A counterfeit A. Lange & Sohne Saxonia 206.030 is easiest to catch at the movement, so that is the check to run first. Take the watch off its strap, turn it over, and look through the display back for a Lange-made calibre: Glashutte ribbing running across a three-quarter plate, a balance cock engraved by hand, screwed gold chatons, and heat-blued screws sitting flush with the plate. Reproductions tied to this reference number tend to hide a decorated third-party movement with stamped engraving, plated chatons, and screw slots that are already chewed. The criteria below are ordered by how hard each one is to copy: case and hallmarks, then dial and hands, then serials and paperwork. The harder the part is to fake, the more weight you should give it.

Movement finishing and architecture

The movement is the single most expensive thing to reproduce and the reason serious counterfeits of German watches fall apart under inspection. A genuine Saxonia movement shows hand-finishing that varies slightly from watch to watch, because a person did it. Fakes show finishing that is uniform to the millimeter, because a machine did it.

• Pro: it is decisive. A decorated third-party movement cannot be made to look like a hand-engraved Lange calibre, no matter how good the photos are.
• Pro: it needs no tools beyond a strap change, and you can compare what you see against reference photos of the real calibre.
• Con: it requires access to the watch. Sellers who refuse a display-back inspection, or who photograph only the dial, are telling you something.
• Con: you need to know the correct calibre for the exact reference before you look, since movements differ across the Saxonia line.

Use case: this is the check that matters for any private sale where the price is far below market and the seller has no service history to show.

Case, metal, and hallmarks

Look at the case back engraving first. On a genuine piece the reference number, case number, and metal stamp are crisp, deep, and consistent in depth. On counterfeits they are often shallow, uneven, or laser-etched with a dark fill that you can feel with a fingernail. Confirm the metal against the manufacturer's own reference data rather than the listing text, because a plated case can be described as solid gold by anyone with a keyboard.

• Pro: hallmarks and case back stamps are hard to fake at the right depth and font weight, and they are quick to inspect.
• Pro: weight and hand feel are useful supporting evidence when you have handled the real thing before.
• Con: case finishing is the area where counterfeits have improved most, so treat a clean case as neutral rather than as proof.
• Con: gold plating can look convincing in photos and even in the hand for a short time.

Use case: use this section as a filter when you are screening listings online, before you ever travel to see a watch.

Dial printing, hands, and proportions

Under a loupe, genuine dial printing has clean edges and no ink bleed. Counterfeit dials show fuzzy letter edges, flat applied markers with painted rather than polished bevels, and hands that are painted blue instead of heat-blued steel. Subdial spacing and hand lengths are also worth comparing against reference photos, because a fake dial is often slightly off in proportion rather than obviously wrong.

• Pro: a loupe and a set of reference photographs cost almost nothing and catch most bad fakes fast.
• Pro: fonts and marker geometry are difficult to duplicate exactly, and small errors compound.
• Con: dials are the cheapest component to copy and the easiest to photograph flatteringly, so dial alone never settles a purchase.

Use case: ideal for remote screening, where photos are all you have and you want to rule out obvious problems before spending money on an inspection.

Serials, papers, and provenance

Ask for the serial on the case back and the serial on the movement in the same photograph, and confirm they match. A genuine set usually includes the correct booklet and box, and often a service record from an authorized service center. Any seller who will not meet at a service center for a paid authentication is giving you your answer.

• Pro: provenance is the hardest thing for a counterfeiter to manufacture, since it depends on a paper trail the factory controls.
• Pro: a service center inspection is the closest thing to a definitive answer you can buy.
• Con: boxes and booklets are themselves counterfeited and sold separately, so papers alone prove very little.

Use case: mandatory for any transaction above a few thousand dollars, and worth the fee even when everything else looks right.

Before you pay: the practical recommendation

Rank your evidence in this order: movement, then case back and hallmarks, then provenance, then dial. If you are evaluating a watch that is being sold as a replica rather than as a genuine piece, understand what you are buying. Counterfeit trademarked goods are subject to seizure by U.S. Customs and Border Protection at import, and a replica movement cannot be serviced by the manufacturer or by most independent watchmakers, which means the first repair often costs more than the watch did. A watchmaker who refuses to work on it is not being difficult, they are being honest about parts availability. If your goal is a genuine Saxonia, buy from a seller who welcomes an inspection, pay through a method with recourse, and budget for authentication before you commit, not after.