diff --git a/static/bidder-info/adgeneration.yaml b/static/bidder-info/adgeneration.yaml
index 424c948e324..befd8ace8fc 100644
--- a/static/bidder-info/adgeneration.yaml
+++ b/static/bidder-info/adgeneration.yaml
@@ -12,3 +12,13 @@ capabilities:
     mediaTypes:
       - banner
       - native
+# cookie-sync (S2S) 検証用。getuid URL / userMacro は backend 仕様確定後に差し替える。
+# 詳細: projects/prebid-server/design/cookie-sync-s2s-design.md
+userSync:
+  redirect:
+    url: "https://d.socdm.com/getuid?gdpr={{.GDPR}}&gdpr_consent={{.GDPRConsent}}&us_privacy={{.USPrivacy}}&gpp={{.GPP}}&gpp_sid={{.GPPSID}}&redirect={{.RedirectURL}}"
+    userMacro: "$UID"
+  # NOT enabled yet: the d.socdm.com /getuid endpoint and user.buyeruid consumption are not
+  # implemented on the backend yet. Keep this syncer disabled by default. A host can turn it on
+  # via config (adapters.adgeneration.usersync.enabled) once the backend is ready.
+  enabled: false