diff --git a/api/video_codecs/video_codec.cc b/api/video_codecs/video_codec.cc
index e96a63a95a..d850917ac2 100644
--- a/api/video_codecs/video_codec.cc
+++ b/api/video_codecs/video_codec.cc
@@ -22,7 +22,8 @@ namespace {
 constexpr char kPayloadNameVp8[] = "VP8";
 constexpr char kPayloadNameVp9[] = "VP9";
 constexpr char kPayloadNameAv1[] = "AV1";
-// TODO(bugs.webrtc.org/13166): Delete after all dependent projects updated.
+// TODO(bugs.webrtc.org/13166): Remove AV1X when backwards compatibility is not
+// needed.
 constexpr char kPayloadNameAv1x[] = "AV1X";
 constexpr char kPayloadNameH264[] = "H264";
 constexpr char kPayloadNameGeneric[] = "Generic";
diff --git a/media/base/media_constants.cc b/media/base/media_constants.cc
index 83be53ae09..da5e7a8adf 100644
--- a/media/base/media_constants.cc
+++ b/media/base/media_constants.cc
@@ -103,7 +103,6 @@ const char kComfortNoiseCodecName[] = "CN";
 const char kVp8CodecName[] = "VP8";
 const char kVp9CodecName[] = "VP9";
 const char kAv1CodecName[] = "AV1";
-const char kAv1xCodecName[] = "AV1X";
 const char kH264CodecName[] = "H264";
 
 // RFC 6184 RTP Payload Format for H.264 video
diff --git a/media/base/media_constants.h b/media/base/media_constants.h
index 313b0f8df9..16c5db92b9 100644
--- a/media/base/media_constants.h
+++ b/media/base/media_constants.h
@@ -123,8 +123,6 @@ extern const char kComfortNoiseCodecName[];
 RTC_EXPORT extern const char kVp8CodecName[];
 RTC_EXPORT extern const char kVp9CodecName[];
 RTC_EXPORT extern const char kAv1CodecName[];
-// TODO(bugs.webrtc.org/13166): Delete after all dependent projects updated.
-RTC_EXPORT extern const char kAv1xCodecName[];
 RTC_EXPORT extern const char kH264CodecName[];
 
 // RFC 6184 RTP Payload Format for H.264 video
diff --git a/media/engine/webrtc_video_engine.cc b/media/engine/webrtc_video_engine.cc
index bdce2ba7b6..359cbd3a19 100644
--- a/media/engine/webrtc_video_engine.cc
+++ b/media/engine/webrtc_video_engine.cc
@@ -53,6 +53,10 @@ using ::webrtc::ParseRtpSsrc;
 const int kMinLayerSize = 16;
 constexpr int64_t kUnsignaledSsrcCooldownMs = rtc::kNumMillisecsPerSec / 2;
 
+// TODO(bugs.webrtc.org/13166): Remove AV1X when backwards compatibility is not
+// needed.
+constexpr char kAv1xCodecName[] = "AV1X";
+
 const char* StreamTypeToString(
     webrtc::VideoSendStream::StreamStats::StreamType type) {
   switch (type) {