Medeco and the key you couldn't copy
The cylinder Roy Spain carried to the US Patent Office on April 17, 1968 looked unremarkable from the outside — standard door lock, brushed brass, the sort of thing a hardware store displays next to the paint chips. What was different was inside: every pin was ground to a chisel point, and the key that opened it cut not just at depths but at angles.
Spain had been working the problem since the mid-1950s in a basement workshop in the Cave Spring area of Roanoke County, Virginia, where he and a few partners ran a small machine shop they called the Mechanical Development Company. The standard pin-tumbler lock — barely changed since Linus Yale Jr.'s 1865 cylinder — worked on a single axis: lift every pin to the right height and the barrel turns. Spain’s insight was that this left an entire dimension unused. His key cuts were angled, some slanting left, some right, so that each pin when lifted also rotated a precise number of degrees. A secondary locking bar called a sidebar would not retract until every pin had reached the correct height and the correct angular orientation simultaneously. With six double-action pins, the possible combinations exceeded two million (Wikipedia).
Patent 3,499,303 was granted on March 10, 1970, listing Spain, Paul A. Powell, Roy N. Oliver, and E.C. Flora as co-inventors. The company took its name as a compression of Mechanical Development Company: Medeco, which has the sound of a government agency and the footprint of a basement shop.
Spain was not shy about what he had built. As a promotional exercise, he offered $50,000 to anyone who could pick the lock. Hundreds tried. One New York City detective eventually succeeded — once. The challenge, it turned out, required the feat to be repeatable. The detective could not do it a second time. Medeco kept the prize money, and the detective was shortly afterward hired as a Medeco sales representative, which suggests Spain understood that nearly losing a picking challenge counts as winning it (en-academic.com).
The more consequential innovation was not the picking resistance. It was key control. Medeco’s utility patents covered not just the cylinder but the key blank itself — a steel profile no other manufacturer could legally reproduce. New keys could only be cut by an authorized dealer who was required to check identity first. In an era when any hardware store would copy most keys on request, this was a different category of security: not a stronger door, but a shorter list of people who could open it. By the mid-1970s the U.S. government was specifying Medeco cylinders for embassies, military armories, and federal buildings; banks and prisons followed. Hillenbrand Industries acquired the company in 1983; ASSA ABLOY, the Swedish lockmaker, took it over in 1998. The manufacturing facility never left Salem, Virginia (PRWeb).
Spain’s lock has since acquired software. The question it was built around — not can you pick this, but can you prove you’re authorized — is the question every access control system is still trying to answer.
Sources
- Medeco — Wikipedia — Founding history, the angled pin-tumbler mechanism, patent number, key control concept, ownership changes.
- Medeco — en-academic.com — Patent filing date (April 17, 1968), the $50,000 picking challenge and detective anecdote, Mechanical Development Company origins.
- Medeco Security Locks Celebrates 50 Years — PRWeb — Founding in Salem, Virginia; government adoption; manufacturing continuity.