I believe what you have heard relates to a periodic request from Shopify’s banking partners to verify if you have authorization to sell branded products. Just went through this myself and it was pretty straightforward, we simply had to submit copies of invoices for a few of our vendors (brands) and submit a form stating we only sell branded products we have the right to sell. We only buy directly from the brands we represent, so no big issue. Might be different if you don’t have a direct relationship with your branded products.