The Metropolitan Police Cabs Unit team conducted roadside spot checks on taxi and private hire vehicles and drivers in London throughout Thursday 23 July.
Among those stopped was a non-private hire driver licence holder, driving what appeared to be a Transport for London licensed minicab.
Closer inspection showed that the vehicle's licence roundels were in fact out of date.
Roundels are the circular stickers seen on the front and rear windows of London private hire vehicles.
They have become somewhat of a beacon on the streets of the capital and help many to identify a minicab.
These stickers have the vehicle reg and licence number, along with the date of when the licence is due to expire.
Once a licence has expired, the roundels are supposed to be removed and either replaced with updated renewed roundels, or if the vehicle is no longer used as a minicab, then no roundel should be displayed.
Keeping roundels on a vehicle which is not used for private hire could pose a safety risk to the public, as the vehicle may be misidentified.
The officers who ran the roadside checks have said the roundels have now been returned to TfL.