diff --git a/content/client-server-api/modules/end_to_end_encryption.md b/content/client-server-api/modules/end_to_end_encryption.md
index 2729f512..77118ab8 100644
--- a/content/client-server-api/modules/end_to_end_encryption.md
+++ b/content/client-server-api/modules/end_to_end_encryption.md
@@ -1519,6 +1519,8 @@ payload.
 
 ###### Validation of incoming decrypted events
 
+{{% changed-in v="1.15" %}} Existing checks made more explicit, and checks for `sender_device_keys` added.
+
 After decrypting an incoming encrypted event, clients MUST apply the
 following checks: