diff --git a/packager/media/base/container_names.cc b/packager/media/base/container_names.cc
index 3d32ed3384..1e57c8a69e 100644
--- a/packager/media/base/container_names.cc
+++ b/packager/media/base/container_names.cc
@@ -963,6 +963,7 @@ static bool CheckMov(const uint8_t* buffer, int buffer_size) {
     switch (atomtype) {
       case TAG('f','t','y','p'):
       case TAG('p','d','i','n'):
+      case TAG('b','l','o','c'):
       case TAG('m','o','o','v'):
       case TAG('m','o','o','f'):
       case TAG('m','f','r','a'):
@@ -975,7 +976,7 @@ static bool CheckMov(const uint8_t* buffer, int buffer_size) {
       case TAG('s','i','d','x'):
       case TAG('s','s','i','x'):
       case TAG('p','r','f','t'):
-      case TAG('b','l','o','c'):
+      case TAG('u','u','i','d'):
         break;
       default:
         return false;
diff --git a/packager/media/formats/mp4/box_reader.cc b/packager/media/formats/mp4/box_reader.cc
index 525e8ec725..3ea717ce24 100644
--- a/packager/media/formats/mp4/box_reader.cc
+++ b/packager/media/formats/mp4/box_reader.cc
@@ -92,6 +92,7 @@ bool BoxReader::IsValidTopLevelBox(const FourCC& type) {
     case FOURCC_sidx:
     case FOURCC_ssix:
     case FOURCC_prft:
+    case FOURCC_uuid:
       return true;
     default:
       // Hex is used to show nonprintable characters and aid in debugging