Hermès is the highest-stakes check in the resale market, the Birkin and Kelly most of all, because the prices are large and the fakes have gotten good. Hermès uses no serial number and no online date lookup, so the bag has to tell its own story through the stamp and the stitching.
The blind stamp, and what it dates
A small heat stamp, a letter inside a shape, sits hidden under the front flap, pressed without ink and deliberately hard to find. The shape around the letter places the era: no shape before 1971, a circle from 1971 to 1996, a square from 1997 to 2014, and no shape again from late 2014. It dates the bag and corroborates the rest, but it does not authenticate on its own, because the formats are known and copied.
The craftsman's mark
One artisan builds and repairs an entire Hermès bag, and leaves a small separate maker's mark near the blind stamp. Fakes often skip it entirely, so its absence is a real warning sign.
The stitching
The hallmark is the saddle stitch, sewn by hand with two needles passing through each hole. It leaves a slightly raised, even line that leans gently on the diagonal, in waxed linen thread. Perfectly straight, machine-uniform stitching is the opposite of what a hand-finished Hermès looks like.
Hardware, zip, and lock
The HERMÈS PARIS engraving is crisp and evenly spaced, and the plating should not wear away to a different color underneath. A real zip pull rests parallel to the zip rather than flopping to a right angle, and the padlock is cleanly engraved with a number that matches both keys.
When to call in a pro
With this much money on the line, the markers are where you start, not where you stop. A strong fake clears a visual check, the leathers and stamps shift across decades, and the difference can come down to a millimeter of stitch lean. For any Birkin or Kelly purchase, and before you sell or insure, have a professional authenticator handle it in person.
Sources
Drawn from authentication services and reseller guides, including Retyche, and cross-checked against our own Hermès archive, in June 2026. The exotic blind-stamp symbols and leather dates are useful context, but we present them as markers to weigh, not as a verdict.
