diff --git a/draft-ietf-oauth-attestation-based-client-auth.md b/draft-ietf-oauth-attestation-based-client-auth.md
index e539cd3..1389176 100644
--- a/draft-ietf-oauth-attestation-based-client-auth.md
+++ b/draft-ietf-oauth-attestation-based-client-auth.md
@@ -325,7 +325,7 @@ To validate an HTTP request which contains the client attestation headers, the r
 2. There is precisely one OAuth-Client-Attestation-PoP HTTP request header field, where its value is a single well-formed JWT conforming to the syntax outlined in [](#client-attestation-pop-jwt).
 3. The signature of the Client Attestation PoP JWT obtained from the OAuth-Client-Attestation-PoP HTTP header verifies with the Client Instance Key contained in the `cnf` claim of the Client Attestation JWT obtained from the OAuth-Client-Attestation HTTP header.
 
-An error parameter according to Section 3 of {{RFC6750}} SHOULD be included to indicate why a request was declined. If the Client Attestation is absent or not using an expected server-provided challenge, the value `use_attestation_challenge` can be used to indicate that an attestation with a server-provided challenge was expected. If the attestation and proof of possession was present but could not be successfully verified, the value `invalid_client_attestation` is used.
+An error parameter according to Section 3 of {{RFC6750}} SHOULD be included to indicate why a request was declined. If the Client Attestation is not using an expected server-provided challenge, the value `use_attestation_challenge` can be used to indicate that an attestation with a server-provided challenge was expected. If the attestation and proof of possession was present but could not be successfully verified, the value `invalid_client_attestation` is used.
 
 ## Client Attestation at the Token Endpoint {#token-endpoint}
 
@@ -625,6 +625,8 @@ This section requests registration of the following scheme in the "Hypertext Tra
 --- back
 
 # Document History
+-07
+* do not use error response `use_attestation_challenge` on absent client attestation
 
 -06
 
@@ -692,6 +694,7 @@ Filip Skokan,
 Francesco Marino,
 Guiseppe De Marco,
 Kristina Yasuda,
+Micha Kraus,
 Michael B. Jones,
 Takahiko Kawasaki
 and