This page is part of the Subscriptions R5 Backport (v1.1.0: STU 1.1) based on FHIR v4.3.0. This is the current published version.  For a full list of available versions, see the Directory of published versions 
This Bundle provides an example of an empty notification.  This Bundle is typical of what may be posted to a notification endpoint (e.g., a listening HTTP server, etc.).
Bundle r4-notification-empty of type history
Entry 1 - fullUrl = urn:uuid:9e41ff6d-5be6-4e6a-8b85-abd4e7f58400
Request:
GET https://example.org/fhir/Subscription/admission/$status
Response:
200
Resource Parameters:
Parameters
subscription https://example.org/fhir/Subscription/admission topic http://hl7.org/SubscriptionTopic/admission status active type event-notification events-since-subscription-start 2 notification-event event-number 2 timestamp 2020-05-29 11:44:13-0500 
In order to satisfy the requirements of a history Bundle (specifically bdl-3 and bdl-4), note that Bundle.entry.request must exist.
For the status resource (entry[0]), the request is filled out to match a request to the $status operation.
Since this is an empty notification and does not include additional entries, no additional constraints are imposed by Bundle requirements.