How to find unauthorized sellers, and cut off their supply

An unauthorized seller is a storefront advertising your product that you have no supply relationship with. Finding them is the easy half: compare every seller observed in the channel against your authorized reseller list and the remainder are your problem. The hard half is that their inventory came from somewhere, almost always from one of your own accounts, and until you find that account you are removing listings while the supply keeps flowing.

Where unauthorized sellers get their inventory

Nobody manufactures your product except you. Every unit an unauthorized seller lists arrived through a route you control, and there are only a handful of routes. Naming them narrows the investigation from the whole internet to a shortlist of accounts.

How to find unauthorized sellers in your channels

The method is subtraction. Observe every seller advertising your products, resolve each to a legal entity, and subtract the ones on your authorized list. What remains is the working set. The difficulty is entirely in the resolution step, because storefront names are cheap and change often.

1. 1Build the observed-seller set. Sweep the marketplaces and retail sites where your products appear and record every seller name attached to an offer, per SKU, with the date. Do it on a schedule, because sellers appear and vanish between sweeps. This is the same collection loop described in how to monitor MAP violations.
2. 2Resolve names to entities. Marketplace seller profiles usually carry a business name and address. Group storefronts that share a business name, an address, a phone number or a distinctive returns address into one entity.
3. 3Subtract the authorized list, including aliases. Your list has to hold every storefront name each account trades under, or authorized sellers will keep showing up as unknowns and the working set will be noise.
4. 4Rank the remainder by exposure, not by annoyance. Score each unknown seller on breadth of your catalogue listed, apparent stock depth, how far below MAP it advertises, and how long it has persisted. A seller carrying 40 of your SKUs in depth is a supply problem. One seller with two units of a discontinued item is not worth an investigation.
5. 5Look at the pattern, not the individual. If eleven unknown storefronts appeared in the same six weeks, carry the same nine SKUs, and sit within a couple of dollars of each other, they are supplied from one place. That pattern is the most useful thing the observation step produces.

Signals that tell you what kind of seller you are looking at

• Catalogue breadth. Broad and deep coverage of one brand means a supply line. A scattering of unrelated brands means arbitrage or a liquidation buyer.
• Stock depth over time. A seller who restocks a SKU after every sell-out has a repeatable source. One who lists 3 units and disappears bought a pallet.
• Price behaviour. A steady price a fixed percentage under everyone else suggests a known landed cost. Erratic pricing suggests inventory of unknown origin being cleared.
• Listing origin. Whether the seller created the listing or attached an offer to an existing one tells you how organised the operation is.
• Timing. New storefronts appearing shortly after a big allocation, a promotion or a quarter-end rebate window point directly at what to look at internally.
• Condition and packaging language. Wording about no manufacturer warranty, plain packaging or bulk packed is a strong hint of returns, salvage or export stock.

Test buys and lot-code tracing

Observation identifies who is selling. A test buy identifies where the unit came from. This is the step most brands skip, and it is the only one that converts an unauthorized seller from a nuisance into an actionable internal finding.

1. 1

   1. Buy through a neutral identity

   Order using an address and payment method not obviously connected to the brand. A test buy delivered to your head office teaches the seller which SKUs to stop shipping to you and nothing else. Buy the specific SKU and quantity that matches the pattern you are investigating.

2. 2

   2. Preserve everything on arrival

   Photograph the shipping label, the outer carton, the inner packaging and the product before anything is opened. Keep the packing slip, the invoice and any warranty insert. Log the order date, the seller name, the price paid and the tracking number against the case.

3. 3

   3. Record every identifier on the unit

   Lot code, batch number, serial number, date code, carton number and any warehouse or distributor label still attached. Identifiers get printed in different places on different SKUs, so write down where you found them; the next person doing this will need it.

4. 4

   4. Match identifiers to your shipment records

   This is the moment of truth. A lot code maps to a production run, and a production run maps to the shipments it went into. If your systems can resolve a lot to a customer, you have named the leaking account. If they cannot, that gap is now the most valuable thing this investigation found.

5. 5

   5. Corroborate before you act

   One unit is a data point. Two or three buys from the same seller, or from different sellers in the same cluster, resolving to the same account is a finding. Brands have been embarrassed by acting on a single lot code that turned out to have been split across three customers.

6. 6

   6. Act on the account, not the storefront

   Take the finding to the account: the evidence, the lot trace, and the terms they agreed. Options run from a warning and tighter allocation, through removing volume rebates, to terminating supply. Whatever you choose, the storefront stops being restocked, which is the outcome you were after.

Worked example, illustrative. Suppose twelve unknown storefronts are advertising a $199.00 product, and reporting each listing takes a couple of hours and gets undone when the seller relists under a new name. Six test buys at $199.00 plus shipping is roughly $1,250 of inventory, most of it recoverable, and the lot codes point at two distributor accounts. Closing those two accounts removes the supply behind every storefront they were feeding. That is the argument for tracing over reporting.

Marketplace reporting routes, and what they actually enforce

It helps to be blunt. Marketplaces do not enforce your pricing policy. A report saying this seller is below our MAP will be closed without action, because MAP is an arrangement between a brand and its resellers and the marketplace is not a party to it.

What marketplaces do enforce is rights. Most large marketplaces run a rights-owner program, such as Amazon's Brand Registry or eBay's Verified Rights Owner program, through which a brand can report listings that infringe a trademark or copyright, misuse brand imagery or product copy, misrepresent condition, or offer counterfeit goods. Those routes get results, and they get a brand into trouble when misused.

Closing the leak upstream

Every durable fix is a change to the terms you sell on or to how you allocate. None of them is a monitoring feature, which is exactly why so many brands buy monitoring and stay frustrated.

• Write no-diversion terms into distribution agreements. Name the permitted customer classes, territories and channels, and include audit rights over sales-out reporting. Terms with no audit right are aspirations.
• Require sales-out reporting. A distributor who reports what it sold and to whom is a distributor whose diversion becomes arithmetic instead of suspicion.
• Restructure rebates toward sell-through. Rebates keyed to purchase volume actively fund overbuying, which is the most common diversion route on the table above.
• Control liquidation contractually. Say what happens to overstock, returns and discontinued goods, including whether they may be resold as new and in what markets.
• Differentiate regional SKUs. Distinct model numbers, packaging or firmware make diverted units visible and make the material-difference argument, if you ever need it, easier to make.
• Serialise, at least by carton. Lot-to-customer mapping is the difference between a test buy that names an account and a test buy that produces a shrug.
• Publish and maintain an authorized reseller list. It tells buyers who is legitimate, and it gives you a clean subtraction step every time you sweep the channel. The MAP policy template covers how the policy should reference it.

The metric that tells you it is working

Count the share of observed sellers not on your authorized list, and track it monthly. Illustrative arithmetic: if 34 of 90 observed sellers are unknown, unauthorized share is 37.8 percent. Listings removed is a vanity number that rises whether you are winning or losing. Unauthorized share falls only when supply is closing, and it is the number to put in front of the leader who has to approve terminating a profitable account.

Run it alongside the MAP measures: compliance rate, median time to cure and repeat-offender share. If compliance is fine among named accounts and terrible overall, the problem is diversion rather than pricing discipline, and the fix sits in your distribution terms rather than a better letter. Background on what a policy can reach is in what MAP pricing is, and the detection loop is in MAP monitoring software.