diff --git a/design/25530-sumdb.md b/design/25530-sumdb.md
index c1f1647..f6ee726 100644
--- a/design/25530-sumdb.md
+++ b/design/25530-sumdb.md
@@ -287,7 +287,7 @@
 
 - `GOSUMDB=<sumdb-key>` sets the Go checksum database to use,
   where `<sumdb-key>` is a verifier key as defined in
-  [package note](https://godoc.org/golang.org/x/exp/notary/internal/note#hdr-Verifying_Notes).
+  [package note](https://godoc.org/golang.org/x/mod/sumdb/note#hdr-Verifying_Notes).
 
 - `GONOSUMDB=prefix1,prefix2,prefix3` sets a list of module path prefixes,
    again possibly containing globs, that should not be looked up using the database.