How to Authenticate Designer Items: The Complete Reseller’s Guide to Spotting Fakes

Last month, a reseller on Reddit shared their nightmare: they bought what they thought was an authentic Gucci Dionysus bag from a local seller for $450, only to have eBay pull their listing and suspend their account 72 hours after they sold it. The reason? A buyer flagged it as counterfeit. The seller lost the bag, the sale, and their selling privileges—all because they couldn’t tell a $50 fake from a $1,500 authentic piece.

This story plays out hundreds of times every week across reselling communities. Counterfeit goods are more sophisticated than ever in 2026, and the consequences of accidentally selling a fake range from financial loss to legal liability to permanent platform bans.

Whether you’re flipping designer finds from thrift stores, sourcing from estate sales, or buying from online marketplaces, authentication is no longer optional—it’s a survival skill.

This guide covers everything you need to know about authenticating designer items: when to authenticate, how to do it yourself, when to pay for professional services, and brand-specific tells that separate real from fake.

In this guide, you’ll learn:

• Why authentication matters more than ever in 2026
• Three authentication methods (free to paid)
• Brand-specific guides for handbags, sneakers, watches, and clothing
• When to walk away from a deal
• How to protect yourself as a buyer and seller

Table of Contents

• Why Authentication Matters for Resellers
• The 3 Authentication Methods
• Designer Handbag Authentication
• Sneaker Authentication
• Luxury Watch Authentication
• Designer Clothing Authentication
• When to Walk Away
• Using Professional Authentication Services
• Protecting Yourself When Buying
• What to Do If You Accidentally Buy or Sell a Fake
• Frequently Asked Questions
• Related Tools

Why Authentication Matters for Resellers

The counterfeit market is a $500+ billion global industry, and it’s getting harder to spot fakes every year. In 2026, “superfakes” exist that require laboratory analysis or proprietary scanning technology to detect. Even experienced resellers get fooled.

Here’s what’s at stake when you sell an item that turns out to be counterfeit:

Platform Bans and Account Suspension

Every major reselling platform has strict policies against counterfeit goods:

• eBay: Immediate listing removal, potential permanent suspension, seller defect on account
• Poshmark: Account suspension, potential legal action
• Mercari: Permanent ban, no appeals for repeat offenders
• StockX/GOAT: Item rejected, shipping costs deducted, seller rating hit
• Facebook Marketplace: Account restrictions, removed from selling programs

One counterfeit sale can end a reselling business you’ve built over years. eBay’s VERO program (Verified Rights Owner) allows brands to report suspected counterfeits, and they don’t need proof—a single report can trigger removal and account review.

Legal Liability

Selling counterfeit goods is a federal crime in the United States. The Trademark Counterfeiting Act of 1984 makes trafficking in counterfeit goods punishable by:

• Up to 10 years in prison for first offense
• Fines up to $2 million for individuals
• Civil liability to trademark owners

While prosecutions typically target large-scale counterfeiters, individual resellers have been sued by brands. In 2024, Louis Vuitton won a $4.2 million judgment against resellers who “should have known” items were fake.

Ignorance is not a defense. When you list an item as “authentic,” you’re making a legal claim.

Financial Loss

Beyond legal issues, selling counterfeits costs you money:

• Lost inventory: Platform seizes or requires destruction of fake item
• Refunds: You refund the buyer but don’t get the item back (or get a fake returned)
• Shipping costs: Non-refundable shipping both ways
• PayPal/payment holds: Funds frozen during disputes (sometimes 180+ days)
• Reputation damage: Negative feedback, buyer reports, lost future sales

A single bad transaction can easily cost $500-2,000+ when you account for all expenses.

What Categories Need Authentication?

Not all designer items carry equal counterfeit risk. Here’s the risk hierarchy:

Highest Risk (Always Authenticate):

• Designer handbags (Louis Vuitton, Chanel, Gucci, Hermès, Dior)
• Limited edition sneakers (Off-White, Travis Scott, limited Jordans)
• Luxury watches (Rolex, Omega, Patek Philippe, Audemars Piguet)
• High-end streetwear (Supreme, BAPE, Fear of God)

Medium Risk (Authenticate If High Value):

• Designer sunglasses (Ray-Ban, Gucci, Prada)
• Designer wallets and small leather goods
• General release premium sneakers (regular Jordans, Yeezys)
• Designer clothing (Burberry, Moncler, Canada Goose)

Lower Risk (Visual Inspection Usually Sufficient):

• Premium athletic wear (Lululemon, Nike, Patagonia)
• Lower-tier designer (Coach, Michael Kors, Kate Spade)
• Vintage items (harder to fake, fewer fakes available)

The 3 Authentication Methods

You have three options for authenticating designer items, ranging from free (but skill-dependent) to paid (but reliable).

Method 1: Self-Authentication (Free, Requires Skill)

Best for: Lower-risk items, experienced resellers, quick sourcing decisions

Self-authentication means inspecting an item yourself using knowledge of authentic markers. This works for:

• Items under $200 where professional authentication isn’t cost-effective
• Brands you have extensive experience with
• Quick gut-check before paying for professional services

Pros:

• Free
• Instant
• No waiting period

Cons:

• Requires deep brand knowledge
• Mistakes are costly
• Won’t catch “superfakes”
• No documentation for disputes

How to learn: Study authentic items in stores, watch authentication YouTube videos, join reseller communities where experts share knowledge, and compare your items against verified authentic pieces.

Method 2: Professional Authentication Services ($10-50)

Best for: High-value items, brands with sophisticated fakes, buyer confidence

Professional authentication services employ trained experts (and sometimes AI/proprietary technology) to verify authenticity. The major services in 2026:

Entrupy ($10-30 per authentication)

• Uses AI and microscopic imaging
• 99.1% accuracy claimed
• Database of millions of authentic items
• Provides certificate with unique ID
• Best for: Handbags, small leather goods

Legit Check App ($5-20 per authentication)

• Human experts + AI assistance
• 24-48 hour turnaround
• Photo-based authentication
• Best for: Sneakers, streetwear, handbags

Real Authentication ($20-50 per authentication)

• Human experts only
• Physical inspection available (send item)
• Detailed reports
• Best for: Watches, jewelry, high-value items

CheckCheck ($3-15 per authentication)

• Photo-based, AI-assisted
• Fast turnaround (under 24 hours)
• Best for: Sneakers

Pros:

• Expert opinion
• Documentation for disputes
• Catches sophisticated fakes
• Builds buyer confidence

Cons:

• Cost per item adds up
• Waiting period (hours to days)
• Photo quality affects accuracy
• Rare items may lack comparison data

When to use: Any item over $300-500 resale value, any category with sophisticated fakes, or whenever you have doubts.

Method 3: Platform Built-In Authentication (Free for Sellers)

Best for: Eligible categories on supported platforms

Several platforms now offer authentication services included in their selling process:

eBay Authenticity Guarantee

eBay’s free authentication service for:

• Watches over $2,000
• Sneakers over $100 (Nike, Adidas, Jordan, Yeezy, New Balance)
• Handbags over $500 (select brands)
• Trading cards over $750

How it works:

1. You list eligible item
2. Buyer purchases
3. Item ships to eBay authenticator (not direct to buyer)
4. Expert authenticates (2-4 business days)
5. If authentic, eBay adds authenticity tag and ships to buyer
6. If fake, item returned to seller, transaction canceled

Pros: Free for sellers, builds buyer trust, reduces return fraud Cons: Only specific categories/price points, adds shipping time, potential for authenticator error

StockX and GOAT Authentication

Both platforms authenticate every item:

1. Seller ships to StockX/GOAT
2. Item authenticated by experts
3. If authentic, ships to buyer
4. If fake, seller penalized (fee deduction, account strike)

Pros: Every item authenticated, high buyer confidence, premium prices Cons: Heavy fees (8-12%), strict condition requirements, potential false rejections

Poshmark Authentication (Posh Protect)

Poshmark’s authentication program:

• Covers luxury items over $500
• Buyer requests authentication
• Poshmark sends shipping label to buyer
• Item authenticated, then shipped to buyer

Designer Handbag Authentication

Handbags are the most counterfeited designer category and the highest-risk for resellers. Here are brand-specific authentication guides:

Louis Vuitton

Louis Vuitton is the most counterfeited brand in the world. Key authentication points:

The Date Code

• Pre-2021: Look for date code stamped inside bag (two letters + four numbers)
• Letters indicate factory location (e.g., SD = USA, FL = France)
• Numbers indicate manufacturing date
• Post-2021: Microchip replaced date codes (requires Louis Vuitton to verify)

Date code format:

• Pre-2007: Two letters + three/four numbers (e.g., FL0012 = January 2002)
• 2007-2021: Two letters + four numbers alternating (e.g., SD1029 = 12th week of 2009)

Pro tip: Many fakes have date codes in wrong locations or impossible date combinations. Research where the date code should be for each specific model.

Canvas Quality (Monogram/Damier)

• Pattern should be symmetrical on front
• Pattern can be cut off asymmetrically on back/sides (normal)
• Canvas should feel dry/textured, not plasticky
• Color should be consistent, not yellowish or orange-tinged

Stitching

• Yellow/mustard color thread
• Even, consistent stitching (hand-stitched pieces may have slight variation)
• No loose threads
• Stitches should go into the leather at consistent angles

Hardware

• Engravings should be clean, crisp, evenly spaced
• “LOUIS VUITTON PARIS” stamped on all hardware
• Hardware should have weight/substance
• Zippers should operate smoothly (typically YKK or Lampo)

Red Flags:

• Plastic-feeling canvas (should feel textured/dry)
• Uneven or crooked stitching
• “Made in China” stamping (LV only makes in France, Spain, USA, rarely Italy)
• Serial numbers (LV uses date codes, not serial numbers)
• Attached authenticity cards (LV doesn’t include these)
• Cheap, lightweight zipper pulls

Gucci

Serial Number Tag

• Located inside bag on leather tag
• Two rows of numbers (top row = style code, bottom row = supplier code)
• Modern bags: 10-13 digits total
• Font should be clean, evenly spaced

The GG Canvas

• G’s should interlock perfectly
• Pattern should be symmetrical
• Canvas should feel substantial, slightly textured
• Color should be consistent

Leather Quality

• Gucci uses high-quality treated leather
• Should feel soft but substantial
• Edges should be cleanly finished

Controllato Tag

• White fabric tag inside bag
• Says “GUCCI” with “Controllato” card number
• Font should be specific Gucci typeface

Red Flags:

• Serial number font that’s too thick or thin
• Cheap-feeling canvas or leather
• Misspellings on interior tags
• Hardware without Gucci engravings
• Dustbag quality (authentic dustbags are high-quality flannel)

Chanel

Authenticity Card and Sticker

• Authenticity card has gold serial number
• Matching sticker inside bag (usually in interior pocket)
• Numbers must match exactly
• Serial number format varies by era (research specific year)

The CC Turn Lock

• Right C overlaps left C at top
• Left C overlaps right C at bottom
• Engraving should be crisp and centered
• Hardware should feel substantial

Quilting

• Diamond pattern should align across seams
• Stitches should follow quilting pattern
• Puffiness should be consistent

Chain Strap

• Leather woven through chain
• Chain links should be fully closed (no gaps)
• Hardware should match throughout bag

Red Flags:

• CC lock where both C’s overlap same direction
• Quilting that doesn’t align at seams
• Authenticity card without matching sticker
• Light, hollow-feeling hardware
• Crooked stitching on quilting

Coach

Coach is lower-tier luxury but still counterfeited. Key checks:

Serial Number/Creed Patch

• Leather patch inside bag with serial number
• Format: Letters + numbers indicating style and production
• Creed should mention “Coach” and manufacturing country

Stitching

• Even, consistent stitches
• Thread color should match leather
• No loose threads or skipped stitches

Hardware

• Should say “Coach” on zippers/pulls
• Metal should have substantial weight
• Turnlocks engraved “Coach”

Coach Fabric/Signature

• “Coach” in repeating pattern
• Should be aligned and consistent
• Colors should be true to authentic (compare online)

Red Flags:

• Creed patch without serial number
• “Coach” misspelled on fabric
• Light, cheap-feeling hardware
• Stitching in wrong color thread

Sneaker Authentication

The sneaker resale market is massive, and counterfeits range from obvious to nearly undetectable. Here’s how to authenticate the most commonly faked silhouettes:

Jordan Authenticity Guide

The Box

• Box label matches shoe (size, colorway, style code)
• Label barcode should scan correctly
• Box quality should be substantial cardboard
• Box size should match shoe size appropriately

Style Code Verification

• Located on box label and tongue tag
• Format: Letters-Numbers (e.g., DH3434-001)
• Should match Nike database (use Nike Style Code Lookup)
• Colorway should match the style code exactly

Stitching Quality

• Clean, even stitching throughout
• Thread color should match design
• No fraying or loose threads
• Wings logo on Jordan 1s should have clean stitching

Nike Air/Jumpman Logo

• Jumpman proportions should be correct
• Nike Air text should be crisp
• Logos should be level/straight
• Embossed logos should have clean edges

Material Quality

• Leather should feel substantial (varies by model)
• Suede should have proper nap/texture
• Colors should match authentic releases (compare to retail photos)

Red Flags:

• Style code doesn’t exist or matches different shoe
• Box label quality issues (fuzzy printing, wrong font)
• Jumpman logo with wrong proportions
• Glue stains or excess glue visible
• Incorrect tongue tag (wrong font, spacing, country)
• Shoe trees included (Nike doesn’t include these)
• Strong chemical smell (factories smell different)

Yeezy Authenticity Guide

Boost Technology

• Real Boost has distinctive oval pellet pattern
• Pellets should be consistent size
• Boost should be squishy/responsive
• Fake Boost often looks like styrofoam

Pull Tab Position

• Position varies by model/colorway (research specific release)
• Should be centered and even
• Stitching should be clean
• Some Yeezy 350 V2s don’t have pull tabs (verify for colorway)

Heel Bump

• Should have visible heel bump
• Shape should match authentic (varies by batch/era)
• Proportions should match authenticated examples

Primeknit Quality

• Knit pattern should be consistent
• Colors should match authentic releases
• Pattern should be symmetrical

Box Label

• Should include EU, UK, US, and CM sizing
• Style code should match shoe
• Manufacturing country (usually China, Vietnam, India)

Red Flags:

• Boost that looks like styrofoam rather than distinct pellets
• Pull tab in wrong position for colorway
• Strong chemical smell
• Primeknit pattern that doesn’t match retail
• Wrong box size (box should match shoe size)

Nike Dunk Authentication

Swoosh Quality

• Should be smooth leather/suede
• Shape should be consistent on both shoes
• Stitching around swoosh should be even
• Position should match authentic pairs

Toe Box Shape

• Shape varies by era/release
• Should match authenticated examples
• Stitching should be clean

Insole

• Nike branding should be centered
• Font should be correct
• Insole should fit properly (not loose/shifting)

Tongue Tag

• “NIKE” and swoosh logo
• Country of manufacture
• Style code and size information
• Font should be correct (compare to authentic)

Red Flags:

• Swoosh shape/position doesn’t match retail
• Tongue tag with wrong font or spacing
• Excess glue throughout
• Toe box shape significantly different from authentic
• Heel embroidery with wrong font/position

Luxury Watch Authentication

Watch counterfeiting is sophisticated and high-stakes. Professional authentication is strongly recommended for any watch over $1,000.

Rolex Authentication

Movement

• Heart of Rolex authentication
• Should sweep smoothly (not tick)
• Rotor should be engraved “ROLEX” with crown logo
• Requires case back removal (professional tools needed)

Crown Logo

• Crown logo on dial should be perfectly formed
• “ROLEX” text should be crisp
• Coronet (crown) on bezel aligned properly

Cyclops Lens

• Magnifies date 2.5x
• Should be centered over date window
• High-quality magnification (fakes often 1.5x)

Serial and Model Numbers

• Serial number between lugs at 6 o’clock (vintage) or on rehaut (modern)
• Model number between lugs at 12 o’clock
• Font should be finely engraved

Weight

• Real Rolex has substantial weight (solid metal)
• Fakes often feel light
• Weight varies by model (research specific reference)

Water Resistance

• Screw-down crown should be secure
• Gaskets should be visible (professional inspection)
• Real Rolex waterproof to rated depth

Red Flags:

• Ticking second hand (should sweep)
• Cyclops with low magnification
• Misspellings on dial
• Light weight for model
• Crown logo imperfections
• Clear case back (Rolex doesn’t make display backs)
• Papers without matching serial number

Pro tip: Always get Rolex professionally authenticated. Superfakes exist that require movement inspection to detect.

Omega Authentication

Co-Axial Movement

• Omega’s proprietary movement technology
• Requires professional inspection
• Decoratively finished (visible through display backs on many models)

Serial Number

• Engraved on case between lugs
• 8 digits (modern references)
• Should match card/paperwork

NAIAD Lock Case Back (Modern Models)

• Omega logo and text always aligned
• Clean, precise engraving
• Text runs along case back edge

Dial Details

• Applied logos should have clean edges
• Printing should be crisp
• Colors should match authentic (research specific reference)

Red Flags:

• Movement doesn’t match model (requires professional inspection)
• Serial number doesn’t verify with Omega
• Poor dial printing quality
• Applied logos with rough edges
• Improper lume (should glow green/blue, not yellow)

When to Use Professional Watch Authentication

Always pay for professional authentication when:

• Watch value is over $1,000
• You’re buying from an individual (not authorized dealer)
• Papers/box are missing
• Price seems too good
• Any authentication markers seem questionable

Recommended watch authentication services:

• Chrono24 (platform authentication)
• Watchfinder (in-house authentication)
• Local authorized service centers
• Third-party specialists (research reputation)

Designer Clothing Authentication

Supreme

Supreme counterfeits range from obvious to very sophisticated. Key authentication points:

Box Logo (Bogo) Authentication

• Stitching should cross at intersection points
• Letters should have small thread gaps
• Logo placement should be centered
• Stitching should be clean, not loose

Tag Authentication

• “Supreme” tag should have correct font
• Made in Canada/USA tags (depending on era/item)
• QC code on modern items
• “100% cotton” text should be proper font

Print Quality

• Screen prints should be crisp, not fuzzy
• Colors should be saturated, not faded
• No cracking on print (unless vintage/worn)

Red Flags:

• Box logo where threads don’t touch
• “Made in China” on items that should be USA/Canada
• Wrong fonts on tags
• Loose, sloppy stitching
• Colors that don’t match known authentic pieces

BAPE (A Bathing Ape)

Camo Pattern

• Authentic BAPE camo has specific ape head shapes
• Colors should be consistent with authentic releases
• Pattern should match known patterns for specific piece

WGM (World Gone Mad) Shark Hoodie

• Teeth should be aligned across zipper
• Eye placement should be symmetrical
• Stitching should be clean

Tags

• BAPE tags have specific fonts and formatting
• Should include care instructions
• Made in Japan or China (depending on line/era)

Golden Zippers

• Authentic BAPE uses YKK zippers
• Should say “BAPE” on zipper pull
• Heavy, quality construction

Red Flags:

• Teeth that don’t align when zipped
• Wrong ape shapes in camo pattern
• Cheap, light zippers
• Incorrect tag fonts

Moncler

Comic Strip Logo Patch

• Multiple colors, crisp printing
• Cartoon character should be detailed
• Colors should be vibrant
• Stitching around patch should be clean

Certilogo (QR Code)

• Scannable code inside jacket
• Verifies authenticity through Moncler database
• Each jacket has unique code
• Required check for any modern Moncler

Down Quality

• Should be fluffy, premium down
• Should recover shape after compression
• Weight should be substantial for warmth
• No feathers poking through

Red Flags:

• Certilogo that doesn’t verify (instant fake indicator)
• Low-quality down that doesn’t recover
• Blurry or off-color comic logo
• Labels with misspellings or wrong fonts

When to Walk Away

Some deals aren’t worth the authentication risk. Walk away when:

Red Flags in the Seller

• Refuses additional photos: Legitimate sellers are happy to provide more images
• Vague about authenticity: “I think it’s real” or “it looks authentic” isn’t enough
• Story doesn’t add up: Claims they bought it but has no receipt/proof
• Price is too good: Authentic Hermès Birkin for $800 is a scam
• Multiple luxury items at low prices: Likely a counterfeit operation
• High pressure to buy now: Scammers don’t want you to think or research

Red Flags in the Item

• Can’t verify any authentication markers: Date codes, serial numbers, style codes
• Multiple quality issues: One flaw might be manufacturing variance; multiple flaws = fake
• Missing documentation when it should exist: Modern luxury pieces include cards/receipts
• Authentication markers don’t match: Date code style wrong for claimed year
• Too perfect: Sometimes fakes look “too new” compared to claimed age

Categories with Extreme Fake Risk

These categories have such sophisticated fakes that you should only buy from:

• Authorized retailers
• Platform-authenticated sources
• Sellers with extensive proof of purchase

Highest fake saturation (proceed with extreme caution):

• Hermès Birkin/Kelly bags
• Limited edition Off-White Nike collaborations
• Rolex sports models (Submariner, Daytona)
• Vintage Chanel quilted bags
• Supreme box logo items
• Travis Scott Nike collaborations

Using Professional Authentication Services

When to pay for professional authentication and how to use each service:

When to Pay for Authentication

Always authenticate when:

• Item resale value exceeds $300
• You have any doubts about authenticity
• Brand is commonly counterfeited
• Buyer requests authentication
• You’re selling on eBay/Poshmark at premium prices

Cost-benefit calculation:

• $20 authentication on a $500 bag = 4% of sale value = worth it
• $20 authentication on a $50 Coach wallet = 40% of value = probably skip

Using Entrupy

Best for: Handbags, small leather goods

Process:

1. Download Entrupy app and create account
2. Select brand and item type
3. Take required photos (specific angles/details)
4. Submit for analysis
5. Receive results in 2-24 hours
6. Get certificate PDF for proven authentic items

Tips:

• Use good lighting (natural light best)
• Follow photo instructions exactly
• Include date code/serial number photos
• Submit clear, focused images

Using eBay Authenticity Guarantee

Best for: Sneakers, watches, trading cards (if selling on eBay)

Process:

1. List eligible item on eBay
2. Automatically enrolled if item meets criteria
3. Buyer purchases
4. Ship to eBay authenticator (free label provided)
5. eBay authenticates and ships to buyer
6. Authenticity tag attached to item

Tips:

• Include original packaging when possible
• Pack carefully (items rejected if damaged in transit)
• Be accurate about condition (strict standards)
• Allow extra processing time (tell buyers)

Using Legit Check App

Best for: Sneakers, streetwear

Process:

1. Download Legit Check app
2. Select item category and brand
3. Upload required photos
4. Include original box photos if available
5. Receive expert verdict (usually 24-48 hours)
6. Get shareable certificate for authentic items

Protecting Yourself When Buying

In-Person Buying Protocol

When buying designer items locally:

1. Request photos before meeting (detailed shots of all authentication markers)
2. Research the item (know what authentic looks like before you go)
3. Bring a reference device (phone with comparison images)
4. Meet in public, well-lit location
5. Inspect thoroughly before paying (use authentication checklist)
6. Request receipt/proof of purchase (ask before meeting)
7. Use payment method with protection (PayPal G&S, credit card)
8. Trust your gut (if something feels wrong, walk away)

Online Buying Protocol

When buying designer items online:

1. Request additional photos (specific authentication markers)
2. Ask for proof of purchase (receipts, authentication certificates)
3. Research seller history (ratings, past sales, account age)
4. Use platform protection (never pay outside platform)
5. Verify serial/date codes (match format for brand/era)
6. Compare to authenticated examples (not just stock photos)
7. Consider professional authentication (for high-value items)
8. Know platform return policies (eBay MBG, PayPal protection)

Platform Protection Comparison

What to Do If You Accidentally Buy or Sell a Fake

If You Bought a Fake

Step 1: Document everything

• Take detailed photos of all authentication issues
• Screenshot your original purchase and communications
• Save any authentication reports (failed Entrupy, etc.)

Step 2: Contact seller immediately

• Request refund with documentation
• Be professional but firm
• Give reasonable deadline (48-72 hours)

Step 3: Open platform dispute

• File “Item Not As Described” or “Counterfeit” claim
• Upload all documentation
• Respond promptly to platform requests

Step 4: Escalate if needed

• PayPal buyer protection (if purchase used PayPal)
• Credit card chargeback (if seller won’t refund)
• Small claims court (for high-value items)

Step 5: Report the seller

• Report listing to platform
• Report seller account
• Leave appropriate feedback (if platform allows)

If You Accidentally Sold a Fake

Step 1: Accept responsibility

• Don’t argue with buyer
• Offer immediate full refund
• Apologize for the error

Step 2: Refund immediately

• Full refund including shipping
• Don’t wait for item return (shows good faith)
• Consider eating the loss to save your account

Step 3: Remove similar items

• Pull any related listings
• Re-examine your inventory
• Consider professional authentication for remaining items

Step 4: Document for future

• Note where you sourced the item (avoid that source)
• Update your authentication process
• Consider carrying authentication insurance (exists for dealers)

Step 5: Communicate with platform

• If reported, respond honestly
• Explain it was unintentional
• Show your corrective actions
• First offense usually gets warning, not ban

Frequently Asked Questions

How accurate are professional authentication services?

The major services claim 98-99%+ accuracy. Entrupy specifically claims 99.1% accuracy for handbags using AI analysis. However, even the best services make occasional errors. For extremely high-value items ($10,000+), consider multiple authentication services.

Can I authenticate items using just photos?

Yes, but with limitations. Photo-based authentication can identify obvious fakes and many sophisticated ones, but cannot verify materials, weight, or movement (watches). For items over $500, physical inspection or professional service is recommended.

Are authentication services liable if they get it wrong?

Most services have liability limitations in their terms of service. Entrupy, for example, offers a limited warranty. If an authenticated item is later proven fake, they may offer refund of authentication fee but typically not item value. Read terms carefully.

How do I authenticate vintage items?

Vintage authentication requires era-specific knowledge. Date codes, materials, manufacturing techniques, and style details all vary by era. Resources like Vintage Fashion Guild and era-specific guides are helpful. When in doubt, seek authentication from experts who specialize in the specific brand and era.

Is it worth authenticating items under $100?

Generally no. $15-30 authentication on a $100 item is 15-30% of your potential profit. For lower-value items, develop self-authentication skills and accept the rare loss as cost of business. Exception: if you’re building reputation and buyer requests authentication.

What’s the difference between “replica,” “inspired by,” and “counterfeit”?

• Counterfeit: Fake item sold as authentic (illegal)
• Replica: Acknowledged copy, doesn’t claim authenticity (may violate trademark)
• Inspired by: Original design influenced by brand (legal if no trademarks used)

All three can get you in trouble if you sell them as authentic. “Inspired by” items with brand logos are still trademark violations.

How can I tell if authentication papers/receipts are fake?

Authentication papers and receipts are also counterfeited. Red flags include:

• Paper quality doesn’t match brand standards
• Fonts incorrect for brand
• Serial numbers don’t match item
• Dates don’t make sense (receipt dated before item released)
• No seller address or includes generic address

When in doubt, contact the brand directly to verify.

Should I buy from sellers who say “I think it’s authentic”?

This is a red flag. Legitimate sellers know if their items are authentic. “I think” means:

• They bought from questionable source
• They can’t authenticate themselves
• They’re hedging against return claims

If seller can’t confirm authenticity, price should reflect risk or you should walk away.

Do thrift stores ever have authentic designer items?

Yes, but carefully. Goodwill and other thrift stores don’t authenticate donations. Authentic pieces do end up in thrift stores from estate donations, closet cleanouts, and gifted items. However, fakes donated by people who got scammed also end up there. Apply the same authentication standards you would anywhere.

What percentage of designer items online are fake?

Estimates vary significantly by category:

• General marketplaces (Facebook, Craigslist): 20-40% designer items may be fake
• eBay (non-authenticated): 5-15% designer items may be counterfeit
• StockX/GOAT (authenticated): Under 1% fake catch rate
• Consignment (e.g., The RealReal): Under 2% fake (they authenticate)

These are industry estimates; actual rates vary by brand and price point.

Can customs seize items if they suspect they’re counterfeit?

Yes. U.S. Customs and Border Protection (CBP) has authority to seize counterfeit goods. If you import items that CBP suspects are fake, they can:

• Seize the item
• Destroy the item
• Refer for criminal investigation
• Fine the importer

This primarily affects bulk importers, but individual shipments can be seized if obviously counterfeit.

How do I build authentication skills faster?

Best ways to learn:

1. Handle authentic items: Visit designer boutiques, touch materials, study details
2. Study authenticated examples: Watch authentication videos on YouTube
3. Join reseller communities: r/fashionreps (to learn fake tells), reseller Discord servers
4. Use authentication services: Learn from what they flag
5. Compare side-by-side: Photos of authentic vs fake (many available online)
6. Focus on 1-2 brands: Deep knowledge beats broad familiarity

Related Tools

Building authentication skills takes time, but the right tools speed up the process:

• Nike Style Code Lookup - Verify Nike/Jordan style codes against database
• Brand Resale Value Index - Check brand authenticity risk and resale value
• ROI Calculator for Resellers - Factor authentication costs into profit
• eBay Sold Link Generator - Research authentic sold prices

Conclusion: When in Doubt, Get It Authenticated

The counterfeit market isn’t going away. In 2026, fakes are more sophisticated than ever, and the consequences of accidentally selling counterfeits are severe: financial loss, platform bans, legal liability, and reputation damage.

But here’s the good news: with the right knowledge and systems, you can protect yourself and your business. The key is understanding when to self-authenticate, when to pay for professional services, and when to walk away entirely.

The golden rule of authentication: If you can’t confidently verify authenticity, don’t buy it. If you bought it but have doubts, authenticate before selling. If authentication fails, eat the loss—it’s cheaper than the alternatives.

Build your authentication skills over time by handling authentic items, studying brand-specific tells, and learning from authentication services. Specialize in 2-3 brands you understand deeply rather than trying to authenticate everything.

And remember: the $20-30 you spend on professional authentication is the cheapest insurance policy in reselling. One prevented platform ban or legal issue pays for hundreds of authentication fees.

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Related Guides:

• Thrift Store Flipping: The Complete Guide
• Best Things to Flip for Profit in 2026
• What Is This Worth? Complete Guide
• Why Most Resellers Lose Money