diff --git a/README.md b/README.md
index f4ce541..b2ad79e 100644
--- a/README.md
+++ b/README.md
@@ -47,6 +47,7 @@ API documentation is available [here](https://bitchan.github.io/bitmessage/docs/
   - [x] pubkey
   - [x] msg
   - [x] broadcast
+  - [ ] ACK data generation
 - [x] WIF
 - [x] POW
 - [x] High-level classes