diff --git a/src/exchange/taler-exchange-httpd_keys.c b/src/exchange/taler-exchange-httpd_keys.c
index 08c83ddab..4fc07ada7 100644
--- a/src/exchange/taler-exchange-httpd_keys.c
+++ b/src/exchange/taler-exchange-httpd_keys.c
@@ -2155,6 +2155,8 @@ finish_keys_response (struct TEH_KeyStateHandle *ksh)
                                         dk->meta.expire_deposit),
             GNUNET_JSON_pack_timestamp ("stamp_expire_legal",
                                         dk->meta.expire_legal),
+            GNUNET_JSON_pack_uint32 ("age_mask",
+                                     dk->meta.age_mask.bits),
             TALER_JSON_pack_denom_pub ("denom_pub",
                                        &dk->denom_pub),
             TALER_JSON_pack_amount ("value",