A standard key can be copied at any hardware store or big-box retail counter for a few dollars, no questions asked. For a property manager, that’s the entire problem with standard locks: once a key is issued, there’s no way to know how many copies exist. A restricted keyway system exists to close that gap.
What a Restricted Keyway Is
A restricted keyway is a key blank design that isn’t sold to the public. The physical shape of the blank is unique and patent-protected, and it’s only available through dealers who are specifically authorized by the manufacturer to order and cut it. A hardware store, a home improvement retailer, or a general locksmith without that authorization simply cannot get the blank, the manufacturer won’t sell it to them.
That single fact is what makes the system work. If a tenant, employee, or contractor takes their key to get a copy made somewhere unauthorized, the counter clerk can’t fill the order. There’s no blank to cut. The only way to get a legitimate duplicate is through the authorized dealer who controls that keyway.
Patent Protection
The uniqueness of a restricted keyway blank is protected by patent, which is what legally prevents other manufacturers from producing a compatible blank and selling it openly. Patents on key blank designs run for a set term and eventually expire, at which point the design can potentially become available more broadly. Property managers evaluating a restricted keyway system should ask their dealer about the current patent status of the specific keyway being proposed.
Key Blank Control
Beyond the patent itself, restricted keyway systems build in a tracking layer that standard keys don’t have. The manufacturer tracks every blank that ships, each blank is serialized, and the authorized dealer signs for every order placed. That creates an audit trail from the factory to the building: a specific number of blanks were shipped, to a specific dealer, for a specific customer. It’s the difference between “we think we know how many keys exist” and “we can prove how many keys exist.”
The Two Systems Pro Locksmith Supplies
Pro Locksmith LLC is an authorized dealer for both Medeco and Mul-T-Lock, two separate high-security, restricted keyway systems. Both are available only through authorized dealers, which is the point: most locksmiths, including many who advertise “high-security” locks, cannot order or cut restricted blanks for either system because they haven’t been authorized by the manufacturer to do so.
Medeco is a high-security restricted keyway system built around patent-protected key blanks that are cut and issued only through authorized dealers.
Mul-T-Lock is a separate high-security restricted keyway system, also built around patent-protected blanks available only through authorized dealers.
Both systems provide the same core protections: a patent-protected key blank shape, manufacturer-level serialized tracking, and dealer-only cutting. Neither is a “better” or “worse” version of the other, they’re two distinct engineering approaches to the same problem, and the right choice for a given building depends on the property’s existing hardware, the architecture of its master key system, and its specific security requirements. A property already running one system’s cylinders is usually best served by staying within that system; a property starting from scratch has a genuine choice between two well-established options.
Key Control Documentation
A restricted keyway system comes with paperwork that a standard lock never generates. New systems typically include a letter of authorization establishing who’s permitted to order keys for that system. From there, the authorized dealer maintains ongoing records of every key cut and issued. Building management can request a key log at any time showing exactly who holds a key to a given door, something that’s simply not possible with a lock that anyone can duplicate at a retail counter.
When a Building Should Upgrade
A few situations point clearly toward upgrading to a restricted keyway:
- The building currently uses standard Schlage or Kwikset key blanks. These are widely available and can be copied at any hardware store, which means the building has no real way to control how many keys exist.
- Keys have gone unaccounted for. If a key has been lost, not returned, or its whereabouts are unclear, every lock on that keyway is effectively compromised until it’s rekeyed.
- After tenant turnover. A departing tenant’s keys should stop working. A restricted system with proper key control makes it possible to know exactly which keys need to be collected or invalidated.
- After staff changes. Same logic as tenant turnover, applied to employees who had access to secure areas.
- After a security incident. Any break-in, theft, or unauthorized entry is a signal that the current key control, or lack of it, has already failed once.
Why This Matters for Property Managers Specifically
If a standard key gets copied without authorization and that copy is later used in a crime, a property manager who did nothing to control key duplication can be exposed to a negligence claim, the argument being that reasonable security measures weren’t in place. A restricted keyway system directly addresses that exposure. With serialized tracking and a documented key log, a property manager can show exactly how many keys exist and who holds each one. That’s a materially different position to be in than “we don’t know how many keys are out there.”
What Happens Without Key Control
Most buildings that end up switching to a restricted keyway aren’t planning ahead, they’re reacting to a problem that already happened. A common pattern: a property has run on standard Kwikset or Schlage cylinders for years, tenants have come and gone, and at some point management realizes nobody actually knows how many keys are in circulation. Maintenance staff have copies. A departed tenant may or may not have turned theirs in. A contractor was given a key for a single job three years ago and was never asked for it back.
At that point, the building has two options. Rekey everything on the same standard system and hope the same drift doesn’t happen again, or move to a restricted system where every future key is tracked from the day it’s cut. The second option costs more at the point of installation. It’s also the only one of the two that actually solves the underlying problem, because the standard system will drift out of control again for the exact same reason it did the first time, anyone with a key can get a copy made anywhere.
Master Key Systems and Restricted Keyways
Many commercial and multi-tenant properties run a master key system, a hierarchy where a master key opens every door, sub-masters open groups of doors, and individual change keys open only their assigned door. This kind of system is only as secure as its weakest key. If a single change key on a standard keyway gets copied without authorization, the holder of that copy still can’t get into other units, but the building has still lost track of a legitimate key. On a restricted keyway, that same change key can’t be duplicated by anyone outside the authorized dealer relationship, which means the master key hierarchy stays intact and verifiable at every level, not just at the top.
Building out or reworking a master key system is also where the choice between Medeco and Mul-T-Lock tends to get decided. Both manufacturers support multi-level master key architectures. The deciding factor is usually what’s already installed, since matching new cylinders to an existing system’s architecture is more practical than mixing two restricted platforms in the same building.
What to Ask a Dealer Before Upgrading
A property manager evaluating a restricted keyway upgrade should expect straight answers to a few questions: Who else is authorized to order keys for this system besides the current dealer? What documentation will we receive showing who holds which key? What happens if our authorized dealer relationship ends, can another authorized dealer for the same manufacturer service the system, or are we locked to one vendor? A legitimate authorized dealer should be able to answer all three without hesitation, because the manufacturer’s own dealer agreement addresses each one.
Sources: Medeco product catalog; Mul-T-Lock product catalog.
Pro Locksmith: Authorized Dealer for Both Systems
Pro Locksmith LLC is an authorized dealer for Medeco and Mul-T-Lock, serving commercial properties throughout Broward County and Miami-Dade, including Fort Lauderdale, Hollywood, Pembroke Pines, Davie, Pompano Beach, Coral Springs, and Miami. The company is licensed and insured, pricing is flat-rate and quoted up front, and a certificate of insurance is provided for commercial property managers.
To discuss which restricted keyway system fits your building, call Pro Locksmith LLC at (954) 406-8266.
Restricted Is Not Automatically High-Security
Two terms get used as if they mean the same thing. They do not.
- A restricted keyway controls who can get a key blank and who can cut a copy. Its job is duplication control.
- A high-security cylinder is built to resist picking, bumping, drilling, and other attacks on the lock itself. Its job is resisting forced or covert entry.
Some products offer only one of these. A restricted blank can be used in a cylinder with ordinary internal pins, which stops copying but does little against a skilled attack on the lock. The systems described above combine both protections. When comparing proposals, ask which of the two the product offers, and whether the cylinder carries a recognized high-security rating in addition to the restricted blank.
Levels of Restriction
Not every restricted keyway is restricted the same way. The level of control depends on how the manufacturer distributes blanks:
- Factory-level restriction means the manufacturer controls every blank and ships only to authorized dealers for specific registered customers.
- Dealer-exclusive keyways are assigned to one dealer in a region, so no other dealer in that area can order that particular blank.
- Customer-exclusive keyways go further, assigning a specific keyway to a single property or organization.
The tighter the restriction, the stronger the control, and usually the more paperwork is involved each time a key is ordered. A large property with its own security staff may want the tightest level. A small building may be well served by a standard restricted keyway with signed authorization.
Photos and Online Key Copying
A newer reason to consider restricted keys: many standard keys can now be copied without ever handing over the physical key. Self-service kiosks in stores can duplicate common keys in moments, and some online services cut keys from a photograph. A tenant, a guest, or anyone who briefly gets hold of a key or a clear picture of it can have a working copy made without the property manager ever knowing.
Restricted blanks are not available to kiosks or general copy services, so those shortcuts do not work. For properties where keys are shared among staff or tenants who come and go, that alone can justify the change.
How Tenants Get Keys Under a Restricted System
A restricted keyway changes the process for everyone, and it helps to set expectations with tenants in advance. The usual flow looks like this:
- The property owner or manager designates who is authorized to request keys. That list is kept on file with the authorized dealer.
- When a tenant needs another key, the request goes to the manager, not directly to the locksmith.
- The manager approves the request and passes it to the dealer, along with the key number or code.
- The dealer cuts the key, records it, and releases it to the authorized person.
- The key log is updated with who received the key and when.
It takes a little longer than a trip to the hardware store, and that is the point. Explain the process at lease signing so tenants are not surprised the first time they want a spare. Many managers also address key requests and duplication in their lease forms. Have your attorney review that language, since lease terms vary with the property and the tenancy.
Which Doors to Put on Restricted Keys First
Few properties convert every lock at once. A sensible order of priority for a multi-tenant or commercial building:
- Perimeter doors: building entrances, rear exits with outside cylinders, and service doors.
- Master-keyed or shared-access doors: mechanical rooms, electrical rooms, roof access, and storage.
- Sensitive interior doors: management offices, records rooms, and any room holding cash or valuable equipment.
- Tenant or unit entry doors, often at turnover, one unit at a time.
Converting at turnover spreads the cost out and avoids disrupting occupied units. Over a few years, the whole property migrates to the restricted system without a single large expense.
Will My Existing Locks Accept Restricted Cylinders?
In many cases, yes. Commercial mortise locks, rim cylinders on exit devices, and many cylindrical lever locks accept replacement cylinders from restricted systems. Residential-style knobs and deadbolts vary more. Some accept compatible cylinders, and some need to be replaced. During a survey we identify each lock type and tell you which ones can take a new cylinder and which need new hardware. Changing only the cylinder, where possible, is usually the more economical path.
Counting Keys at Move-Out
The key log is only useful if move-out follows it. When a tenant leaves, compare the keys returned against the keys issued under that unit number. Because every restricted key is recorded, the count either matches or it does not. If it matches, the unit can be re-let with the same cylinder if you choose, or rekeyed as routine. If a key is missing, you know exactly which cylinders are exposed and can rekey just those, rather than guessing. Note the result in the log with the date, so the history of every cylinder stays complete. Over time, that history also shows which units or tenants lose keys most often, which is useful when planning where electronic access would pay off.
Condo and HOA Common Doors
Condominium associations and homeowner associations face the same copying problem on common doors: the pool gate, the gym, the trash room, the mail room, and the clubhouse. Residents move, rent out units, and hand keys to guests and contractors. Over time, an association can lose all track of how many keys to those shared doors exist. Moving the common doors to a restricted keyway, with keys issued only through the management office and recorded per unit, restores control. Some associations pair this with electronic access on the busiest doors, which is covered below.
What a Restricted Keyway Does Not Do
A restricted keyway is a strong tool, but it has limits worth understanding before you invest:
- It does not stop a key holder from lending their key to someone else.
- It does not tell you who used a key or when. For that you need electronic access control with individual credentials and an audit log.
- It does not make an unreturned key stop working. If a key is not recovered, the affected cylinders still need to be rekeyed.
- It does not help if the key log is not kept up to date.
The system gives you control of duplication. The property still has to manage issuance and returns.
Combining Restricted Keys With Electronic Access
Many properties use both. Electronic access on the doors people use most, such as main entrances, amenity doors, and staff entrances, gives an audit trail and instant credential removal. Restricted mechanical keys cover the rest, including the mechanical override cylinders on the electronic doors. Those override keys are some of the most important keys on the property, because they bypass the access control system entirely. Keeping them on a restricted keyway means the one key that gets around the electronic system cannot be quietly copied.
Commercial Tenants and Warehouses
Warehouses, flex spaces, and retail tenants often have more keys in circulation than anyone realizes: shift supervisors, delivery drivers, cleaning crews, and alarm response contacts. A restricted system is especially useful where the keys control access to inventory. Pair the change keys with a clear rule that keys are returned at the end of employment, and a quarterly count of keys against the log.
We set up restricted key systems for commercial and multi-tenant properties across Broward County and Miami-Dade, north through Boca Raton and Delray Beach, and for commercial clients up to West Palm Beach.