Confidentiality concerns: Does brand administrator have access to my data

if it is anonymous link, you can not until you ask name, email in survey.

But in case you are sending survey via email with contact list, you can see wo answered what and you can control survey permissions in way , you can only see data.

I couldn’t see anything conclusive in the help/ previous community posts to answer your question - but I could be wrong.I think it’s best to check with Qualtrics support as to whether the Brand Administrator has access or not (either directly or through an API). Sorry, I couldn’t be more help.

I believe that with an anonymous link, the brand admin would be able to see the survey and data but there would be no personal information for the respondents attached to it (unless you ask for name, email, phone or something in the survey itself).  

Brand Administrators can proxy login as any user in the brand. They can theoretically see and do anything that your user can. They would have to be pretty deliberate to login as your user and review any survey data though, so unless they had a reason to do so you should be okay. 

I love all the above answers. One thing I would add is that there is a setting to disable proxy logins in the Security Tab. A brand admin would be the one that has access to disable this, but it would make it so they cannot access your survey. Of course, because of the Brand Admin access, they could toggle this back on. Ultimately, it would be best to ensure they are on the same page as you with data privacy and the integrity of data you are collecting.