diff --git a/doc/ffmpeg-doc.texi b/doc/ffmpeg-doc.texi
index 673275930d..30bc235f82 100644
--- a/doc/ffmpeg-doc.texi
+++ b/doc/ffmpeg-doc.texi
@@ -1629,6 +1629,9 @@ please use av_log() instead.
 @item
     Do not change code to hide warnings without ensuring that the underlying
     logic is correct and thus the warning was inappropriate.
+@item
+    If you add a new file, give it a proper license header. Do not copy and
+    paste it from a random place, use an existing file as template.
 @end enumerate
 
 We think our rules are not too hard. If you have comments, contact us.