Quick answer. An inauthentic complaint on Amazon is rarely random. It usually starts in one of seven places, namely the words a buyer used in a complaint or return, a condition or packaging gap, sourcing you cannot prove with invoices, a rights owner’s test buy, commingled units from before Amazon ended commingling on March 31, 2026, a returned unit that went back on the shelf, or a listing that does not match the product. Amazon’s Anti-Counterfeiting policy says you must provide records about authenticity when asked, and documents may only be edited to remove pricing. To prevent complaints, control each birthplace with verified suppliers, a receiving check, matched listings, inspected returns and Amazon barcodes on reseller inventory. To diagnose one that arrived, trace it back to the order, the unit and the source.

Most sellers meet the word “inauthentic” in an Account Health notice, after the damage is done, and the reflex is to send every invoice in the drawer. If the complaint was born from a returned unit with a broken seal, or from an old shipment mixed with another seller’s stock, a pile of invoices answers a question Amazon did not ask, and the same complaint comes back a month later.

This is episode four of our series on root cause analysis. For the basics, our guide to what an inauthentic suspension is covers the policy and the appeal, and our comparison of inauthentic and counterfeit complaints explains how the two differ. This episode traces how a complaint is born, ties each birthplace to a root cause you can name, and shows how to shut each one before the next complaint arrives.

How an inauthentic complaint is born

An inauthentic complaint means Amazon cannot confirm a product is genuine, which is a lower bar than proof of a fake. A genuine product can draw one if its packaging, history or paperwork made someone doubt it.

Amazon’s Anti-Counterfeiting policy says Amazon works with manufacturers, rights holders, content owners, vendors and sellers to detect inauthentic products, removes suspect listings based on its own review, and encourages rights owners with authenticity concerns to notify it. The signal can come from a buyer, a rights owner or Amazon itself. Behind each one sits a physical or paper cause in your business.

Three messengers, seven birthplaces

The messenger is who raised the flag. The birthplace is what in your operation gave them a reason to. Answer only the messenger and the complaint returns. Fix the birthplace and it stays fixed.

What Amazon can do once the flag is up

The policy is direct about consequences. If you sell inauthentic products, Amazon says it may immediately suspend or terminate your selling account and any related accounts, dispose of inauthentic products in its fulfillment centers at your expense, and withhold payments. You must also provide records about the authenticity of your products if Amazon requests them. That last line is why every root cause here ends in a document question. Can you show, on paper, where this unit came from and what happened to it?

This is educational information, not legal advice. Authenticity and trademark disputes carry legal risk, and a seller facing a rights owner’s legal claim should speak with qualified counsel.

Reading the buyer’s words

When a buyer is the messenger, their wording is the first clue. Buyers write what they saw, smelled or felt, and you translate that into a physical cause.

Pull every buyer touchpoint for the ASIN over the last several months, including buyer messages, return comments, reviews and any A-to-z claim text. Search them for words like fake, knockoff, not real, different, smells, used, opened, resealed, missing, old and expired. Then sort what you find by theme.

Do not argue with the wording, measure it

Amazon’s FBA customer returns policy notes that the return reason a buyer selects comes from a standard list and may not reflect the true circumstances. The same caution applies in reverse. A buyer who writes “fake” may be describing a broken seal. Treat the words as a pointer to where you look, not a verdict. Count how many complaints share a theme and in what date window.

Condition and packaging gaps

What “New” means on Amazon

Amazon’s Condition guidelines define New as a brand-new item, with the original manufacturer’s warranty, if any, still applying, and original packaging present for most New items, though certain items like shoes may be re-boxed. List something as New that does not meet that standard and you have created the doubt yourself.

Conditions Amazon will not accept at all

The same page lists items that are unacceptable for listing, and several map straight onto authenticity complaints.

• An item not created by the original manufacturer or copyright holder, including copies, counterfeits, replicas and imitations.
• An item originally distributed as a promotional copy, promotional bundle or product sample.
• An item past its expiration date, with an unacceptable portion of its shelf life remaining, or where the expiration date has been tampered with or removed.
• An item intended for destruction or disposal, or designated as unsellable by the manufacturer, a supplier, a vendor or a retailer.

The last two matter more than sellers expect. Liquidation lots, salvage stock and “closeout” pallets sometimes contain goods a retailer or manufacturer marked as unsellable. The units may be genuine and still unacceptable for sale, and the buyer who gets one writes “this does not look real.”

Packaging you changed on purpose

Repacking, over-boxing or labeling over brand labels is often ordinary prep. It becomes a root cause when it hides or damages something buyers use to judge authenticity, such as a seal, a lot code or the brand’s label. An FNSKU label stuck over a lot code removes the one mark that shows which batch the unit came from.

Sourcing you cannot verify

Every other birthplace is easier to answer when sourcing is clean, and none can be fully answered when it is not.

What Amazon asks for

Amazon’s Intellectual Property policy says that for trademark or counterfeit concerns on the product or packaging, you can provide an invoice or order ID through the Account Health Dashboard that demonstrates authenticity. For multiple warnings, it lists invoices proving authenticity (you may remove pricing), Amazon order IDs demonstrating authenticity, an authorization letter from the rights owner (which cannot be a forwarded email), or a court order. The Anti-Counterfeiting policy draws a hard line. You may remove pricing information from these documents, but documents edited in any other way, or that are misleading, are a violation and lead to enforcement.

Apply that rule the day you buy, not the day you are flagged. If the supplier cannot give you an invoice that names both businesses, the product and the quantity, the root cause of your future complaint already exists. Our guide on keeping invoices to Amazon’s standard covers the document itself in depth.

Three sourcing patterns that breed complaints

• Retail and online arbitrage. A store receipt shows a purchase, not a supply chain back to the brand.
• A supplier you cannot independently confirm. If the business name on the invoice is not in a state business registry, or the address and phone number lead nowhere, a reviewer who checks will find the same.
• Volume that does not reconcile. Invoices for 300 units when you sold 1,100 leave 800 units with no documented origin. A genuine gap is still a gap.

Verify the supplier before the first order

Two free public checks help. The National Association of Secretaries of State links to each state’s business registration pages and corporate name databases, so you can confirm the supplier’s legal name and status match the invoice. The USPTO’s Trademark Search system, with status and documents in its Trademark Status and Document Retrieval site, shows who owns the brand’s mark, and so who a letter of authorization would have to come from.

Rights owner test buys

Brands watch their listings. A common way for a rights owner to check a reseller is to place an order, inspect the unit and compare it with genuine stock. Amazon’s policy encourages rights owners with authenticity concerns to notify it, and says it will investigate. When a test buy is the messenger, the birthplace is whatever the brand saw in that one unit, or in your status as a seller.

What a test buy tends to catch

A test buy tends to catch an older or regional packaging version, a lot or serial code the brand did not ship to your region, missing inserts or warranty cards, or a code covered or damaged during your own prep. Sometimes it catches nothing physical at all, only a reseller the brand has not authorized.

That last case is the hardest. A brand that objects to unauthorized resale may describe it in authenticity terms. You answer it with invoices that trace your units to a legitimate source and, where the brand restricts its distribution, with a decision about whether to keep selling that brand at all. Our article on the dangers of selling unauthorized brands covers that decision.

The rights owner retraction path

The Intellectual Property policy says that if you have a license or other agreement that lets you use the IP in a notice, you can contact the rights owner who filed the complaint and request a retraction, and your content may be reinstated if Amazon receives one. That route exists only when the relationship is real and documented, which is another reason to keep supplier and brand correspondence on file from the first order.

Commingling, and what changed on March 31, 2026

Amazon’s FBA Barcode Choice and Labeling FAQ defines commingling as Amazon fulfilling customer orders with exact product matches from the closest available inventory, even if that inventory belonged to a different seller. If another seller’s unit of the same product was not genuine and it shipped against your order, the complaint landed on you.

The new rule

Amazon says FBA barcode requirements changed as of March 31, 2026. Brand owners can keep using manufacturer barcodes without stickers. Resellers, including authorized resellers, must now use Amazon barcodes even when the product has a manufacturer barcode. Amazon says this means customers who buy from you only receive products from your inventory, including returns and removals.

To use manufacturer barcodes, Amazon’s eligibility page says a product must be in new condition, carry a single scannable UPC, EAN or ISBN matching a single ASIN, and belong to a brand enrolled in Brand Registry where the seller is a brand representative. Products with a GTIN exemption still need Amazon barcodes.

Why commingling is still a root cause to check

Amazon’s FAQ says no action is required for reseller stickerless inventory that was in transit to or stored in fulfillment centers before March 31, 2026, and those products keep selling under their original SKUs. All new shipments created after that date must use Amazon barcodes. If a complaint arrives on an order that shipped from older stickerless stock, commingling can still be the birthplace. If the order shipped from labeled inventory created after the change, look elsewhere.

Amazon also treats inventory received from resellers without Amazon barcodes after that date as defective, and units not labeled in compliance are not eligible for reimbursement. A reseller who skips labels now creates inventory that is harder to trace in an authenticity case and that Amazon will not reimburse.

Returns that went back on the shelf

Returns are the quietest birthplace. A buyer opens a unit and sends it back, it is judged sellable, and the next buyer gets a unit that does not look new.

How returns re-enter FBA inventory

Amazon’s FBA customer returns policy says Amazon evaluates each returned item and puts sellable ones back into your sellable inventory. An item is unsellable when it is not in the same condition as listed, is defective, damaged, opened or lacking required labeling, or may pose a health or safety risk. For items categorized as Defective or Customer damaged, you must submit a removal order within 30 days after the return arrives at the fulfillment center, and you can ask Amazon to return or dispose of unsellable inventory automatically.

That judgment is made unit by unit, without knowing which details your buyers use to judge authenticity. Where a broken seal or missing insert reads as fake, a returned unit is a risk.

How to see which returns came back

Amazon says the License Plate Number (LPN) label on a returned item lets you find it in the FBA customer returns report, though this may not work if you track inventory with manufacturer barcodes. Line up return dates against later complaint dates. If complaints cluster after a run of returns for the same SKU, you have a candidate birthplace. For merchant fulfilled orders, your own returns log is the equivalent record, and it exists only if someone keeps it.

Listings that do not match the product

The last birthplace is on the screen. If the detail page shows a different package, count, model or accessories, the buyer concludes the item is not the real thing.

Common mismatches

• Images of an older or foreign package version.
• A bundle or multipack listed on a single unit ASIN, or the reverse.
• Your own brand name, or no brand, on a listing for a branded product.

Amazon’s Intellectual Property policy describes a separate path for trademark or counterfeit concerns on the product detail page. Modify the detail page so it does not infringe the trademark and then appeal on the Account Health page, or appeal with supporting documentation if you believe the listing was removed in error. To prevent it, hold a unit next to the page before you join or create a listing.

Diagnosing a complaint that already arrived

Diagnosis has one goal, which is to find the birthplace before you write anything to Amazon. We ask every seller the same question before building a case. Are these goods genuine, and can you prove the sourcing with real documents that match the products and the volume? If the honest answer is yes, the case is mostly a documentation exercise. If it is no, no appeal language will change that, and the right move is to stop selling the item.

Where to verify each part

A worked example with hypothetical numbers

Take a reseller of a branded skincare serum that sold about 1,800 units through FBA from two suppliers over six months. In one month, four buyers complain. Two say the seal was broken, one says it “smells different,” and one says “fake.” An inauthentic violation appears on the Account Health page.

Instead of sending every invoice, the seller runs the trace. The invoices are genuine and cover all 1,800 units, so sourcing is documented. The returns report shows 26 returns of the SKU in the prior six weeks, 19 of them put back into sellable stock, and three of the four complaint orders shipped within days of those restocks. The “smells different” order shipped from an older inbound shipment whose units were close to expiration, a condition gap. The “fake” order came from the same returns window.

The root cause is not a counterfeit. It is a returns process that let opened units go back on sale for a product where an intact seal is how buyers judge authenticity, plus no rule on minimum remaining shelf life at receiving. The figures are hypothetical, but they show why the birthplace matters. An appeal that only said “our invoices prove the goods are genuine” would be true and would still not explain four complaints.

Turning the cause into a plan of action

Once you know the birthplace, the plan of action has three parts. For how reviewers read the whole document, see our guide to a plan of action that will not be ignored.

The root cause names a process

Reviewers reject vague causes such as “we made a mistake.” A useful root cause names the specific operational, sourcing, listing or documentation failure. For the example above, “Returned units of a sealed skincare product were restored to sellable inventory without our own inspection, and we had no minimum shelf life rule at receiving, so opened and short-dated units reached buyers.” Do not blame buyers, carriers, competitors or Amazon. Do not write that you sold counterfeit goods when the evidence shows otherwise.

Corrective actions are already done

List what you finished, with dates and numbers, such as listings paused, units removed with removal order IDs, units inspected, buyers refunded, invoices reconciled and a listing corrected.

Preventive measures have an owner and a date

Each control ties to the birthplace and names who owns it, when it started and how often it is checked. In the example, returned units of sealed products are set for removal and inspected by the seller before any resale, owned by the operations lead and checked weekly. Inbound units are checked against a written minimum shelf life rule at prep.

When genuine documents do not exist

If an invoice was never issued, you cannot create one now, and you must never alter a date, quantity, product name or business name on an existing document. Amazon’s policy allows only the removal of pricing. Ask the real supplier for genuine records. If the supplier will not or cannot provide them, say so honestly and treat the case as weak. A fabricated document turns a fixable complaint into a document integrity problem, as our guide to forged or manipulated documentation suspensions explains.

Related guides. Late Shipment Root Cause Analysis on Amazon and Amazon Product Safety Complaint Root Cause Analysis.

Preventing inauthentic complaints before they happen

Prevention is the same map read forward, with one control per birthplace.

Controls by birthplace

• Buyer wording. Review buyer messages, return comments and reviews for authenticity language on a fixed schedule, so you spot a theme at two complaints instead of ten.
• Condition and packaging. A receiving check that rejects opened, damaged, short-dated, sample or salvage units, and a prep rule that never covers seals or lot codes.
• Sourcing. Buy only from suppliers confirmed in a state registry, on invoices that name both businesses, the product and the quantity, and reconcile invoices to units each month.
• Test buys. Know who owns each brand you sell, keep any authorization on file, and check that your units match the brand’s current packaging for your market.
• Commingling. As a reseller, label every new FBA shipment with Amazon barcodes as Amazon now requires, and know which older stickerless stock is still selling.
• Returns. For products where condition signals authenticity, inspect returns yourself before resale, using the returns report and your removal settings.
• Listings. Compare a unit with the detail page before you list and again whenever the supplier, packaging or brand changes.

A weekly routine that takes under an hour

Each week, one named person checks the Account Health page, scans buyer messages and reviews for authenticity words, reviews the returns report and confirms new shipments were labeled. Each month, they reconcile invoices to units sold and spot check listings against units in hand. The written routine is itself a preventive measure you can show Amazon.

For a closely related case, read Amazon “Not as Described” Complaints.

Mistakes that turn a fixable complaint into a suspension

Amazon’s Account Health Rating policy explains why speed and accuracy both matter. The rating runs from 0 to 1,000 and reflects policy adherence over the last 180 days. Repeat violations of the same policy increase the points lost each time, and an account may be at immediate risk of deactivation if it reaches the maximum number of repeat violations for a single policy in a 180-day period, which can be as low as two for higher severity violations. A wrong root cause is how one complaint becomes a repeat.

The errors we see most are answering the messenger instead of the birthplace, invoices that do not match the listing’s product or quantity, blaming the buyer in the root cause, and relisting before the preventive control is running.

If you sell many brands and complaints are spreading, our rights owner complaint service and our Amazon suspension service handle both the brand side and the account side.

Frequently Asked Questions

What causes an inauthentic complaint on Amazon?

Usually one of seven things, namely the buyer’s experience of the unit, a condition or packaging gap, sourcing you cannot verify, a rights owner’s test buy, legacy commingled stock, a resold return, or a listing that does not match the product.

Can genuine products get an inauthentic complaint?

Yes. A genuine product that arrives opened, short-dated, in an unfamiliar package or unlike its listing can lead a buyer or brand to doubt it.

Does the end of commingling stop these complaints?

It removes one cause for new shipments. Resellers must use Amazon barcodes on shipments created after March 31, 2026, but older stickerless stock can still sell under its original SKU.

Can I edit an invoice before I send it to Amazon?

Only to remove pricing. Amazon’s Anti-Counterfeiting policy says any other edit, or a misleading document, is a violation.

How do I find out if a returned unit caused the complaint?

Use the FBA customer returns report and the LPN on returned items to compare return dates with complaint orders. For merchant fulfilled orders, use your own returns log.

How do I check that a supplier is real?

Look up the supplier’s legal name in its state business registry through nass.org and confirm it matches the invoice, address and status.

What if a brand test bought my product?

Inspect a unit from the same stock for variant, code or prep issues, and gather the invoices that trace your units to a legitimate source. A retraction request applies only where you have a real agreement with the rights owner.

Get Help With an Inauthentic Complaint

If you have an inauthentic violation on your Account Health page and are not sure where it was born, our team can trace it with you and build a plan of action around the real cause. You can submit your case for review or book a consultation to go through it.

This article is educational information, not legal advice. Amazon policies change. Confirm current requirements on the pages linked below and in your own Account Health notice before acting. No outcome, timeline or reinstatement is guaranteed.

Our rights owner complaint team can take the case from here. You can also see all our marketplace suspension services.

Sources

• Amazon Anti-Counterfeiting policy
• Amazon Intellectual Property Policy
• Amazon Condition guidelines
• Amazon FBA customer returns policy
• Amazon FBA Barcode Choice and Labeling FAQ
• Amazon: Use manufacturer barcodes for FBA
• Amazon FBA barcode requirements
• Amazon Account Health Rating program policy
• USPTO Trademark Search
• NASS: State business registration and corporate name databases