diff --git a/go/facts/facts.go b/go/facts/facts.go
index 270471d..c6333cd 100644
--- a/go/facts/facts.go
+++ b/go/facts/facts.go
@@ -17,6 +17,9 @@
 // secret is withheld, an address is replaced by one from a documentation range, and a machine's name, a
 // site, an account and a public domain are replaced wherever they appear. So a snapshot can be copied
 // into a test, a replay or a pull request without carrying anything of the installation it came from.
+//
+// Copied from mesh-controller internal/facts at 6c2a8d62 (R4b, issue 1380); the one change is each machine's
+// Grants and Bindings, from format 2.
 package facts
 
 import (