It’s an easy trick: they just check the domains of the email addresses of people who created an account and display the logos of the high profile ones.
Worst case they are going to get a legal email from those companies to remove the logos.
When I worked at one of the large startup company, we all were submitting various websites to our legal department to remove our logo.
I own B2B business, just never felt confident to ask other businesses if that is ok to show theirs logos, so don’t show any. Probably a miss of opportunity.
