diff --git a/api/frame_transformer_interface.h b/api/frame_transformer_interface.h
index fba09d5ff0..92832c00bc 100644
--- a/api/frame_transformer_interface.h
+++ b/api/frame_transformer_interface.h
@@ -57,9 +57,9 @@ class TransformableVideoFrameInterface : public TransformableFrameInterface {
   // when the transformation applied to the frame is encryption/decryption, the
   // additional data holds the serialized generic frame descriptor extension
   // calculated in webrtc::RtpDescriptorAuthentication.
-  // TODO(bugs.webrtc.org/11380) remove from interface once
-  // webrtc::RtpDescriptorAuthentication is exposed in api/.
-  virtual std::vector<uint8_t> GetAdditionalData() const = 0;
+  // This has been superseeded by GetMetadata() and will be removed shortly.
+  [[deprecated("https://crbug.com/1414370")]] virtual std::vector<uint8_t>
+  GetAdditionalData() const = 0;
 
   virtual const VideoFrameMetadata& GetMetadata() const = 0;
   // TODO(https://crbug.com/webrtc/14709): Make pure virtual when Chromium MOCK