The is a restricted key way
A restricted key way is a key that cannot be copied easily. Examples of these are Medico, schlage Primus, multi-lock and Assa. There are many other private brands that locksmiths use that the keys are proprietary to them.
These locks and their matching keys are very difficult to be duplicated. The advantage to a business is that if an employee returns the key it could not have been copied. This saves the business the cost of having their locks rekeyed each time an employee leaves.
This should not be confused with do not duplicate keys. Locksmiths currently sell keys that are marked do not duplicate that are actually exact copies of this schlage or kwikset keys you have in your pocket. Although these do not duplicate keys are a deterrent to having the keys copied, and most big box stores or hardware stores will not copy them, they are able to be copied easily. Of course the employee may not be aware of this.
However, a true restricted key way cylinder or lock is restricted to who may get additional keys. Usually, replacement keys are purchased from the locksmith that installed the locks with proper identification. With some of these you are given a card, similar to a credit card and without it no other keys can be obtained. We have had many homeowners move into a house with Medico or similar locks on it and were unable to obtain extra keys because they were left no cards for the locks.
These all orphaned locks can not get additional keys, but in some cases are able to be rekeyed to the key way of the new locksmith. This is not an inexpensive venture.
Some of the restricted key way locks are impossible to pick and bump. The majority of thieves breaking into your home no longer try to pick a lock instead they bump them. We’ve explained lock bumping in another article. Without a key to fit into the key way, due to it being restricted they are physically impossible to be bumped. And due to side bars and some of them their impossible to be picked.
The biggest asset of the restricted key way is that the employees can not get keys made from the key that was issued to them.
The way an employer would issue these keys is to explain to the employee these keys are worth $200 each. I’m not going to ask for $200 in advance, but should you fail to read turn these keys upon your departure we will deduct $200 from your last check. By doing this most employees returned the key and the store owner is save the expense of having a locksmith, and Rekey his locks.