Switzerland (original crown patent); England (Rolex's own GB patents) · Swiss patent for the screw-down crown registered 30 October 1925 (No. 114948); corresponding British patents registered by Rolex in 1926 (commonly cited as GB 260,554 for the crown and GB 274,789 for the waterproof case), with further improvement patents through the following years
Rolex Oyster Waterproof Case and Screw-Down Crown
Partially verifiedThe Oyster case established waterproof/dustproof construction as a mainstream, marketable feature of the wristwatch rather than a rare specialist novelty, and underpins the case architecture of most modern sports and tool watches.
Paul Perregaux and Georges Perret registered a Swiss patent for a screw-down winding crown in 1925; Hans Wilsdorf recognised the commercial potential, acquired rights connected to the design, and had Rolex register corresponding and further-developed patents in Great Britain covering both the screw-down crown and a screw-back, screw-bezel waterproof case.
The resulting Rolex 'Oyster' case, launched in 1926, combined the screwed crown with a screwed case back and bezel so that the whole case, not just the crown, resisted water and dust ingress; case backs of early Oyster watches list the relevant Swiss and British patent numbers.
This entry follows patent numbers as they are commonly reported in specialist horological research (including collector and archival sources); researchers should confirm exact numbers and dates against the UK Intellectual Property Office historical register and the Swiss Federal Institute of Intellectual Property before treating any single number as beyond doubt.
The crown screws down onto a threaded tube to seal the case.
Background
To keep dust and moisture from reaching the movement under the dial and crown, a third-party casemaker produced a waterproof and dustproof wristwatch for Rolex in 1926, named the Oyster. The watch featured a hermetically sealed case designed to allow for winding and time adjustment while remaining protected from water ingress. To demonstrate its reliability, the company famously showcased these watches submerged in aquariums. The brand's promotional efforts included equipping swimmer Mercedes Gleitze with the watch during her 1927 English Channel crossing attempt.
Written from the encyclopedia entries listed under Sources; each statement was checked against the cited text.
How it works
- Rolex acquired the Perregaux–Perret screw-down crown patent, added a clutch, and combined the screwed crown with a threaded case back and bezel.
Later history
- The Oyster watch served as the foundation for the subsequent Oyster Perpetual series released in 1931.
- Rolex presented the 1926 Oyster as the first reliable waterproof wristwatch case based on a screw-down crown, but Depollier's case had been patented eight years earlier.
- The invention was preceded by other waterproof watch systems such as the Submarine Watch by Tavannes.
How to verify this yourself
Confirm exact patent numbers and grant dates directly against the UK Intellectual Property Office's historical patent records and the Swiss Federal Institute of Intellectual Property's register, since numbers circulating in collector literature and case-back markings should be cross-checked rather than assumed correct from a single secondary source.
Manufacturers known to have used it
- Rolex
- Tudor (related company)
- widely imitated screw-case architecture across the industry from the later 20th century onward
Photographs
Photographs are illustrative examples of the type, not necessarily the exact object described. Verify details against the source file page.
Sources & references
- Rolex, Wikipedia (English), retrieved 2026-10-28 (text CC BY-SA 4.0)
- Boettcher, D., published research on the history of the Rolex Oyster and screw-down crown (vintagewatchstraps.com)
- Cutmore, M., Watches 1850–1980
- Rolex published history of the Oyster
- Dowling, J. & Hess, J., The Best of Time: Rolex Wristwatches
Where sources disagree, the disagreement is stated rather than resolved silently.