Short answer
A. Lange & Söhne has not published a catalog entry for a 1815 with reference 268.026 that can be confirmed. The 1815 line uses references in the 233.xxx and 234.xxx ranges for the time-only and Up/Down models. A listing that pairs the number 268.026 with a price of a few hundred dollars is a counterfeit. A real 1815 sells new above $20,000 and holds value on the secondary market.
What the numbers mean
1815 is the model line. Lange named it for the birth year of Ferdinand Adolph Lange, who opened the Glashütte workshop in 1845. The company was expropriated in 1948 under the East German state. Walter Lange restarted the firm in 1990, and the first new collection appeared in 1994.
Lange reference numbers use six digits split by a dot. The last three digits encode case metal and dial variant. A number that looks plausible is easy to invent. The reference alone proves nothing.
Movement checks
This is the fastest test. Every Lange watch is mechanical. No Lange watch has used a quartz module, a battery, or a glued case back.
- Lange movements carry a three-quarter plate in untreated German silver, a copper-nickel-zinc alloy. Fake plates are brass with a nickel flash.
- The balance cock is hand-engraved by one engraver and signed with initials. Copies show laser etching with a flat, glossy surface.
- Screwed gold chatons hold the jewels. Fakes use gold-plated brass rings.
- Blued screws on a real Lange are heat-blued steel. Fakes are painted blue.
Open the case back. Many 1815 versions have a sapphire display back, so the movement sits in view.
Case, crystal and dial
- Measure the case. Lange publishes diameter and thickness for each reference. Copies run 1 mm to 2 mm off and sit thicker.
- Weigh the watch. Gold cases feel dense. A plated brass case at the same size weighs less and shows wear on the edges within months.
- Check the crystal. Lange uses sapphire with an anti-reflective coat on both faces. Copies use mineral glass that scratches and shows a purple or green tint at an angle.
- Read the dial print at 10x. Real print has crisp edges. Copies show fuzzy serifs and uneven spacing in the name.
- Check the hands. Blued steel hands are heat-blued and change tone with the light angle. Painted hands stay flat.
Papers, serials and price
Lange does not sell watches through an online store. Every sale goes through a boutique or an authorized dealer. A private listing with no box, no papers and no service history is a warning sign.
Serial numbers can be checked with A. Lange & Söhne customer service in Glashütte. Ask for the number stamped on the case back and the number engraved on the movement. Both should match and both should return the correct reference and metal.
Price is the last filter. A new 1815 in gold starts above $20,000. Used examples trade in the same range. Importing or selling counterfeits is illegal in the United States, and U.S. Customs can seize the shipment.
What is not known
I could not confirm that 268.026 is a valid Lange reference. Treat any listing that uses it as unverified until Lange confirms the number in writing.