diff --git a/index.html b/index.html
index cd62b54..8b37def 100644
--- a/index.html
+++ b/index.html
@@ -2094,7 +2094,7 @@ <h4>Proof Configuration (Ed25519Signature2020)</h4>
 <a data-cite="VC-DATA-INTEGRITY#PROOF_GENERATION_ERROR">PROOF_GENERATION_ERROR</a>.
               </li>
               <li>
-If |proofConfig|.|created| is set to a value that is not a
+If |proofConfig|.|created| is present and set to a value that is not a
 valid [[XMLSCHEMA11-2]] datetime, an error MUST be
 raised and SHOULD convey an error type of
 <a data-cite="VC-DATA-INTEGRITY#PROOF_GENERATION_ERROR">PROOF_GENERATION_ERROR</a>.