Hi
As mentioned by Scott, there are no such user restriction.
Reference article:- http://adobeaemclub.com/max-number-of-users-in-cq-publisher/
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Question: We are planning to have a CQ publisher around 65k users & around thousand groups. Will there be any performance issues & do we have any limit on number of users you can have in publisher.
Answer: There is no restriction as such. But if you have your users already outside, you can also have your own external login module for authentication and authorization. You will, however, want to ensure you are using AEM 6.0 or higher and Oak. With Jackrabbit/CRX 2, such scale was possible, but you do need to do some extra configuration if you have groups with thousands of members. Your post didn’t call this out specifically, but if you have tens of thousands of users, odds are you have some big groups
I hope this would be helpful to you.
Thanks and Regards
Kautuk Sahni