Empty results array when getting marketing event participations

[AHayer]

Hi,

We have a private app created with the correct scopes (crm.objects.marketing_events.read) however, when we make a GET request to GET /marketing/v3/marketing-events/participations/{marketingEventId}/breakdown we receive the following response

"body": {

"total": 11,

"results": [],

"paging": {

"next": {

"after": "MTA%3D",

"link": "https://api.hubapi.com/marketing/v3/marketing-events/participations/873965935825/breakdown?after=MTA..."

}

}

}

The response confirms we should have 11 results, but the results array is empty so we cannot see the data. If this was a problem with our scopes or permissions, we would expect an error rather than a successful request. If the event ID didnt exist, again, we'd expect an error rather than 11 results with no data

Even more strangely, our request works as expected on one instance of Hubspot, but not on another. It's not clear if there is a difference between the two accounts that would cause this. The apps have the same config and everything else is the same

Has anyone got any suggestions?

[GRajput · Accepted solution]

Hi @AHayer 

Since you mentioned that the API works in one instance but not in the other, I checked the requirements. This API needs the account to have one of the following subscriptions:
1. Content Hub Starter
2. Marketing Hub Free
3. Sales Hub Free
4. Service Hub Free
Please verify whether the other instance has at least one of these.

Also, here’s the link to the official documentation:

https://developers.hubspot.com/docs/api-reference/marketing-marketing-events-v3/basic/get-marketing

I don’t see the GET /marketing/v3/marketing-events/participations/{marketingEventId}/breakdown endpoint listed anywhere in the current docs. It may have been deprecated or could be from an older/unsupported reference. Please double-check the endpoint you're using.

I hope this will help you out. Please mark it as Solution Accepted and upvote to help another Community member.

Thanks!

[AHayer]

I want to add more information to this post after further investigation on our side...

Our private app has multiple scopes, including:

• "crm.objects.marketing_events.read",
• "forms"

With forms i am able to get the following as expected (as expected)
event: `https://api.hubapi.com/marketing/v3/forms/${id}`,
submissions: `https://api.hubapi.com/form-integrations/v1/submissions/forms/${id}`

and for marketing i am able to get the following (as expected)
event: `https://api.hubapi.com/marketing/v3/marketing-events/${id}`,

However, if we make the original call mentioned in my first post `https://api.hubapi.com/marketing/v3/marketing-events/participations/${id}/breakdown`
with "forms" as part of the scope, this is what is returned

"body": {
"total": 355,
"results": [],
"paging": {
"next": {
"after": "MTAw",
"link": "https://api.hubapi.com/marketing/v3/marketing-events/participations/895070438621/breakdown?limit=100..."
}
}
}

if i remove "forms" in the scope, this is what is returned (which is expected)
"body": {
"total": 355,
"results": [
{
"id": "905438932188",
"properties": {
"attendanceState": "NO_SHOW",
"occurredAt": 1762837200000,
"attendanceDurationSeconds": null,
"attendancePercentage": null
},
"associations": {
"contact": {
"contactId": "527901625566",
"email": "emmamartin127@example.com",
"firstname": "Emma",
"lastname": "Martin"
},
"marketingEvent": {
"marketingEventId": "895070438621",
"name": "Scented soaps",
"externalEventId": null,
"externalAccountId": null
}
},
"createdAt": "2025-11-11T05:00:54.127Z"
}...
             "paging": {
"next": {
"after": "MTAw",
"link": "https://api.hubapi.com/marketing/v3/marketing-events/participations/895070438621/breakdown?limit=100..."
}
}]

Why is the forms scope impacting marketing events? Our app needs both for our use case

[STierney]

Hey @AHayer - thanks for posting in the Community!

I'd like to tag in some experts to see what insight they may have regarding this inquiry! @nickdeckerdevs1, @ChrisoKlepke, and @HubSpot_Corey - any suggestions for @AHayer?

Shane, Senior Community Moderator

[AHayer]

I have added an update with some more detail from our investigation. Is there any way we can nudge the experts to provide their opinion?