diff --git a/proposals/xxxx-including-device-keys-with-olm-encrypted-events.md b/proposals/4147-including-device-keys-with-olm-encrypted-events.md
similarity index 98%
rename from proposals/xxxx-including-device-keys-with-olm-encrypted-events.md
rename to proposals/4147-including-device-keys-with-olm-encrypted-events.md
index 3463653c0..4938d4091 100644
--- a/proposals/xxxx-including-device-keys-with-olm-encrypted-events.md
+++ b/proposals/4147-including-device-keys-with-olm-encrypted-events.md
@@ -1,4 +1,4 @@
-# MSCxxxx: Including device keys with Olm-encrypted events
+# MSC4147: Including device keys with Olm-encrypted events
 
 When a Megolm session is sent from one device to another via Olm, the recipient
 can
@@ -128,7 +128,7 @@ came from a deleted device.
 ## Unstable prefix
 
 Until this MSC is accepted, the new property should be named
-`org.matrix.mscxxxx.device_keys`.
+`org.matrix.msc4147.device_keys`.
 
 ## Dependencies