Glossary
SIS (Schengen Information System)
The shared police database of the Schengen area. Includes alerts on stolen vehicles, missing documents, and persons wanted across the EU.
Definition
The Schengen Information System is the EU's largest police and border-control database, shared across all Schengen-area countries. It carries alerts on persons wanted for arrest, missing persons, persons subject to entry bans, stolen documents, and — relevantly here — stolen motor vehicles and stolen number plates. Frontline officers in every Schengen state can query SIS in real time, which is why a car stolen in Germany and driven into Poland is usually flagged at the first roadside check. The current SIS II (operational since 2013) holds tens of millions of vehicle and document alerts. Public access is not available; commercial stolen-vehicle checks that claim 'EU-wide' coverage typically combine national feeds that themselves are derived from SIS uploads.
Why it matters when buying a used car
SIS is the reason a stolen car driven across an EU internal border has a good chance of being detected by police. A theft check that includes SIS-derived data is materially stronger than one that does not.
Often confused with
Stolen vehicle check
Cross-referencing a VIN against national and international theft registers before purchase.
SMV
The international police database of stolen motor vehicles. Aggregates reports from 196 member countries.
VIN cloning
Stamping the VIN of a legitimate vehicle onto a stolen or written-off vehicle to give it a clean apparent identity.