diff --git a/doc/advertising-api.txt b/doc/advertising-api.txt
index 15e64d3..eef98ad 100644
--- a/doc/advertising-api.txt
+++ b/doc/advertising-api.txt
@@ -61,6 +61,23 @@
 			Service Data elements to include. The keys are the
 			UUID to associate with the data.
 
+		dict Data [Experimental]
+
+			Advertising Type to include in the Advertising
+			Data. Key is the advertising type and value is the
+			data as byte array.
+
+			Note: Types already handled by other properties shall
+			not be used.
+
+			Possible values:
+				<type> <byte array>
+				...
+
+			Example:
+				<Transport Discovery> <Organization Flags...>
+				0x26                   0x01         0x01...
+
 		array{string} Includes
 
 			List of features to be included in the advertising