This week's biggest stories span a customs agency asking importers to map their own supply chains, a regulator alleging Amazon quietly rewrote the rules of its own ad auctions, and the UK finally getting the trade deal it signed three years ago. One is a compliance warning with a December deadline, one is a billion-dollar legal fight over trust, and one is a reminder that new trade access rarely closes an old gap. Here is what happened and why each one matters for sourcing, retail and supply chain teams.

CBP's 64 Questions: Why the New Supply Chain Disclosure Rule Could Reach Your Tier Three Suppliers

CBP has not written a new rule yet, but it has told the entire import industry exactly where it is looking: foreign export paperwork, the identities of manufacturers and distributors behind every shipment, and whether importers should be on the hook for suppliers they've never directly dealt with. Comments close 1st December, and law firms are already telling clients that data "from entities several tiers removed from the importer" could become the new baseline. We dig into the 64 questions, the pushback from trade groups, and what to do before the deadline.

FTC v. Amazon: How a Secret 'Soft Reserve Price' Turned Ad Auctions Into a $20 Billion Problem

The FTC and 22 states allege Amazon spent seven years telling advertisers they were in a fair second-price auction while quietly charging a hidden markup an internal document called a "surcharge." New York's attorney general puts the overcharge at more than $20 billion since 2019, affecting over a million advertisers. Amazon calls the suit "misguided" and says it will fight in court. We break down the mechanics of the alleged scheme, Amazon's defense, and what it means for anyone who advertises on the platform.

UK Gains Full CPTPP Access: What the £12.9 Trillion Trading Bloc Really Means for Sourcing and Manufacturing

Canada's ratification brought the UK's five-year CPTPP journey to a close on September 1, giving British exporters zero-tariff access to more than 99% of current goods exports across all 11 other member countries at once. The government is calling it a £12.9 trillion opportunity; the House of Commons Library's own analysis puts the long-run GDP gain at a much more modest £2 billion. We look at what actually changed, the cumulation rules worth knowing about, and why critics say it doesn't come close to plugging the Brexit gap.

That's this week's top three. Hit reply and let us know which of these you want us to keep tracking.