Northumbria police carried out almost 100 checks on door staff in Sunderland as part of a crackdown on unlicensed operatives but found the vast majority were complying with the law.
Police, along with local authority enforcement officers, the Department of Work and Pensions and officers from the SIA checked 97 door staff at 39 premises in the city centre.
Lucia Howland, SIA head of investigation.
Of the door staff checked three were given a warning notice for not displaying their licence, two licences were reported as missing, which was later confirmed, and a photocopy of one was supplied.
Chief Inspector Paul Orchard, of Sunderland Area Command, said: "It is encouraging that of the door supervisors checked only a very small minority were not displaying their licence badges.
"We work very closely with local bars, pubs and nightclubs in Sunderland city centre, as well as the local authority and SIA to ensure that the many people who visit and work in the centre at night can do so safely and without threat of crime and disorder."
Lucia Howland, SIA head of investigation, said: "I am very pleased with the outcome of Friday's operation. All of the door staff checked held valid SIA Door Supervisor licences and that demonstrates to the police and public that the door staff are professionals who are trained, qualified and fit for their role."