diff --git a/docs/source/whatsnew/0.8.4.txt b/docs/source/whatsnew/0.8.4.txt
index 6c493c52..6265a6a1 100644
--- a/docs/source/whatsnew/0.8.4.txt
+++ b/docs/source/whatsnew/0.8.4.txt
@@ -19,6 +19,8 @@ Enhancements
   passed to :class:`~zipline.algorithm.TradingAlgorithm` by the keyword argument
   ``create_event_context`` (:issue:`828`).
 
+* Added `isnan`, `notnan`, and `isfinite` methods to `Factor` (:issue:`861`).
+
 Experimental Features
 ~~~~~~~~~~~~~~~~~~~~~