Amazon could end up being required to declare the seller’s information to the buyer (at time of purchase!), and required to validate that information using expensive non-trivial practices such as business license lookups and tax form SSN/EIN checks. This court decision implies that liability defaults to Amazon under their current practices, and shifting that liability would need to involve disclosure prior to sale. These are all absolutely market-destroying things - and when you apply them to eBay, which does not provide seller contact information or perform tax validation before the sale occurs, it only worsens in potential impact for businesses profiting off of their enforcement-free approach today.