diff --git a/docs/spec/channel.md b/docs/spec/channel.md
index 6e9b425b3b6..56c44b6aa06 100644
--- a/docs/spec/channel.md
+++ b/docs/spec/channel.md
@@ -182,6 +182,10 @@ Each channel CRD MUST contain an array of subscribers:
 Each channel CRD MUST contain an array of subscribers:
 [`spec.subscribers`](https://github.com/knative/eventing/blob/master/pkg/apis/duck/v1beta1/subscribable_types.go)
 
+Note: The array of subscribers MUST NOT be set directly on the generic Channel
+custom object, but rather appended to the backing channel by the subscription
+itself.
+
 #### Status Requirements
 
 ##### v1alpha1 Status