diff --git a/.ion-connect-protocol/ICIP-3000.md b/.ion-connect-protocol/ICIP-3000.md
index 3afb1ac..b20260c 100644
--- a/.ion-connect-protocol/ICIP-3000.md
+++ b/.ion-connect-protocol/ICIP-3000.md
@@ -91,6 +91,8 @@ If the community is `closed`, then an `authorization` tag MUST be added to the e
 }
 ```
 
+Leaving a community is done by deleting the joining event (kind `1750`) via a generic [kind 9](https://github.com/nostr-protocol/nips/blob/master/09.md) deletion request.
+
 # Posting to a community
 
 Kind `1` or `30023` events can be posted to a community. 
diff --git a/.ion-connect-protocol/ICIP-51.md b/.ion-connect-protocol/ICIP-51.md
new file mode 100644
index 0000000..0e45993
--- /dev/null
+++ b/.ion-connect-protocol/ICIP-51.md
@@ -0,0 +1,58 @@
+ICIP-51
+======
+
+Lists
+-----
+
+`draft` `optional`
+
+This ICIP extends [NIP-51](https://raw.githubusercontent.com/nostr-protocol/nips/refs/heads/master/51.md) with
+additional lists and sets.
+
+## Standard lists
+
+| name                         | kind  | description                                                                                                                            | expected tag items                                                                                                                                             |
+|------------------------------|-------|----------------------------------------------------------------------------------------------------------------------------------------|----------------------------------------------------------------------------------------------------------------------------------------------------------------|
+| On-Behalf of (Delegation)    | 10100 | [ICIP-2000](ICIP-2000.md) attestations list                                                                                            | `"p"` (pubkeys, with [ICIP-2000](ICIP-2000.md) attestation string)                                                                                             |
+| Chats (including E2EE chats) | 11750 | [ICIP-3000](ICIP-3000.md) communities or [NIP-17](https://github.com/nostr-protocol/nips/blob/master/17.md) chats the user is apart of | `"h"` (kind:`31750` community definitions); encrypted `p` and `subject` tags for [NIP-17](https://github.com/nostr-protocol/nips/blob/master/17.md) E2EE chats |
+
+## Sets
+
+| name | kind | description | expected tag items |
+|------|------|-------------|--------------------|
+|      |      |             |                    |
+
+## Examples
+
+### An attestation _list_ with some delegated pubkeys
+
+```json
+  {
+  "kind": "10100",
+  "tags": [
+    ["p", "477318cfb5427b9cfc66a9fa376150c1ddbc62115ae27cef72417eb959691396", "", "active:1674834236:1,7"]
+  ],
+  "content": "",
+  ...
+}
+```
+
+### A _list_ of all communities an user is in
+
+```json
+{
+  "kind": 11750,
+  "tags": [
+    ["h", "01938730-22ea-7829-b705-c61463c8edeb"],
+    ["h", "01938730-5ca3-7897-99b2-fb6fbadb6156"],
+    ["encrypted"]
+  ],
+  "content": nip44_encrypt([
+      [ "p", "one-on-one receiver pubkey1" ],
+      [ "p", "one-on-one receiver pubkey2" ],
+      [ "subject", "family & friends", "receiver1 pubkey", "receiver2 pubkey", "receiver3 pubkey"],
+      [ "subject", "work", "receiver1 pubkey", "receiver2 pubkey",... "receiver25 pubkey"]
+    ]),
+  ...
+}
+````
diff --git a/.ion-connect-protocol/README.md b/.ion-connect-protocol/README.md
index 0a5a842..e09829f 100644
--- a/.ion-connect-protocol/README.md
+++ b/.ion-connect-protocol/README.md
@@ -6,8 +6,9 @@
 
 ## protocol changes
 
-| ICIPs/NIPs | Change Type | NOSTR NIPs Pull Request                                  | comments                                                                           |
-|------------|-------------|----------------------------------------------------------|------------------------------------------------------------------------------------|
-| ICIP-1000  | Addition    | [1522](https://github.com/nostr-protocol/nips/pull/1522) |                                                                                    |
-| ICIP-2000  | Addition    | [1482](https://github.com/nostr-protocol/nips/pull/1482) |                                                                                    |
-| ICIP-3000  | Addition    |                                                          | an extension of [NIP-72](https://github.com/nostr-protocol/nips/blob/master/72.md) |
+| ICIPs/NIPs | Change Type  | NOSTR NIPs Pull Request                                  | comments                                                                           |
+|------------|--------------|----------------------------------------------------------|------------------------------------------------------------------------------------|
+| ICIP-1000  | Addition     | [1522](https://github.com/nostr-protocol/nips/pull/1522) |                                                                                    |
+| ICIP-2000  | Addition     | [1482](https://github.com/nostr-protocol/nips/pull/1482) |                                                                                    |
+| ICIP-3000  | Addition     |                                                          | an extension of [NIP-72](https://github.com/nostr-protocol/nips/blob/master/72.md) |
+| ICIP-51    | Modification |                                                          | an extension of [NIP-51](https://github.com/nostr-protocol/nips/blob/master/51.md) |