diff --git a/api/frame_transformer_interface.h b/api/frame_transformer_interface.h
index f841072871..aa695e5331 100644
--- a/api/frame_transformer_interface.h
+++ b/api/frame_transformer_interface.h
@@ -58,14 +58,6 @@ class TransformableVideoFrameInterface : public TransformableFrameInterface {
   virtual ~TransformableVideoFrameInterface() = default;
   virtual bool IsKeyFrame() const = 0;
 
-  // Returns data needed in the frame transformation logic; for example,
-  // when the transformation applied to the frame is encryption/decryption, the
-  // additional data holds the serialized generic frame descriptor extension
-  // calculated in webrtc::RtpDescriptorAuthentication.
-  // This has been superseeded by GetMetadata() and will be removed shortly.
-  [[deprecated("https://crbug.com/1414370")]] virtual std::vector<uint8_t>
-  GetAdditionalData() const = 0;
-
   // The returned const ref may become invalid due to later SetMetadata calls,
   // or other modifications. Use Metadata() instead.
   virtual const VideoFrameMetadata& GetMetadata() const = 0;
diff --git a/api/test/mock_transformable_video_frame.h b/api/test/mock_transformable_video_frame.h
index 35ce8e562a..9d56a290ee 100644
--- a/api/test/mock_transformable_video_frame.h
+++ b/api/test/mock_transformable_video_frame.h
@@ -26,7 +26,6 @@ class MockTransformableVideoFrame
   MOCK_METHOD(uint32_t, GetTimestamp, (), (const, override));
   MOCK_METHOD(uint32_t, GetSsrc, (), (const, override));
   MOCK_METHOD(bool, IsKeyFrame, (), (const, override));
-  MOCK_METHOD(std::vector<uint8_t>, GetAdditionalData, (), (const, override));
   MOCK_METHOD(const webrtc::VideoFrameMetadata&,
               GetMetadata,
               (),
diff --git a/modules/rtp_rtcp/source/rtp_sender_video_frame_transformer_delegate.cc b/modules/rtp_rtcp/source/rtp_sender_video_frame_transformer_delegate.cc
index 4057d32e15..717cbb470a 100644
--- a/modules/rtp_rtcp/source/rtp_sender_video_frame_transformer_delegate.cc
+++ b/modules/rtp_rtcp/source/rtp_sender_video_frame_transformer_delegate.cc
@@ -66,10 +66,6 @@ class TransformableVideoSenderFrame : public TransformableVideoFrameInterface {
     return frame_type_ == VideoFrameType::kVideoFrameKey;
   }
 
-  std::vector<uint8_t> GetAdditionalData() const override {
-    return RtpDescriptorAuthentication(header_);
-  }
-
   const VideoFrameMetadata& GetMetadata() const override { return metadata_; }
 
   VideoFrameMetadata Metadata() const override {
diff --git a/modules/rtp_rtcp/source/rtp_video_stream_receiver_frame_transformer_delegate.cc b/modules/rtp_rtcp/source/rtp_video_stream_receiver_frame_transformer_delegate.cc
index e2e9fec5f1..c66c05b8ca 100644
--- a/modules/rtp_rtcp/source/rtp_video_stream_receiver_frame_transformer_delegate.cc
+++ b/modules/rtp_rtcp/source/rtp_video_stream_receiver_frame_transformer_delegate.cc
@@ -51,10 +51,6 @@ class TransformableVideoReceiverFrame
     return frame_->FrameType() == VideoFrameType::kVideoFrameKey;
   }
 
-  std::vector<uint8_t> GetAdditionalData() const override {
-    return RtpDescriptorAuthentication(frame_->GetRtpVideoHeader());
-  }
-
   const VideoFrameMetadata& GetMetadata() const override { return metadata_; }
 
   VideoFrameMetadata Metadata() const override { return metadata_; }