+++ b/packager/media/base/protection_system_ids.h
@@ -0,0 +1,37 @@
+// Copyright 2018 Google LLC. All rights reserved.
+//
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file or at
+// https://developers.google.com/open-source/licenses/bsd
+
+#ifndef PACKAGER_MEDIA_BASE_PROTECTION_SYSTEM_IDS_H_
+#define PACKAGER_MEDIA_BASE_PROTECTION_SYSTEM_IDS_H_
+
+namespace shaka {
+namespace media {
+
+// Common SystemID defined by EME, which requires Key System implementations
+// supporting ISO Common Encryption to support this SystemID and format.
+// https://goo.gl/kUv2Xd
+const uint8_t kCommonSystemId[] = {0x10, 0x77, 0xef, 0xec, 0xc0, 0xb2,
+                                   0x4d, 0x02, 0xac, 0xe3, 0x3c, 0x1e,
+                                   0x52, 0xe2, 0xfb, 0x4b};
+
+// Unofficial FairPlay system id extracted from
+// https://forums.developer.apple.com/thread/6185.
+const uint8_t kFairPlaySystemId[] = {0x29, 0x70, 0x1F, 0xE4, 0x3C, 0xC7,
+                                     0x4A, 0x34, 0x8C, 0x5B, 0xAE, 0x90,
+                                     0xC7, 0x43, 0x9A, 0x47};
+
+const uint8_t kPlayReadySystemId[] = {0x9a, 0x04, 0xf0, 0x79, 0x98, 0x40,
+                                      0x42, 0x86, 0xab, 0x92, 0xe6, 0x5b,
+                                      0xe0, 0x88, 0x5f, 0x95};
+
+const uint8_t kWidevineSystemId[] = {0xed, 0xef, 0x8b, 0xa9, 0x79, 0xd6,
+                                     0x4a, 0xce, 0xa3, 0xc8, 0x27, 0xdc,
+                                     0xd5, 0x1d, 0x21, 0xed};
+
+}  // namespace media
+}  // namespace shaka
+
+#endif  // PACKAGER_MEDIA_BASE_PROTECTION_SYSTEM_IDS_H_
diff --git a/packager/media/base/raw_key_source.cc b/packager/media/base/raw_key_source.cc
index 32963114e7..63af61170e 100644
--- a/packager/media/base/raw_key_source.cc
+++ b/packager/media/base/raw_key_source.cc
@@ -9,7 +9,6 @@
 #include <algorithm>
 #include "packager/base/logging.h"
 #include "packager/base/strings/string_number_conversions.h"
-#include "packager/media/base/common_pssh_generator.h"
 #include "packager/media/base/key_source.h"
 #include "packager/status_macros.h"
 
diff --git a/packager/media/base/widevine_key_source.cc b/packager/media/base/widevine_key_source.cc
index 30e5465d5b..5f75eb2176 100644
--- a/packager/media/base/widevine_key_source.cc
+++ b/packager/media/base/widevine_key_source.cc
@@ -12,13 +12,13 @@
 #include "packager/media/base/http_key_fetcher.h"
 #include "packager/media/base/network_util.h"
 #include "packager/media/base/producer_consumer_queue.h"
+#include "packager/media/base/protection_system_ids.h"
 #include "packager/media/base/protection_system_specific_info.h"
 #include "packager/media/base/proto_json_util.h"
 #include "packager/media/base/pssh_generator_util.h"
 #include "packager/media/base/rcheck.h"
 #include "packager/media/base/request_signer.h"
 #include "packager/media/base/widevine_common_encryption.pb.h"
-#include "packager/media/base/widevine_pssh_generator.h"
 
 namespace shaka {
 namespace media {
diff --git a/packager/media/base/widevine_key_source_unittest.cc b/packager/media/base/widevine_key_source_unittest.cc
index dcb7f030a7..70d5f67fb2 100644
--- a/packager/media/base/widevine_key_source_unittest.cc
+++ b/packager/media/base/widevine_key_source_unittest.cc
@@ -12,8 +12,8 @@
 #include "packager/base/base64.h"
 #include "packager/base/strings/string_number_conversions.h"
 #include "packager/base/strings/stringprintf.h"
-#include "packager/media/base/common_pssh_generator.h"
 #include "packager/media/base/key_fetcher.h"
+#include "packager/media/base/protection_system_ids.h"
 #include "packager/media/base/request_signer.h"
 #include "packager/media/base/widevine_key_source.h"
 #include "packager/media/base/widevine_pssh_generator.h"
diff --git a/packager/media/base/widevine_pssh_generator.cc b/packager/media/base/widevine_pssh_generator.cc
index 83b360f056..5cd4b7b370 100644
--- a/packager/media/base/widevine_pssh_generator.cc
+++ b/packager/media/base/widevine_pssh_generator.cc
@@ -6,6 +6,7 @@
 
 #include "packager/media/base/widevine_pssh_generator.h"
 
+#include "packager/media/base/protection_system_ids.h"
 #include "packager/media/base/widevine_pssh_data.pb.h"
 
 namespace shaka {
diff --git a/packager/media/base/widevine_pssh_generator.h b/packager/media/base/widevine_pssh_generator.h
index b0aedbc225..5ef228fbdc 100644
--- a/packager/media/base/widevine_pssh_generator.h
+++ b/packager/media/base/widevine_pssh_generator.h
@@ -13,10 +13,6 @@
 namespace shaka {
 namespace media {
 
-const uint8_t kWidevineSystemId[] = {0xed, 0xef, 0x8b, 0xa9, 0x79, 0xd6,
-                                     0x4a, 0xce, 0xa3, 0xc8, 0x27, 0xdc,
-                                     0xd5, 0x1d, 0x21, 0xed};
-
 class WidevinePsshGenerator : public PsshGenerator {
  public:
   explicit WidevinePsshGenerator(FourCC protection_scheme);