What is the process for item authentication on resale platforms?

It varies a lot by platform. The RealReal and StockX physically inspect every item before it ships. Vestiaire Collective reviews photos at listing and adds a mandatory physical check for purchases over €1,000. eBay's Authenticity Guarantee and Poshmark's Posh Authenticate only cover specific categories, and on Poshmark only orders of $500 or more.

How reliable are authentication services for luxury goods?

Generally reliable, but not infallible. In March 2025, a federal court found that StockX had sold at least 37 counterfeit pairs of Nike sneakers despite marketing its process as a guarantee of authenticity. The RealReal's process was challenged in court by Chanel starting in 2018; a judge initially ruled the process sufficient, but the underlying case continued for years. Authentication catches the large majority of fakes. It hasn't caught all of them.

What happens if an item fails authentication?

On platforms with a mandatory check (The RealReal, StockX, Vestiaire above its threshold, Poshmark above $500), a failed item is pulled from the order, the sale is cancelled, and the buyer gets a full refund. Sellers with repeated failures can be flagged or restricted. On platforms without a physical check, there's no formal failure process, since nothing was inspected; a buyer who suspects a fake has to go through buyer protection or a payment dispute instead.

Why is authentication important in the resale market?

It's the main thing separating a resale marketplace from an unmoderated listings board. Buyers pay a premium to shop where items are checked because it removes the guesswork. The trade-off is that authentication only covers what each platform decides to cover, so it pays to know which categories and price points are actually being inspected versus taken on the seller's word.

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How Authentication Actually Works on Resale Sites (and Where It Fails)

Kevin GuiJune 18, 2026

Short answer: Resale platforms authenticate very differently from each other. Some physically inspect every item before it ships, some only check photos unless you're spending real money, and some only cover a narrow list of categories. None of them catch everything, which a 2025 court ruling against StockX confirmed in the most direct way possible.

In March 2025, a federal judge ruled that StockX had sold at least 37 counterfeit pairs of Nike sneakers, despite marketing its verification process as a guarantee of authenticity, in a lawsuit Nike filed in 2022. It's a useful reality check: "authenticated" on a resale platform means a specific company's specific process approved the item, not that fakes are mathematically impossible.

How the major platforms actually authenticate

Platform	How it works	When it applies	Known limitation
The RealReal	In-house authentication team manually inspects every item before it's listed for sale	Every item, every time	Challenged in court by Chanel starting in 2018; a 2019 ruling found the process sufficient, but the case continued for years afterward
Vestiaire Collective	Digital photo verification at listing; automatic physical authentication added for purchases over €1,000	Photo review always; physical check only above the threshold	Items priced below €1,000 rely on photo review alone, not a hands-on inspection
StockX	Item ships to a StockX verification facility and is physically inspected before being forwarded to the buyer	Every sale	A 2025 federal court ruling found StockX had sold at least 37 counterfeit Nike pairs despite its "100% Authentic" marketing
eBay (Authenticity Guarantee)	Third-party authentication partners physically inspect items in specific categories	Watches, sneakers, handbags, and select jewelry, within eligible price ranges	Items outside the covered categories or price ranges get no physical check at all
Poshmark (Posh Authenticate)	Poshmark's in-house team inspects logos, hardware, materials, and tags	Most categories, but only on orders of $500 or more	Below the $500 threshold, there's no authentication step; the buyer is relying on the seller's listing alone

What "failed authentication" actually means

When a platform runs a mandatory check and the item doesn't pass, the process is fairly consistent across the major players: the sale is cancelled, the buyer gets a full refund, and the item goes back to (or stays with) the seller, sometimes with their account flagged if it keeps happening. Poshmark states this directly for Posh Authenticate: if the team can't verify authenticity, the order is cancelled and refunded immediately.

What's less obvious is what happens on platforms, or at price points, where no physical check ever ran. There's no formal "failed" outcome there because nothing was inspected in the first place. If a buyer suspects a fake on an unauthenticated listing, their only path is the platform's general buyer protection policy or a payment dispute, not an authentication appeal, because no authentication happened.

The two real-world cases worth knowing

Nike v. StockX (filed 2022, settled 2025): Nike sued StockX over counterfeit sneakers and unauthorized NFTs tied to physical shoes. In March 2025, the court found that StockX had sold 37 counterfeit pairs, four bought by Nike's own investigators and 33 sold to a separate buyer. The companies settled on confidential terms that August. The case is the clearest documented instance of a major resale platform's "guaranteed authentic" claim not holding up in front of a judge.

Chanel v. The RealReal (filed 2018, still active in various forms): Chanel sued The RealReal alleging it knowingly sold counterfeit Chanel goods. A 2019 ruling found The RealReal's authentication procedures sufficient and dismissed that round of claims, but later rulings allowed some of Chanel's claims to proceed, and the case has continued through mediation years later. The takeaway isn't that The RealReal's process is bad; it's that even a platform with an in-house expert team built specifically for authentication hasn't fully settled the legal question of how good "good enough" needs to be.

What this means for how you shop

Don't treat "authenticated" as a single, uniform guarantee. Ask two questions before you trust it: did this specific platform physically inspect this specific item, and was the price high enough to trigger that inspection in the first place? A $300 Vestiaire listing and a $1,200 Vestiaire listing go through genuinely different processes. A $400 Poshmark handbag and a $600 one do too.

Knowing which platforms actually inspect what you're buying matters as much as the price tag. Crawli lets you compare the same item across The RealReal, Vestiaire, StockX, eBay, Poshmark, and more in one search, so you can weigh authentication coverage against price instead of guessing at either.