diff --git a/versions/3.0.4.md b/versions/3.0.4.md
index 9bab2e150e..cc53550d85 100644
--- a/versions/3.0.4.md
+++ b/versions/3.0.4.md
@@ -171,6 +171,8 @@ Two formats, `binary` and `byte`, describe different ways to work with binary da
 * `binary` is used where unencoded binary data is allowed, such as when sending a binary payload as an HTTP message body, or as part of a `multipart/*` payload that allows binary parts
 * `byte` is used where binary data is embedded in a text-only format such as `application/json` or `application/x-www-form-urlencoded`
 
+The `maxLength` keyword MAY be used to set an expected upper bound on the length of a streaming payload.  The keyword can be applied to either string data, including encoded binary data, or to unencoded binary data.  For unencoded binary, the length is the number of octets.
+
 Note that the encoding indicated by `byte`, which inflates the size of data in order to represent it as 7-bit ASCII text, is unrelated to HTTP's `Content-Encoding` header, which indicates whether and how a message body has been compressed.
 
 ### <a name="richText"></a>Rich Text Formatting