diff --git a/99.md b/99.md
index 274e5afb..584af28f 100644
--- a/99.md
+++ b/99.md
@@ -48,6 +48,9 @@ The following tags, used for structured metadata, are standardized and SHOULD be
 Other standard tags that might be useful.
 
 - `"g"`, a geohash for more precise location
+- `"a"`, one or more a tags referencing kind `30009` Badge Definition events (NIP-58)
+
+When `"a"` tags refering kind `30009` events exist, a client CAN verify a user has been awarded all the respective badges before granting access to the product or service defined by the classified listing event.
 
 ## Example Event
 
@@ -73,7 +76,7 @@ Other standard tags that might be useful.
     ],
     [
       "a",
-      "30023:a695f6b60119d9521934a691347d9f78e8770b56da16bb255ee286ddf9fda919:ipsum",
+      "30009:a695f6b60119d9521934a691347d9f78e8770b56da16bb255ee286ddf9fda919:coolkids-membersbadge",
       "wss://relay.nostr.org"
     ]
   ],