Resale platforms and independent services authenticate luxury goods before they change hands. The process examines manufacturing evidence rather than the features counterfeiters have learned to reproduce.
Construction is harder to fake than appearance
Surface details are copied readily, since a counterfeiter can photograph a genuine item and reproduce what is visible.
What is difficult to copy is how the item is assembled, because that requires the same equipment, materials and trained labor as the original.
Authenticators therefore concentrate on stitch density and angle, edge finishing, glue lines and the way linings are attached, which reflect factory process rather than design.
Hardware carries a great deal of information
Metal components are made to specific weights, finishes and tolerances, and the plating process leaves characteristics that are expensive to duplicate.
Engraving depth, font shape and the alignment of markings on hardware are assessed against known references for the period the item was made.
Weight is a practical early check, since the base metals used in counterfeits usually differ and the difference is detectable by hand.
Materials behave in ways that can be tested
Leather grain, smell and how a surface responds to pressure all reflect the tanning process, and substitutes behave differently under the same handling.
Fabric linings have identifiable weaves and weights, and printed patterns can be checked for alignment across seams, which requires deliberate cutting to achieve.
These assessments depend on tactile experience, which is why authentication remains difficult to perform reliably from photographs alone.
Codes and cards prove less than expected
Serial numbers, date codes and authenticity cards are among the first elements counterfeiters replicate, precisely because buyers are known to check them.
Their value to an authenticator is in consistency: a code that does not match the construction style or materials of its supposed period signals a problem.
An item with a plausible code and incorrect stitching fails, while an item with a damaged code and correct construction may pass.
The limits of the practice
Authentication is comparison against reference examples, so it depends on the authenticator having seen enough genuine items from the relevant period.
Older, rare and heavily restored items are hardest to assess, because reference material is thin and repairs alter the evidence being examined.
Serviced items complicate this further, since replacement parts fitted during repair are genuine but may not match the item's original specification.