Patek Philippe had an active 2024, not just because of the launch of the ref. 5330G World Time with Date, a massive collection of Rare Handcrafts, and of course the Cubitus. But equally notable was the announcement of updates to the Patek Philippe Seal.

Buried on the last page of its 2024 Watches & Wonders brochure was some fine print about some updates to the brand’s internal certification that superseded the longstanding Poinçon de Genève in 2009. The updates applied to two things that watch enthusiasts love to argue about: water resistance and rate accuracy.

Officially rated to 30 m and -1/+2 seconds a day

Initial thoughts

Water resistance is never far from the minds of watch geeks, so it’s no surprise that this is dominated the discourse when the announcement was made earlier in the year; the idea of a Nautilus rated to just 30 m was concerning to many. Apparently even the fact that the watch itself was unchanged did little to quiet the nerves.

Perhaps because people enjoy the opportunity to punch up, far more attention was paid to the issue of water resistance than the meaningful updates made to timekeeping testing and certification, which cement Patek Philippe’s position as the leader in high-end mechanical timekeeping at scale.

The cal. 240 PS CI J LU of the Cubitus ref. 5822P also features a Spiromax hairspring, clearly visible

Thirty meters

But let’s get water resistance out of the way. Patek Philippe now guarantees all of its water-resistant watches to the same rating of 30 m. According to Patek Philippe, this was done to make it easy for owners to understand the utility of their watch, and to reflect real-world use. The 30 m rating encompasses “washing… hands, showering, bathing, swimming and other aquatic activities, including diving to a depth of 30 m”.

(Watches that are not water resistant, like repeaters and the Sky Moon Tourbillon, remain non-water-resistant.)

For years, confusion has swirled on watch forums and in private message groups about how much water resistance is required to take a watch underwater. Of course, few people actually take their watches underwater; what people want is a sense of safety, and a feeling that the delicate movement inside their watch is protected as much as possible.

Perhaps for this reason, a few rules of thumb have emerged that emphasise a sizeable margin of error. Thirty meters of water resistance is what is often considered merely “splash resistant” while 50 m is considered the bare minimum for swimming in a pool.

The Nautilus ref. 5811/1G, now rated to 30 m but still a sports watches

So I understand why Patek Philippe saw the need to provide clarity on this topic. By opting to have move away from the typical rating scale and adopt a minimum threshold that should exceed the demands of any real-world scenario, the brand is seeking to assure customers that its watches, sports or dress, are robust, even if rated to merely 30 m. In other words, this should be seen as Patek Philippe having a great deal of confidence in its dress watches.

Patek Philippe is not the first brand to do something like this. Omega also guarantees all its watches to the respective stated depth, even those rated to 30 m. In fact, Omega specifies “a watch that is water resistant to 30 metres can be worn for swimming at depths of up to 30 metres underwater for extended periods without restriction”. Omega has, however, stuck to a graduated scale, certifying its sports watches to even greater depths.

Go ahead, take it for a swim

Minus one to plus two seconds per day

Then there’s the matter of the new standards for rate accuracy, which are industry leading. The standards vary by the specifics of the movement, but to keep things simple, any Patek Philippe with an overcoil hairspring, tourbillon, or Spiromax (silicon) hairspring is certified to stay within -1 and +2 seconds per day.

For context, COSC certification requires precision of -4 to +6 seconds per day, the Master Chronometer standard (originally launched by Omega but now employed by Tudor as well) is 0 to +5 seconds per day, and even Rolex’s vaunted Superlative Chronometer standard allows for a range of -2 to +2 seconds per day.

Only one other production watch is certified to a more stringent standard than that of the Patek Philippe Seal: the Omega Speedmaster Super Racing, which is rated to 0 to +2 seconds per day.

But the Speedmaster Super Racing is just one singular reference among thousands in the vast Omega catalogue, and the model is produced in limited numbers (at least by Omega standards). Since Patek Philippe has moved to install Spiromax hairsprings in most of its watches, the brand is certifying this level of performance across tens of thousands of watches per year – about 72,000 according to Thierry Stern – a remarkable achievement.

The cal. 240 HU C in the ref. 5330G

And while Patek Philippe credits much of this performance to the superior characteristics of silicon hairsprings, it’s worth noting that the brand adjusts its overcoil-equipped watches and tourbillons to the same standard. While these account for a comparatively small part of the brand’s production, it shows an ongoing commitment to the highest ideals in watchmaking.

The small but mighty cal. R TO 27 PS QR in a ref. 5016, with a traditional metallic overcoil hairspring inside the tourbillon

Rewind

The Patek Philippe Seal was introduced in 2009, and quickly replaced the famed Poinçon de Genève (literally the “Geneva Seal”) on the brand’s movements. Patek Philippe had been a steadfast proponent of the Poinçon de Genève since it was introduced in 1886, so this change was received with some concern at the time. Given the conflict of interest inherent in any kind of self-certification process, there was apprehension that quality standards would soon fall.

The famous Geneva seal on a 1920s Patek Philippe pocket watch

Fortunately, these concerns were overblown. For one thing, the Poinçon de Genève is not all that difficult to achieve; its most stringent requirement is geographic, namely the need to make the watch within the canton of Geneva.

Both prior to and after the adoption of the Patek Philippe Seal, the quality of the brand’s watches far exceeded the standards required by the Poinçon de Genève. Many industry insiders believed  Patek Philippe scrapped its use of the seal for the opposite reason: because the quality and reliability of Poinçon de Genève-certified watches made by other brands was noticeably subpar.

The cal. R 27 PS of the ref. 3979 that bearing the Poinçon de Genève on the balance cock

Historically, only a few brands could apply for the Poinçon de Genève, which was dominated by Patek Philippe and Vacheron Constantin. But things started to change in the 1990s, when Gerald Genta, Roger Dubuis, and Chopard began making watches that qualified for the seal.

In the years that followed, particularly in the exuberant period before the 2008 financial crisis, brands that were traditionally located far from Geneva got into the mix. Amongst the entrants at the time was Cartier, which qualified for the seal by having its tourbillon watches produced in a corner of the Roger Dubuis manufacture in Geneva. More recently, Louis Vuitton has applied the seal to its highest-end models thanks to its La Fabrique du Temps manufacture in the city’s suburbs.

The GS 36‑750 PS IRM in the ref. 6301P grande sonnerie, showing off the Patek Philippe Seal.

Differentiating

In my view, it was necessary for Patek Philippe to abandon the Poinçon de Genève. The brand has always tried to maintain its leading position in the industry, and by adopting its own standard it distanced itself from peers and avoided the perception of a false equivalency between a Patek Philippe and another bearer of the Poinçon de Genève. Looking back at some of the atrocious pieces that have qualified for the Geneva hallmark, I believe Patek Philippe’s decision to adopt its own standard has been vindicated.

This update to the Patek Philippe Seal does much the same thing. The new unified water-resistance rating says that the brand is not interested in competing in the spec sheet, but remains willing to stand by its watches to their stated depth. Furthermore, the new criteria for rate accuracy are a testament to the brand’s mastery of chronometry, developed over decades of observatory competitions and enhanced by its early embrace of silicon.