diff --git a/20.md b/20.md
index 9a96f6df..8bd7ab57 100644
--- a/20.md
+++ b/20.md
@@ -21,7 +21,7 @@ The `message` SHOULD provide additional information as to why the command succee
 
 The `message` SHOULD start with `blocked:` if the pubkey or network address has been blocked, banned or is not on a whitelist.
 
-The `message` SHOULD start with `invalid:` if the event doesn't meet some specific criteria (created_at is too far off, etc)
+The `message` SHOULD start with `invalid:` if the event is invalid or doesn't meet some specific criteria (created_at is too far off, id is wrong, signature is wrong, etc)
 
 The `message` SHOULD start with `pow:` if the event doesn't meet some proof-of-work difficulty. The client MAY consult the relay metadata at this point to retrieve the required posting difficulty.
 
@@ -29,7 +29,7 @@ The `message` SHOULD start with `rate-limited:` if the event was rejected due to
 
 Ephemeral events are not acknowledged with OK responses, unless there is a failure.
 
-If the event is malformed and could not be parsed, a NOTICE message SHOULD be used instead of a command result.
+If the event or `EVENT` command is malformed and could not be parsed, a NOTICE message SHOULD be used instead of a command result. This NIP only applies to non-malformed EVENT commands.
 
 
 Examples