Mixpanel itself does not provide a built-in mechanism to only fire (send) an event if a specific property is set. The Mixpanel SDKs and APIs allow you to track events and include properties, but the logic to determine whether an event should be sent based on the presence of a property must be implemented in your application code before calling the Mixpanel tracking function.
For example, you would check if the property exists or has a value in your code, and only then call mixpanel.track() or the equivalent method in your SDK. There is no mention in the knowledge sources of a Mixpanel-side configuration or filter that prevents an event from being sent if a property is missing.
However, once events are tracked, Mixpanel provides robust filtering capabilities in reports and analyses. You can filter events by property values in reports, funnels, and queries, but this happens after the event has already been ingested by Mixpanel, not before it is sent or recorded Reports Overview.
In summary:
You must implement the logic to only fire an event when a property is set within your own application code. Mixpanel does not natively block or conditionally send events based on property presence.
