Look for the laser-etched coronet in the sapphire crystal. Located near the 6 o'clock position, this marking is very difficult to see with the naked eye. If the original crystal has been replaced, there will be an "S" etched beside the coronet. This security feature was added gradually and therefore, earlier models (pre-2004) may not have this marking. Counterfeit watches can possess a coronet marking; however, the marking can be seen without aid of a magnifying glass. The presence of the coronet marking alone does not guarantee authenticity.
Look for the green hologram sticker on brand new Rolex watches. This specially-designed sticker contains the word "ROLEX," the Rolex Coronet and a reference number printed in black, directly below the coronet. When worn, the reference number will wear off very quickly. Some prefer to remove the hologram sticker and keep it with the original packaging for later authenticity verification.
Observe the watch case back. There are no current models in existence to sport a transparent case back. Only some very rare 1930 models and the Cellini Prince model have been manufactured with a transparent back.
Note that Rolex watches typically do not have a any engravings on the outside of the case back. The only exceptions being certain lady's Rolex watches, the Sea-Dweller watch, which contains the wording "Rolex Oyster Original Gas Escape Valve" and two Rolex logos, as well as some early TUDOR models, some of which contain the wording "Original Oyster Case by Rolex."
Ascertain that the watch covering is the true Rolex sapphire crystal. Counterfeit watches will often use regular glass.
Observe the case reference numbers. Reference numbers are engraved with great precision and are very smooth on an authentic Rolex watch. A counterfeit watch will possess case reference numbers which are roughly etched into the case.
Consult an authorized Rolex dealer to confirm the authenticity of a Rolex watch. This is the only true way to confirm that your Rolex is real.