diff --git a/index.bs b/index.bs
index f537878e3..19975144b 100644
--- a/index.bs
+++ b/index.bs
@@ -4811,9 +4811,11 @@ leave the [=authData/signCount=]
in the [=authenticator data=] cons
A [=[RP]=] stores the [=signature counter=] of the most recent [=authenticatorGetAssertion=] operation. (Or the counter from the [=authenticatorMakeCredential=] operation if no [=authenticatorGetAssertion=] has ever been performed on a credential.) In subsequent
[=authenticatorGetAssertion=] operations, the [=[RP]=] compares the stored [=signature counter=] value with the new
-[=authData/signCount=]
value returned in the assertion's [=authenticator data=]. If either is non-zero, and the new [=authData/signCount=]
value is less than or equal to the stored value, a cloned authenticator may exist, or the authenticator may be malfunctioning.
+[=authData/signCount=]
value returned in the assertion's [=authenticator data=]. If either is non-zero, and the new [=authData/signCount=]
value is less than or equal to the stored value, a cloned authenticator may exist, or the authenticator may be malfunctioning,
+or a race condition might exist where the relying party is receiving and processing assertions
+in an order other than the order they were generated at the authenticator.
-Detecting a [=signature counter=] mismatch does not indicate whether the current operation was performed by a cloned authenticator or the original authenticator. [=[RPS]=] should address this situation appropriately relative to their individual situations, i.e., their risk tolerance.
+Detecting a [=signature counter=] mismatch does not indicate whether the current operation was performed by a cloned authenticator or the original authenticator. [=[RPS]=] should address this situation appropriately relative to their individual situations, i.e., their risk tolerance or operational factors that might result in an acceptable reason for non-increasing values.
Authenticators:
- SHOULD implement per credential [=signature counters=]. This prevents the
@@ -6240,15 +6242,17 @@ a numbered step. If outdented, it (today) is rendered as a bullet in the midst o
|credentialRecord|.[$credential record/signCount$]
:|credentialRecord|.[$credential record/signCount$]
:|credentialRecord|.[$credential record/signCount$]
- below in this case, or not, or fails the
- [=authentication ceremony=] or not, is
- [=[RP]=]-specific.