'Do Not Duplicate' Does Nothing. Here Is What Actually Works.

Somewhere in your building there is a key stamped DO NOT DUPLICATE, and whoever ordered it believed that stamp was doing something. It is not.

The phrase carries no legal force in Canada. It is a request. Any key cutter, hardware store or self-service kiosk can ignore it, and plenty do — the blank is a standard commercial blank sold by the thousand, and cutting it takes fifteen seconds.

Why the stamp fails

• It is not backed by legislation — no statute makes copying a stamped key an offence
• The blank is unrestricted and available to anyone who wants to stock it
• Self-service kiosks in retail stores do not read stamps at all
• Enforcement depends entirely on the goodwill of whoever is holding the key

What real key control looks like

Genuine key control rests on a patented keyway. The key blank itself is protected by an active patent, so it is not sold on the open market — it exists only within the manufacturer's authorised dealer network. Nobody can cut a copy, because nobody else can legally obtain the blank.

On top of that sits the administrative half: an authorisation list. You name the people entitled to order keys for your system. A request from anyone else is refused, and every order that is filled is logged against a signature.

The three things a restricted system gives you

• Exclusivity — the blank cannot be obtained outside the authorised dealer network
• Accountability — every key cut is recorded against the person who authorised it
• Certainty — when a key goes missing, you know it is one key, not an unknown number of copies

The security bonus

Restricted keyways are almost always high-security cylinders as well, which means the same upgrade brings pick resistance, bump resistance and drill resistance. Standard commercial pin tumbler cylinders can be picked by anyone with modest practice and inexpensive tools; a sidebar or rotating-element cylinder is a different proposition entirely.

What it costs, and where to spend it

High-security cylinders cost several times a standard cylinder, which is exactly why we recommend deploying them selectively rather than everywhere. In most buildings the list is short: perimeter doors, master-keyed cylinders, cash handling, controlled substances, server and records rooms.

Interior offices and low-risk storage rarely justify it. A locksmith who tells you every door in the building needs a restricted cylinder is selling, not advising.

Where to start

If you do not know how many copies of your front door key exist, the honest position is that you have no key control at all. The remedy is a rekey onto a restricted keyway plus a fresh issue register: it draws a line under everything unknown, and from that moment every key in circulation is one you authorised and can account for.