BUREN Super Slender / Micro-Rotor Automatic, "Planet-Rotor"

— The future the micro-rotor drew —

The idea of setting the rotor into the movement's mainplate.

It was a challenge that cut away thickness and redefined the construction of automatic winding.

The micro-rotor is a poem hidden inside a machine, and a quiet revolution that let a watch sit thinner against the body.

— Two brands, one idea —

At the end of the 1950s, an idea took root in the Swiss air at two places at once.

Buren and Universal Genève.

That they reached the same concept at the same time without knowing of each other may not have been coincidence, but a structural inevitability the era demanded.

— Micro-Rotor and Planet-Rotor —

The name "Micro-Rotor," marked by Universal Genève, became an emblem of beauty and innovation.

Buren's engineer Hans Kocher, meanwhile, wanted the name "Planet-Rotor."

That name was forgotten as time passed.

Naming is also a way of governing memory.

In 1954, Hans Kocher applied for patent CH329804A.

That fact, rarely spoken of, lies quietly buried in watch history.

— Who the invention belonged to —

Remarkably, Universal Genève lost a patent dispute with Buren.

Buren then actively licensed the technology to other firms on the strength of its technical advantage.

Universal Genève was no exception: for the mechanism fitted to the Polerouter it was obliged to pay Buren a licence fee on every single movement.

— Where the patent went —

Universal was later granted a patent of its own, in 1958.

Given that Buren clearly filed first, a commercial compromise seems likely — though no evidence survives to confirm it.

More than half a century on, a small rotor still turns quietly on the wrist.

Perhaps its real meaning is something only the movement needs to know.

Enjoy at your own wrist a romance of history that reaches across the decades.

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