diff --git a/versions/3.1.0.md b/versions/3.1.0.md
index 39425bd6b9..9f89948340 100644
--- a/versions/3.1.0.md
+++ b/versions/3.1.0.md
@@ -3253,6 +3253,20 @@ scheme: bearer
 bearerFormat: JWT
 ```
 
+###### MutualTLS Sample
+
+```json
+{
+  "type": "mutualTLS",
+  "description": "Cert must be signed by example.com CA"
+}
+```
+
+```yaml
+type: mutualTLS
+description: Cert must be signed by example.com CA
+```
+
 ###### Implicit OAuth2 Sample
 
 ```json