There are no official published lists of Master Locks combinations, but the lock makers site offers two options for recovering combinations for locks with serial numbers. The lock´s owners can take the lock to the supplier where it was purchased and have them call Master Lock or submita "lost combination" form that has been notarized to verify the owner of the lock. Once the form is received, the second process takes six weeks to finalize.
To increase long term security, Master Lock discontinued the use of serial numbers imprinted on locks sold at retail outlets. In response for the need for a tracking system for combinations, a registry has been set up as a secure online storage vault for lock passwords called Master Lock Vault. The service is free and once signed up, gives users a range of applications relating to securely storing and backing up sensitive data and files. For security reasons, Master Lock will not provide combinations to locks that are attached to anything.