Hi @Gaurav Jha Thanks for reaching out. If there is no subscription key, the request will be considered anonymous. you can see the user id for the Anonymous users under analytics blade
we do have a rest api call https://learn.microsoft.com/en-us/rest/api/apimanagement/current-ga/user/list-by-service?tabs=HTTP which lists all the user id but it doesn't give any information reg anonymous users.
let me know incase of further queries, I would be happy to assist you.
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