diff --git a/index.bs b/index.bs
index 960f3e90b..8810da9ec 100644
--- a/index.bs
+++ b/index.bs
@@ -5488,6 +5488,11 @@ a numbered step. If outdented, it (today) is rendered as a bullet in the midst o
 
             1. Update <code>|credentialRecord|.[$credential record/signCount$]</code> to the value of |authData|.<code>[=authData/signCount=]</code>.
             1. Update <code>|credentialRecord|.[$credential record/BS$]</code> to the value of |currentBs|.
+            1. OPTIONALLY, if <code>|response|.{{AuthenticatorAssertionResponse/attestationObject}}</code> is present,
+                update <code>|credentialRecord|.[$credential record/attestationObject$]</code>
+                to the value of <code>|response|.{{AuthenticatorAssertionResponse/attestationObject}}</code>
+                and update <code>|credentialRecord|.[$credential record/attestationClientDataJSON$]</code>
+                to the value of <code>|response|.{{AuthenticatorResponse/clientDataJSON}}</code>.
     </li>
 
 1. If all the above steps are successful, continue with the [=authentication ceremony=] as appropriate. Otherwise, fail the