# List Webinar Participant API return ID as null values **URL:** \ **Category:** Webinars\ **Tags:** api\ **Created:** [March 1, 2023, 11:30am UTC](https://devforum.zoom.us/t/list-webinar-participant-api-return-id-as-null-values/83942 "2023-03-01T11:30:01Z")\ **Posts on this page:** 6\ **Page:** 1
**Author:** ![hninayewai](https://sea2.discourse-cdn.com/flex016/user_avatar/devforum.zoom.us/hninayewai/32/45987_2.png) [@hninayewai](https://devforum.zoom.us/u/hninayewai)\ **Post date:** [March 1, 2023, 11:30am UTC](https://devforum.zoom.us/t/list-webinar-participant-api-return-id-as-null-values/83942/1 "2023-03-01T11:30:01Z")
In [List webinar participant API](https://marketplace.zoom.us/docs/api-reference/zoom-api/methods/#operation/listWebinarParticipants) some of the participant IDs return null values. I have tested with below conditions. Please have a look. Both licensed and unlicensed participants joined webinar respectively. 1. webinar on 2023/02/22. → Return all participants ID 2. webinar on 2023/03/01. → Return ID for licensed participants and null values for unlicensed participants 3.webinar on 2023/03/01. → Return ID for licensed participants and null values for unlicensed participants **※ But return ID for one of the unlicensed participants** I would like to know the behavior of List Webinar Participants API response. Because I need to get a participant ID as unique ID. I haven”t seen that participant ID will return null value in Zoom API documentation. Is it the API issue or something? Furthermore, if you have any ideas to get all participant ID with other way, please assist me. Thanks. ---
**Author:** ![gianni.zoom](https://sea2.discourse-cdn.com/flex016/user_avatar/devforum.zoom.us/gianni.zoom/32/32523_2.png) [@gianni.zoom](https://devforum.zoom.us/u/gianni.zoom)\ **Post date:** [March 1, 2023, 10:39pm UTC](https://devforum.zoom.us/t/list-webinar-participant-api-return-id-as-null-values/83942/3 "2023-03-01T22:39:59Z")
Hi @hninayewai , Please see below. It may be related to the changes outlined here: > [@Meeting participants report not returning IDs for participants](https://devforum.zoom.us/t/meeting-participants-report-not-returning-ids-for-participants/83893/5): > > @brian8 responding here since this is a wide-spread behavior. It seems there were some API changes made where this info will not be returned unless the participants are on the dev’s account. I’m still awaiting more information, but here is the most recent change log release: [https://devsupport.zoom.us/hc/en-us/articles/13573564717581-Zoom-Meeting-API-February-25-2023](https://devsupport.zoom.us/hc/en-us/articles/13573564717581-Zoom-Meeting-API-February-25-2023) Even though `GET /past_webinars/{webinarId}/participants` is not listed as affected in the change log, it may have been. We’re awaiting more info. Thanks, Gianni ---
**Author:** ![hninayewai](https://sea2.discourse-cdn.com/flex016/user_avatar/devforum.zoom.us/hninayewai/32/45987_2.png) [@hninayewai](https://devforum.zoom.us/u/hninayewai)\ **Post date:** [March 2, 2023, 1:07am UTC](https://devforum.zoom.us/t/list-webinar-participant-api-return-id-as-null-values/83942/4 "2023-03-02T01:07:37Z")
@gianni.zoom Thanks for your reply. So, do you mean we have to wait until the changelog is published? If so, may I know ①how long it would take to be published? ②probably, this API `GET /past_webinars/{webinarId}/participants` also have effect for bug fixing? ---
**Author:** ![gianni.zoom](https://sea2.discourse-cdn.com/flex016/user_avatar/devforum.zoom.us/gianni.zoom/32/32523_2.png) [@gianni.zoom](https://devforum.zoom.us/u/gianni.zoom)\ **Post date:** [March 6, 2023, 4:00am UTC](https://devforum.zoom.us/t/list-webinar-participant-api-return-id-as-null-values/83942/5 "2023-03-06T04:00:12Z")
Hi @hninayewai , You don’t have to wait for the changelog! It looks like participant id will not be returned for users who are external to the host account, but registrant id will be available. You will need to require registration to get this value. ---
**Author:** ![gianni.zoom](https://sea2.discourse-cdn.com/flex016/user_avatar/devforum.zoom.us/gianni.zoom/32/32523_2.png) [@gianni.zoom](https://devforum.zoom.us/u/gianni.zoom)\ **Post date:** [March 8, 2023, 8:17pm UTC](https://devforum.zoom.us/t/list-webinar-participant-api-return-id-as-null-values/83942/6 "2023-03-08T20:17:34Z")
Update: here is the release on this made last Friday, March 3: [https://marketplace.zoom.us/docs/guides/stay-up-to-date/announcements/#meeting-api-fields-hidden-in-dashboard-and-report-apis](https://marketplace.zoom.us/docs/guides/stay-up-to-date/announcements/#meeting-api-fields-hidden-in-dashboard-and-report-apis) ---
**Author:** ![gianni.zoom](https://sea2.discourse-cdn.com/flex016/user_avatar/devforum.zoom.us/gianni.zoom/32/32523_2.png) [@gianni.zoom](https://devforum.zoom.us/u/gianni.zoom)\ **Post date:** [March 8, 2023, 8:19pm UTC](https://devforum.zoom.us/t/list-webinar-participant-api-return-id-as-null-values/83942/7 "2023-03-08T20:19:04Z")
See also: [IMPORTANT notice about reporting endpoints and participant identifiers in the Meeting API](https://devforum.zoom.us/t/important-notice-about-reporting-endpoints-and-participant-identifiers-in-the-meeting-api/84330)