If I want to enroll another brand's trademark on my account as an admin on their behalf, what documentation does Amazon require?

Sell On Amazon General Selling on Amazon Questions
1

I’m already familiar with the process and paperwork needed for registering my own trademark.

Thanks!

2

Never done this, but from what I know, the company needs to register their brands in Amazon Brand Registry and then assign you the role.

3

You need a Letter of Authorization from the brand owner.