Update 40.md

Co-authored-by: Semisol <45574030+Semisol@users.noreply.github.com>

1 files changed, 4 insertions, 2 deletions

diff --git a/40.md b/40.md
index d99aef5..d0174ea 100644
--- a/40.md
+++ b/40.md
@@ -43,8 +43,10 @@ Clients SHOULD ignore events that have expired.
 Relay Behavior
 --------------
 
-Relays SHOULD NOT delete an expired message immediately on expiration. Relays that wish to purge expired messages from their DB should allow for a grace period before deletion. For example, this could be 24h after event expiration.
-Relays MAY choose to not delete expired messages.
+Relays MAY NOT delete an expired message immediately on expiration and MAY persist them indefinitely.  
+Relays SHOULD NOT send expired events to clients, even if they are stored.  
+Relays SHOULD drop any events that are published to them if they are expired.  
+Relays SHOULD persist ephemeral events until their expiration timestamp if an ephemeral event has one, and relays MAY limit the amount of time an ephemeral event is persisted.
 
 Suggested Use Cases
 -------------------