The MIB has written to all 3,000 policyholders giving them a two week deadline to provide the required information to their brokers or insurers.
After the deadline expires, the MIB will forward details of those that have not responded to the police for prosecution via the Crown Prosecution Service.
"We have given rogue policyholders their final warning," said Neil Drane, head of the Motor Insurers’ Information Centre at the MIB. "Together with the Department for Transport, we will be asking the police and Crown Prosecution Service to take action against these organisations as quickly as possible."
Earlier this year, the MIB revealed that 14,000 open cover policies, which collectively account for around 200,000 vehicles, were not included on the Motor Insurance Database.
"We’re pleased that so many policyholders heeded our earlier warning, but we remain determined to pursue those organisations that have flouted the law for so long. If it requires substantial fines to bring about the necessary change in behaviour, then so be it," said Drane.
The MIB also warned that the likelihood of offending commercial vehicles being identified by police is likely to rise if the policyholders do not take action.
"The increased use of Automatic Number Plate Recognition (ANPR) cameras by police forces across the country has resulted in more than 30,000 uninsured vehicles being seized in the UK this year already," added Drane.
"However, police operations are also stopping fleet drivers whose employers have not ensured that the correct insurance policy information appears on the Motor Insurance Database."
The UK has one of the highest levels of uninsured driving in Europe, which typically adds around £30 to the cost of premiums for honest motorists. An up-to-date and accurate Motor Insurance Database is essential to the police and MIB’s aim to bring the levels of uninsured driving down over the long term.