Short answer
The fastest tell is the case. A genuine Speedmaster Dark Side of the Moon (ref. 311.92.44.51.01.003 and its siblings) is made from black zirconium oxide ceramic, and fakes almost always cheat here with a steel case finished in black PVD or DLC. Check the bezel next. The tachymeter scale on the real watch is Liquidmetal, a metallic glass fused into the ceramic so the numerals sit flush with the surface. On a fake, that scale is printed, painted, or engraved and filled, so you can see and feel an edge. Then let the movement decide. Ask for photos through the display back and compare finishing, engraving, and the layout of the chronograph works.
Case and bezel: where copies fall apart first
Ceramic versus coated steel
Real ceramic does not chip like paint and it does not scuff like metal. It stays cool to the touch, has a deep, hard gloss on the polished surfaces, and holds a crisp line where polished meets brushed. Coated steel fakes look close in photos and obvious in hand: the coating feels slightly soft, edges look rounded or over-polished, and a light fingernail test on a hidden spot can leave a mark. Weight helps too. A 44.25 mm ceramic case should not feel like a steel brick of the same bulk, so if it feels heavy for its size, look closer.
Liquidmetal tachymeter
Run a fingertip around the bezel. The genuine scale is level with the ceramic, no ridges, no gloss difference, no paint sitting on top. Most fakes show a raised or recessed scale, uneven dots and numerals, or a glossy fill that catches light differently from the bezel around it. The dot over 90 and the spacing at 400 and 500 are common giveaways.
Dial, subdials, and hands
The layout should match the 9300 or 9900 calibre family: a combined 60-minute and 12-hour counter at 3 o'clock, small seconds at 9 o'clock, and a date window at 6. Fakes often use a generic chronograph movement that forces the subdials into a different position or a different spacing.
- Subdial rings should be recessed with fine circular snailing and a matte, even texture.
- Applied hour markers sit flat and clean, with lume that fills the frame evenly.
- Hands should line up dead center on the subdials when the chronograph is reset.
- Print is sharp under a loupe. Blurry or thick text is a warning sign.
- The date sits centered in the window with even gaps on both sides.
The movement is the real dividing line
Omega's 9300 and the later 9900 are twin-barrel, column-wheel chronographs with a co-axial escapement and a silicon balance spring. Through the sapphire caseback you should see dark, well-finished bridges, a decorated rotor, and clean engraving. Fakes usually run a Seagull ST19 or a modified 7750 under a printed or plated cover plate. Look for lazy finishing, wrong rotor text, screws that look stamped rather than turned, and a balance wheel ticking at a rate that does not match a smooth sweep. The newer version also carries Master Chronometer certification, which is a measurable standard, not a slogan.
Caseback, crown, and engraving
Engraving on genuine ceramic is cut clean and deep, including the model name around the caseback and the markings on the crown. Fakes tend to show shallow laser etching with soft edges or a font that is a hair too wide. Serial numbers on the case and movement should be consistent with the paperwork, and the numbers on a Master Chronometer card should be unique to that watch. If the seller cannot show matching numbers, stop there.
Strap, clasp, box, and papers
The stock strap is a tightly woven black fabric with coated hardware, and the stitching runs straight and dense. Replacements are easy to source, so a worn strap proves nothing either way, but cheap hardware does. Boxes are the weakest link in any fake package. The genuine box is heavy, correctly printed, and comes with a card, a manual, and a pictogram or certificate that matches the reference.
Price and provenance
Retail on this model is well over five figures in US dollars, and even used examples hold strong value. Fakes sell for a few hundred dollars, and the better copies creep into four figures. Any listing far below the market is not a bargain, and any seller who pushes you to move fast, take it off-platform, or skip an inspection is telling you what you need to know.
Pre-purchase checklist
- Photograph the bezel scale at an angle in daylight.
- Ask for clear movement shots through the caseback.
- Compare reference number, serial, and card.
- Weigh and feel the case against a known ceramic watch.
- Have an independent watchmaker open it before money changes hands.
Do those five things and the answer is usually obvious in about a minute. Ceramic and Liquidmetal are expensive to copy well, and the movement is nearly impossible to fake on a budget, so the watch tends to confess on its own.