diff --git a/PRESUBMIT.py b/PRESUBMIT.py
index 7b45a85766..091037c08e 100755
--- a/PRESUBMIT.py
+++ b/PRESUBMIT.py
@@ -1122,6 +1122,8 @@ def CheckObjcApiSymbols(input_api, output_api, source_file_filter):
     for f in input_api.AffectedSourceFiles(file_filter):
         if not f.LocalPath().endswith('.h') or not 'sdk/objc' in f.LocalPath():
             continue
+        if f.LocalPath().endswith('sdk/objc/base/RTCMacros.h'):
+            continue
         contents = input_api.ReadFile(f)
         for match in rtc_objc_export.finditer(contents):
             export_block = match.group(0)
diff --git a/sdk/objc/base/RTCMacros.h b/sdk/objc/base/RTCMacros.h
index e527ff6bc4..e1c46b23bb 100644
--- a/sdk/objc/base/RTCMacros.h
+++ b/sdk/objc/base/RTCMacros.h
@@ -49,4 +49,9 @@
 #define RTC_FWD_DECL_OBJC_CLASS(classname) typedef struct objc_object classname
 #endif
 
+// TODO(bugs.webrtc.org/6471): This define is a transition aid. It will be
+// deleted together with the RTCRtpFragmentationHeader argument to
+// RTCVideoEncoderCallback, see RTCVideoEncoder.h.
+#define RTC_OBJC_HAVE_LEGACY_RTC_RTP_FRAGMENTATION_HEADER 1
+
 #endif  // SDK_OBJC_BASE_RTCMACROS_H_