diff --git a/specification/client_server_api.rst b/specification/client_server_api.rst
index ad58fd1a..948ddc22 100644
--- a/specification/client_server_api.rst
+++ b/specification/client_server_api.rst
@@ -1350,18 +1350,21 @@ State Event Fields
 
 In addition to the fields of a Room Event, State Events have the following fields.
 
-+-----------+--------+-------------------------------------------------------------+
-| Key       | Type   | Description                                                 |
-+===========+========+=============================================================+
-| state_key | string | **Required.** A unique key which defines the overwriting    |
-|           |        | semantics for this piece of room state. This value is often |
-|           |        | a zero-length string. The presence of this key makes this   |
-|           |        | event a State Event. State keys starting with an ``@`` are  |
-|           |        | reserved for referencing user IDs, such as room members.    |
-|           |        | With the exception of a few events, state events set with   |
-|           |        | a given user's ID as the state key MUST only be set by that |
-|           |        | user.                                                       |
-+-----------+--------+-------------------------------------------------------------+
++--------------+--------------+-------------------------------------------------------------+
+| Key          | Type         | Description                                                 |
++==============+==============+=============================================================+
+| state_key    | string       | **Required.** A unique key which defines the overwriting    |
+|              |              | semantics for this piece of room state. This value is often |
+|              |              | a zero-length string. The presence of this key makes this   |
+|              |              | event a State Event. State keys starting with an ``@`` are  |
+|              |              | reserved for referencing user IDs, such as room members.    |
+|              |              | With the exception of a few events, state events set with   |
+|              |              | a given user's ID as the state key MUST only be set by that |
+|              |              | user.                                                       |
++--------------+--------------+-------------------------------------------------------------+
+| prev_content | EventContent | Optional. The previous ``content`` for this event. If there |
+|              |              | is no previous content, this key will be missing.           |
++--------------+--------------+-------------------------------------------------------------+
 
 
 Size limits