Jan 09, 2018 Omega assigns a serial number to each of its pieces as a mark of authenticity. Should your Omega have a serial number, it's usually worth searching it on the internet, as replicas tend to use the same numbers for multiple versions of the same watch. These copycat serials are often flagged up among the watch community as typical fakes. The following 'Round Numbers' Serial Number List has been comprised of known serial number ranges for the years listed. By checking a particular serial number against this list you should be able to date a watch with reasonable accuracy. However, it is no quarantee as to when your watch was shipped from the factory.