While my penchant for mid ’90s New York grime-style rap, which reached its apogee in 1994 with the release of the Notorious B.I.G.’s transcendent Ready to Die, is well documented, there is one other musical genre which has unexpectedly intrigued me. And that is Victorian-era comic opera, specifically the works of master of the libretto W.S. Gilbert and composer extraordinaire Arthur Sullivan, without whom there could be no Irving Berlin, no Oscar Hammerstein and no Andrew Lloyd Webber. Their seminal creation is the absurdist masterpiece, The Pirates of Penzance, with the unforgettable songs, “With Cat-Like Tread” and “Modern Major-General”. As an aside, one can make the argument that the blistering hyper-alliterative verbal arrangement of “Modern Major-General” is one of the earliest precursors to rap and bears a startling sonic resemblance to Blackalicious’ “Alphabet Aerobics”. The Pirates of Penzance’s plot is narrative ingenuity at its best.

A clever plot device of the leap year is employed in The Pirates of Penzance
A clever plot device of the leap year is employed in The Pirates of Penzance

It centres around Frederic, the hapless young protagonist who is indentured to a group of pirates until the age of 21. However, the pirates who don’t want to lose their young ward come up with the clever lie that he was born on the leap day February 29th and as such, only celebrates his birthday once every four years, and therefore must remain with them until he is 84. I remember muttering to myself, “Oh, nefarious machinations,” as I turned the pages of the script at the precocious age of nine, which intrigued me to discover why it is that the leap day/leap year existed at all.

It turned out this was all down to a pope named Gregory XIII who in 1582 instituted the Gregorian calendar, which corrected faults in the Julian calendar. The issue essentially was this: the calendar year where time is divided into 24-hour days, seven days a week and 30 or 31 days a month with 28 days in February for a total of 365 days is actually shorter than the solar year, which is how long it takes the Earth to revolve around the Sun. This is actually 365 days, five hours, 49 minutes and 16 seconds to be precise. To compensate for this, Pope Gregory XIII added the day of February 29th once every four years. But this in turn creates a slight overage so that every 100 years, though divisible by four, the leap day is left out. Every 400 years, it is put back in. Still with me?

First page of the papal bull issued by Pope Gregory XIII that decreed the Gregorian calendar into existence
First page of the papal bull issued by Pope Gregory XIII that decreed the Gregorian calendar into existence

OK, so clearly, to put a perpetual calendar mechanism which would keep track of the date, day, compensate for the shifting 30/31-day cycle of the months, know when February had 28 days and know when it had 29 days, would be an act of horological badassitude in extremitas, correct? Well, it just so happened that an English watchmaker named Thomas Mudge did just that in 1762. In 2016, that watch went up for auction and was purchased by none other than the most famous watch brand on the planet, Patek Philippe.

Earliest known perpetual calendar watch, created by Thomas Mudge in 1762. Image: Sotheby’s
Earliest known perpetual calendar watch, created by Thomas Mudge in 1762. Image: Sotheby’s

This was extremely fitting because in the annals of modern horology, there is no brand more synergistically associated with the perpetual calendar wristwatch. Patek Philippe was the very first to create a perpetual calendar wristwatch in 1925, the first to create a retrograde perpetual calendar wristwatch in 1937, and the very first to produce a perpetual calendar wristwatch in series in 1941 with the legendary reference 1526. It was the first to create a sweep seconds perpetual calendar wristwatch in 1944 with the reference 1591 and the first to serially produce this complication in 1951 with the reference 2497. It was also the first to create a self-winding perpetual calendar beginning in 1962 with the iconic reference 3448; it would take a full 16 years before another Swiss watchmaker could match this achievement. In addition, Patek was the first to create a perpetual calendar chronograph in 1941 and the first to create a perpetual calendar watch with leap-year indicator in 1975.

Patek Philippe ref. 1526
Patek Philippe ref. 1526
A unique Patek Philippe ref. 3448, with a leap year display instead of a moon phase shown on the subdial, circa 1975
A unique Patek Philippe ref. 3448, with a leap year display instead of a moon phase shown on the subdial, circa 1975

Today, Patek Philippe continues to be the unrivalled master of this complication with no less than three different systems for displaying the calendar information. The first is using the classic combination of two in-line apertures for day and date, combined with subdials for the remaining information. The second is using a full array of subdials. And the third is using a total of three in-line apertures for day, date and month, and featuring an instantaneous changeover of information. At the moment, this third format is only combined with complications such as a chronograph minute repeater as in reference 5208. As such, no other Swiss maison can claim greater legitimacy in the creation of perpetual calendar wristwatches, or possesses a more beautiful history with this extraordinary complication. The focus of this article is to detail Patek’s journey with the perpetual calendar, from its first watch to feature this mechanism to its most recent.

Patek Philippe ref. 5208P
Patek Philippe ref. 5208P

The Initial Forays

Patek’s very first perpetual calendar wristwatch dates back to 1925. But in reality, the movement for this watch goes even further back to 1898, when the maison made the movement to be housed in a women’s pendant watch. It is intriguing to imagine their thinking at the time. That this extraordinary complication capable of keeping time, date, day, month, year and even moon phase would appeal to a very specific female client. The watch went unsold and a quarter century later, this exceptional movement was re-cased in a beautiful yellow-gold wristwatch replete with hunter back and a large fluted crown. The 34.4mm-diameter case also featured stunning hand-engraved lugs, a tradition still associated with Patek to this day. The grand feu enamel dial of the watch was most likely turned 45 degrees from the original orientation of the movement — the pendant watch was probably intended to be worn crown up at 12 o’clock. As such, small seconds now appeared at nine o’clock and moon phase at three o’clock, while you could easily imagine them to be in the more traditional six and 12 o’clock positions. Date was told using a large centrally mounted hand off a red scale at the dial’s perimeter. The day-of-the-week subdial is located at 12 o’clock while the month subdial is at six o’clock. It is interesting to note that Patek would never repeat this design again. The watch designated number 97975 and which featured Patek’s 12-ligne movement was sold in 1927 to an American collector named Thomas Emery and today constitutes a historical treasure that is simply priceless.

World’s first perpetual calendar wristwatch, created by Patek Philippe in 1925
World’s first perpetual calendar wristwatch, created by Patek Philippe in 1925

In 1930, Patek followed up this halcyon achievement with a stunning cushion-shaped perpetual calendar watch which was a revelation from both a technical and aesthetic perspective. First, you will notice how the calendar information is clearly separated. Date is now contained for the first time within the six o’clock subdial, which it shares with a continuous seconds indicator. Day and month are at subdials at nine and three o’clock respectively, and that are pushed to the very edge of the dial for enhanced segmentation. The moon phase indicator is relegated to 12 o’clock. This watch features Patek’s 13-ligne movement using a Victorin Piguet ébauche. Interestingly, this watch also set the precedent for the many complicated cushion-shaped timepieces that would become synonymous with Patek Philippe, such as the 5950 split-seconds chronograph and the perpetual chrono reference 5020, as well as the current collection’s stunning calibre 240-driven ultra-thin perpetual calendar reference 5940.

In 1937, a mere five years after the extraordinary Stern family took ownership of Patek Philippe, the firm once again re-entered the world of the perpetual calendar wristwatch, this time with an utterly unique and singularly animated timepiece designated the reference 96. This was the first Patek wristwatch to feature twin in-line apertures on the dial, on either side of the cannon pinion, for day and month. Date is told off an inverted arc that sweeps dramatically across the top half of the dial and is read from a retrograde hand. Meaning that at the stroke of midnight on the last day of each month, it jumps instantly back to the number “1” corresponding to the first new day of the next month. Phase of the moon is relegated to six o’clock. This watch featured Patek’s 11-ligne movement made from a Victorin Piguet ébauche. This stylised and dynamically formatted retrograde perpetual calendar would become a staple at Patek many years later with the reference 5050 watch launched in 1993.

Patek Philippe created another first with the ref. 96 by fitting a retrograde perpetual calendar within a wristwatch
Patek Philippe created another first with the ref. 96 by fitting a retrograde perpetual calendar within a wristwatch

The First Serially Produced Watches

Ref. 1526

The first serially produced perpetual calendar. Launched in 1941 and made in 210 examples over 12 years

Ref. 1526

1941 will forever be remembered as one of the seminal years in watchmaking history. At the behest of Charles Stern, Patek Philippe launched what are to this day two of the most legendary timepieces in horological history. The first is the reference 1518, the world’s first serially produced perpetual calendar chronograph. The second is the reference 1526, the world’s first serially produced perpetual calendar. The 1526 was manufactured for 12 years, during which 210 examples of this mythical beast were created. The majority of these are in yellow gold with a small quantity made in rose gold, and one known piece made in steel. The watch featured a svelte, streamlined 34mm case. Beating inside was a manual-wind Victorin Piguet-based calibre 12-120 QP.

The 1526’s greatest contribution to the horological canon was the creation of the now-classic perpetual calendar format where the two apertures for day and month (first seen in the ref. 96) were elevated to take centre stage just below the 12 o’clock index. The cream enamel dial featured a highly legible combination of applied Arabic and dot indexes. Hands were large imperious dauphine-style units. This is the first instance in which date and moonphase indicator are combined into the subdial at six o’clock, which would forge the genetic underpinnings of the majority of perpetual calendar displays that would follow this watch. One of the reasons that the 1526 feels so clean is that the seconds hand has also been incorporated into the subdial at six o’clock, leaving a large expanse of beautiful clear dial.

Ref. 1526

There has always been some speculation as to what the Stern family was thinking to launch two such complicated models in the throes of the Second World War. But I’ve always thought it was precisely because of the pervasive bleakness that they wanted to inject some light and inspiration into the world with these technical marvels. Amazingly, these watches are still relatively affordable despite their rarity and historical significance. In 2016, a rare rose-gold version sold at Phillips for just SFr.150,000 while excellent condition watches still regularly sell for under US$100,000. Christie’s auctioned this pristine yellow-gold example in 2017 that eventually sold for just US$106,250.

Ref. 1526
Ref. 1527

Two watches made with 37.6mm cases, one featuring a chronograph and one without. Year of production, circa 1943

Ref. 1527 consists of two watches made with 37.6mm cases, one featuring a chronograph and one without, produced in 1943
Ref. 1527 consists of two watches made with 37.6mm cases, one featuring a chronograph and one without, produced in 1943
Ref. 1527 non-chronograph version
Ref. 1527 non-chronograph version

Around this time, Patek Philippe continued to experiment with some very interesting versions of the perpetual calendar. The first of these is the reference 1527 made between 1943 to 1944, which comprises of two perpetual calendar watches one with a chronograph and one non chrono, both with large Calatrava-style case. It should be noted that at 37.6mm, these cases were significantly larger than the cases of the 1518 at 35mm or the 1526 at 34mm. The perpetual chrono version of this watch was sold in 2010 at Christie’s. After much research to determine the provenance and rarity of this watch, it sold for US$5,708,833. The other non-chronograph version of the 1527 (featuring the calibre 12-120 QP) was made for and worn by none other than Patek’s president Charles Stern himself. Today this watch resides at the Patek Philippe Museum and we’ve included an image of it here.

Ref. 1591

Two watches made in 1944 with waterproof cases, luminous dials and hands. Forged the design underpinnings of the 2017 ref. 5320

Ref. 1591 in stainless steel, Christie’s 2007 auction
Ref. 1591 in stainless steel, Christie’s 2007 auction

In 1944, Patek Philippe created what is my single favourite perpetual calendar watch ever made. The reference 1591 was a highly audacious timepiece in that it combined the elegant functionality and technical innovation related to the perpetual calendar with a waterproof case, luminous hands and dial. Befitting its sporty nature, rather than a small seconds hand that shared the subdial at six o’clock as with the 1526, the 1591 featured a large centrally mounted seconds hand. Collectively, these elements expressed that this steel-cased timepiece was made for a sportsman that wanted to wear his complicated timepiece while engaged in all manner of vigorous activity some of which — as expressed by its luminous nature — may have been nocturnal. And indeed the man in question was reputed to have been an Indian Maharaja who had a penchant for polo and other sports. The movement was even protected from magnetism with a soft iron shield, as seen on many scientific watches of the era. The watch was imported for him by Patek’s India distributor Favre-Leuba and so magnanimous was the Maharaja in question that as the story goes, after his wedding, he gave the watch to the man who organised the festivities. Which is too bad as there were only two of these ever made, and while this one was steel, the other was in yellow-gold. The timepiece was sold by Christie’s in 2007 for the sum of SFr.2,513,000. The 1591 was recently a major design influence in the 2017 reference 5320, which borrows its dial and hands design from the unique icon. As with the 1526, the watches’ movement is the Victorin Piguet, now designated 12 SC for seconds centrale QP.

Refs. 2497 and 2438-1

Both are essentially the same watch, but the 2438-1 comes with a waterproof case and screw-down caseback. A total of 179 pieces made between 1951 and 1963

Ref. 2497
Ref. 2497
Ref. 2438-1
Ref. 2438-1

Launched in 1951, the reference 2497 was the first sweep seconds Patek Philippe perpetual calendar watch made in series. It was made for 12 years during which time 179 examples were crafted. Note that this number also includes reference 2438-1 (essentially the same watch but with a waterproof screw back). At first glance, the 2497 is more imposing at 37mm in diameter than the 1526 at 34mm diameter. The watches can be divided into two series. The first series is characterised by an alternating dot and Arabic markers dial and leaf hands very similar to those found on the 1526. In marked contrast, the second series features hash marks with sword hands. All watches are manual wind.

Because these are the first serially produced perpetual calendars with central seconds hands, both series feature a large visible seconds track around the perimeter of the dial. Because Patek had (temporarily) dispensed with the seconds hand at six o’clock, the indication for the date is now larger and significantly easier to read. For the first time, Patek also did away with the circular track framing the date, creating a much cleaner lower half of the dial. Because of the bigger size, better wearability and more contemporary feel of these watches, coupled with their greater rarity, the 2497 and 2438-1 watches sell for significant premiums over the 1526.

Ref. 2497

A rare rose-gold watch sold at Phillips for SFr.742,000 in 2017, while an ultra-rare white-gold watch on a white-gold Patek-stamped Gay Frères bracelet went for a hefty SFr.2,292,500. On average, good-condition yellow-gold watches are in the SFr.300,000–400,000 range. This was one of only three white-gold examples known to exist. Further, its gold bracelet with Florentine finish was factory-fitted, demonstrated by the small custom-made grooves near the watch head for easy access to the perpetual calendar’s correctors.

Ref. 2497 in rose gold, first series
Ref. 2497 in rose gold, first series
Ref. 2497 in yellow gold, second series
Ref. 2497 in yellow gold, second series

Birth of the Self-Winding Perpetual Calendar

In terms of their capacity to provide you with calendar information, automatically compensate for the shifting 30/31-day rhythm of the months, and even knowing which years to add a day to February, perpetual calendars are technical marvels. If they were dogs, they would be border collies with preternatural cognitive abilities capable of playing Frédéric Chopin’s Nocturnes, while holding discourse on James Joyce’s stream of consciousness masterpiece Ulysses, all while herding a multitude of sheep. But they have one drawback, and that is when they run out of power because you forget to wind them or they’ve simply been set aside for too long, it can be mildly arduous to reset all of their indications. This was evidently not lost on Patek’s president Henri Stern for beginning in 1962, Patek became the first maison to create a self-winding perpetual calendar called the 3448.

Before plunging into the minutia of the most famous of Patek’s perpetual calendars, let’s stop to look at its precursor, the manual-wind 3449. This model is one of the rarest in Patek’s history with only three pieces crafted in 1961. These can be identified with the individual serial numbers 799000, 799001 and 799002.

Ref. 3449
Ref. 3449

All of these are 37mm-diameter yellow-gold-cased watches with silvered dials. However, each of these watches has different lugs, leading many to believe that they were actually design experiments leading up to the eventual development and release of the 3448. The first watch, No. 799000, features a triple-stepped bezel and angular lugs. The second watch, the 001, features a double-stepped bezel and angular lugs. And the third watch, the 002, is in possession of a triple-stepped bezel combined with unique long straight lugs that are 1mm longer than the others.

This third watch also features a caseback engraved with the name of its owner, Geo. Poston, short for George Poston, a Texas real-estate developer who had purchased the timepiece for $5,550 from Linz Brothers, a jewellery firm in Dallas. In addition, his caseback is engraved with the French phrase “Qu’Hier Que Demain” or “More than yesterday, less than tomorrow”, which references a romantic poem by the French poet Rosemonde Gérard. Today this watch resides in the collection of none other than Mr Auro Montanari, otherwise known as John Goldberger. The movement is the 23-300Q, an ultra-thin manual-wind movement.

Ref. 3448

The first serially produced self-winding perpetual calendar wristwatch. Made from 1962 to 1981 with a total of 586 examples. The only one of its kind on the market for 16 years. The first watch with “Disco Volante” case designed by Antoine Gerlach. Also featured sharp futuristic lugs. Nicknamed “Padellone” for its 37.5mm diameter and relatively thin case. Two platinum watches made in 1997, long after the model was discontinued. Cases for the ’97 watches made by Jean-Pierre Hagmann

Ref. 3448
Ref. 3448

The 3448 is, simply speaking, one of the most iconic wristwatches of all time. It is the world’s very first self-winding perpetual calendar chronograph. And with its large perfectly round and thin UFO or “Disco Volante” shaped case, characterised by dynamically attenuated lines designed by Geneva case-maker Antoine Gerlach, it was also a timepiece that captured the design zeitgeist of its era, and was the wristwatch choice of pop culture icons the likes of Andy Warhol and Ringo Starr. It is somehow amusing to think of these complex Swiss watches being worn on the wrists of these luminaries as they boogied the night away at Studio 54.

It is in interest to note that the watch’s Disco Volante design, which features a partially recessed crown, could have made it quite challenging to manual wind, which would offer an additional explanation as to why the 3449 was never put into serial production. In any case, the 3448 is the 20th century’s most iconic perpetual calendar. Close your eyes and imagine a watch with this complication and the 3448 will immediately appear. It is Zen reductive cool to the extreme! The markers are now thin, elegant baton-shaped units while the minute track is a stunning series of tiny applied dot markers (in the first three series). The hands are clean, bold sword-shaped units. But where did the seconds hand of the watch go? The same seconds hand which somewhat cluttered the subdial on the 1526, and which took imperious centre stage on the 2497, has been altogether dispensed with in the pursuit of the ultimate act of horological minimalism to render the purest expression of the perpetual calendar.

Ref. 3448

The case is a wholly modern 37.5mm in diameter and complemented by sharp angular lugs which serve to focus attention on the large wide dial, and relatively thin sharply raked bezel and thin case, which motivated the Italians to bestow the sobriquet “Padellone” or “Frying Pan” on the 3448. The watch was made in a total number of 500 examples between 1962 and 1981, of which 100 are in white gold. There are a further two rose-gold watches. And there are two watches that were originally white gold but then modified with platinum cases made by Jean-Pierre Hagmann long after the model was discontinued. The story goes that Philippe Stern gave permission for this to be done to fulfil a special order in 1996 from what was clearly an extraordinarily important client. Of these two platinum 3448s, one is owned today by none other than watch industry legend Jean-Claude Biver. A platinum watch was sold at auction by Phillips in 2018 and achieved a price of SFr.1,092,500. Previous to this, a platinum 3448 was sold at Christie’s in 2009 with a winning bid of SFr.783,000. This seems actually like something of a bargain considering that immaculate-condition white-gold 3448 watches can hammer in the mid SFr.600,000 range.

The 3448s can be further divided by their dials into four distinct series. The first three series all used grand feu enamel dials, short applied gold baton markers and sword-shaped hands. They all featured applied gold pearls for the minute track. Let’s pause for a moment to express just how difficult it is to execute these types of dials. First, these stunning white dials need to be rendered with perfect uniformity and be printed with their date wheels and Patek Philippe signatures in the space just below the twin apertures. Then these delicate dials need to be pierced to accommodate the applied markers as well as each individual pearl for the minute track. This piercing is clearly visible in the close-up images of the second-series white 3448 offered for sale by Christie’s in 2016.

Ref. 3448, first series dial
Ref. 3448, first series dial
Ref. 3448, second series dial
Ref. 3448, second series dial
Ref. 3448, third series dial
Ref. 3448, third series dial
Ref. 3448, third series dial
Ref. 3448, third series dial
Ref. 3448, fourth series dial
Ref. 3448, fourth series dial

Series 1–3 can be distinguished from each other by the typography of the date ring, specifically the size of the numbers used for the date. The first-series watches, according to Christie’s, are made from 1962–66. The watches feature enamel dials with medium-sized print for the numbers in the date ring. Further, the date ring is generally formatted so that the numbers from “11” to “23” are inverted to aid in visibility, otherwise you would be reading them upside down. The dials are marketed “Swiss” with no sigma symbol on either side of this hallmark (the “sigma dial” only came later, being a 1970s initiative by the Association pour la Promotion Industrielle de l’Or, APRIOR, essentially the Swiss federation for gold, to enhance the value of mechanical watches by emphasizing the use of solid gold parts).

The second series made from 1965–73 has distinctly smaller and lighter printed numerals in the date ring. These numbers can appear either inverted or un-inverted, where they are not flipped from “11” to “23” and thus appear upside down. The Swiss hallmark can have the sigma symbol on each side (usually for post-1970 dials), referring to the use of gold indexes on the dial.

The third series made from 1971–78 is the same but now with distinctly larger numbers than the first and second series. It can have an inverted or un-inverted date ring and it will have a Swiss hallmark with the sigma symbols.

The fourth series made from 1978 to circa 1981. These are the easiest to identify because the dials are no longer grand feu enamel but modern brass dials that have been printed. Minute markers are no longer applied pearls but small printed hash marks. These watches also have the sigma symbols due to their gold markers. There have been some interesting one-off watches that have emerged in the lifespan of the 3448. One of these is a very intriguing white-gold 1974 ref. 3448 that appears to have been retrofitted later with a factory-original series-four luminous dial and luminous hands.

Of the four series, to my mind, the second series with its more restrained and subtle date ring is the most beautiful and integrates most perfectly with the 3448’s minimalist iconography. However, that’s splitting hairs as every one of these masterpieces is exquisite. All watches from the four series use the calibre 27-460 Q.

A Unique Piece and a Controversy

OK, so up until this point, all perpetual calendar watches while capable of adding the 29th to February on leap years had one shortcoming. And that was they had no display for where in the leap-year cycle you were, making adjusting your watch something of chore. Indeed, it would not be until the launch of the reference 3450 in 1981 that a regular production perpetual calendar watch would finally have a small aperture that would tell you where in the leap-year cycle you were. And it would only be in 1985, with the simultaneous launch of the 3940 perpetual calendar and the 3970 perpetual calendar chronograph, that you would have a full display for the cycle in a subdial.

Ref. 3450
Ref. 3450

However, as early as 1975, Patek Philippe had already devised a way to display this. And they did just that for a very unique 3448 that was gifted to a very special individual. Alan Banbery wrote the first officially sanctioned book on Patek Philippe (the second one was written by my dear friend Nick Foulkes) and was a former director at Patek. He is something of a legend in the watch industry. In 1975, Banbery received a very special 3448. This was a second-series yellow-gold watch dating to 1970 and characterised by its small date ring. But instead of the moon phase display, it featured for the first time a leap-year indicator. The inner subdial was divided into four quadrants, each representing a year in the four-year cycle. The upper right was delineated “leap year” with the other three representing one of the years leading up to it. For the first time, you could visually anticipate the occurrence of the leap year. Patek would later use this exact format to display the leap-year indicator in the subdial at three o’clock in both the 3940 and the 3970.

Unique ref. 3448 with leap year in place of moon phase
Unique ref. 3448 with leap year in place of moon phase

The story goes that Patek had their master watchmaker Max Berney rework the movement so that this modification could be made. A unique dial was fabricated by Stern Frères. In 2008, this watch emerged at an auction at Christie’s. It was sold for SFr.1,840,900 and has not been seen since. Undoubtedly, whoever owns this watch is aware he or she is in possession of a truly unique and historically significant treasure.

There was, at one point, a controversial variant of the 3448 that emerged on the auction scene in the early 2000s. I use the word “controversial” as there was much doubt over their legitimacy — a story well chronicled by Cara Barrett of Hodinkee. And the general consensus was that these were prototype or experimental dials created by Stern Frères, but never intended to be fitted to production 3448 watches. One key detail supporting this is that in the watches that did emerge at auction, all of them still had the corrector for the moon phase even though the dial didn’t display it, which is totally out of character with Patek’s traditional sense of perfectionism.

Ref. 3450

Successor to the 3448, made from 1981–85 with a total of 244 examples. Featured leap-year indicator and was powered by the calibre 27-460 QB, an updated version of the base calibre that was launched in 1962

Ref. 3450
Ref. 3450

Launched in 1981, the 3450 was made for a total of five years in just 244 examples. In many ways, the 3450 was identical to the fourth-series 3448 watches, with one critical difference. Tucked between the three and four o’clock indexes is a round aperture. Inside of this is an indication of where in the leap-year cycle you are. Earlier watches used Arabic numbers from “1” to “3” and later watches used Roman numbers to designate where in the three-year run-up to the leap year you are. In the leap year, the aperture turns unmistakably red. The 3450 marks the return of the centrally mounted seconds hand, something not seen on a Patek perpetual calendar since the 2497/2438-1. The movement powering this reference is the calibre 27-460 QB. Of the 244 examples, it is believed that only two examples were made with white gold cases, with the rest in yellow gold. A nice yellow-gold version will cost between US$200,000–300,00 while a white-gold version sold at Phillips in 2015 for US$1.5 million.

The ’80s to the ’90s — The Era of the Most Undervalued Vintage Perpetuaal Calendars

Ref. 3940

Launched in 1985 (post-Quartz Crisis) together with the ref. 3970. The first perpetual calendar watch with leap-year and 24-hour indicators in subdials. 36mm in diameter and powered by Patek’s micro-rotor calibre 240. Patek owner Philippe Stern’s daily watch

Ref. 3940
Ref. 3940

The year was 1985 and the Swiss watch industry had been decimated by the Quartz Crisis. Two-thirds of the industry’s workforce had left or been retrenched. But in the early to mid-’80s, a few visionaries were staging the comeback for complicated mechanical watchmaking, chief amongst them Philippe Stern, president and owner of Patek Philippe. He was still four years away from unveiling the calibre 89 in celebration of Patek’s 150th anniversary, the world’s most complicated timepiece and a symbol of the renaissance for haute horlogerie. But you can imagine that he checked in every day with a team headed by Jean-Pierre Musy. So it is remarkable that in the context of 1985, Philippe Stern, like his grandfather Charles Stern did in 1941, unveiled not one but two of the most iconic timepieces in watchmaking history.

Both the 3970 and the 3940 are perpetual calendars using the same in-house-designed module which places a leap year indicator in the subdial at three o’clock, and a 24-hour time indicator at nine o’clock — important as the module should not be adjusted near the midnight threshold when the calendar information is changing over. While the 3970 united this module with the venerable Lemania 2310 chronograph calibre, the 3940 marries it with possibly the most beautiful micro-rotor equipped automatic movement ever designed, Patek’s extra-thin calibre 240.

Cal. 240
Cal. 240

The 3940 is, in my opinion, one of the most perfect watches ever created. Amusingly, it is the first perpetual calendar since Patek introduced the complication in 1925 that provides all information using a series of subdials. Day is told from a ring surrounding the 24-hour indicator at nine o’clock while month is printed on a ring around the leap-year indicator at three o’clock. The date is read off a ring that surrounds the moon phase indicator at six o’clock. The dial uses a combination of stick markers with sharp points, a round applied dot minute track and dauphine-style hands. The case measures 36mm in diameter, and features a sapphire caseback from which you can observe the sublime movement within. The profile of the watch is extremely refined and elegant, thanks to the use of a shallow concave bezel. Today, the 3940, which enjoyed a long production run from 1985 to 2006, is considered a relatively common watch and as such, prices hover around the US$30,000 mark, making it the ideal first complicated Patek Philippe for a burgeoning collector.

The 1990s and the Return of the Retrograde Perpetual Caledar

Ref. 5040

Launched in 1992. Patek’s first tonneau-shaped perpetual calendar, and also the first to use Breguet numerals

Ref. 5040
Ref. 5040

In 1992, Patek Philippe introduced their first tonneau-shaped perpetual calendar — a masterpiece of Art Deco-infused style known as the 5040. To me, this is one of the most elegant complicated watches in existence. In many ways, it is the ultimate dandy’s complicated timepiece; something that should be found in the collection of a man that owns a Cartier Tank Cintrée. And yet somehow, possibly because in general men have not connected with tonneau-shaped timepieces, this is one of the most overlooked references in Patek Philippe’s history, with prices between US$30,000 to US$40,000. The dial of the watch is stunning. The 5040 is the very first serially produced Patek perpetual calendar to feature Breguet numerals as indexes. These are complemented of course by — what else — Breguet-style hands and a refined chemin de fer minute track. The layout of information is identical to the 3940, as is the movement powering this ravishing 35mm-diameter (42mm lug to lug) timepiece. It is conceivable that the watch’s modest size is slightly out of touch with contemporary tastes, but as men retreat to more classic proportions, I feel it is just a matter of time before they rediscover the beauty of the 5040. In addition, the watch is driven by Patek’s gorgeous micro-rotor-equipped calibre 240 Q.

Ref. 5050

Made from 1993 to 2002. The first perpetual calendar with retrograde date based on the Patek pièce unique ref. 96 from 1937

Ref. 5050
Ref. 5050

In 1993, Patek injected a brilliant sense of dial-side animation to their perpetual calendar in the form of a retrograde date indicator. As you know by now, this was not the first instance where the firm had created this type of complication. The first instance of a retrograde perpetual calendar dates all the way back to 1936/7, in a unique watch using a modified Victorin Piguet ébauche. This was also the very first time twin apertures were used to display day and month on a wristwatch. However, the reference 5050 marked the very first time this complication was serially produced. The 5050’s date display arced over the top half of the dial and was read off a centrally mounted hand. Day and month were displayed in two apertures placed at the outer perimeter of the dial at nine and three o’clock respectively. Moon phase was displayed at six o’clock. Overall, the reference 5050 in its 35mm Calatrava case is a slim, moderately sized and very elegant watch. Unlike many of the perpetual calendars in Patek’s line-up, it does not use the micro-rotor-equipped calibre 240, but a full-rotor calibre 315 S QR, which can be viewed through the model’s display back. Over the course of its lifespan, a great many dial varieties were created for the 5050, some using simple baton indexes, some using Roman numerals, and my personal favourites, which feature applied Arabic indexes. The 5050 features a centrally mounted seconds hand. Of these, I find the yellow-gold model with black lacquer dial to be the most stunning in the flesh. Today, these watches represent a strong value proposition with prices hovering around the US$50,000 mark.

Ref. 5050 in yellow gold case with black dial and applied Arabic numerals
Ref. 5050 in yellow gold case with black dial and applied Arabic numerals
Ref. 5041

Introduced in 1995, Patek’s second serially produced tonneau-shaped perpetual calendar. Made in no more than 30–50 examples

Ref. 5041
Ref. 5041

The reference 5041 is one of the most interesting modern Patek Philippe perpetual calendars around. As early as 2007, at a Christie’s auction, one of these watches was already hitting the price of SFr.181,000. Why? The reason boils down to two things. First is the unique good looks of the watch. This is the second tonneau-shaped Patek Philippe perpetual calendar ever serially produced. And at 35mm by 43mm, it is at the same time decent-sized enough on the wrist to suit modern tastes. All 5041 watches come in a stunning combination of white gold case, lush black lacquered dial and white-gold applied Breguet numerals with applied dot minute track. Inside the watch is the slim micro-rotor-equipped calibre 240, allowing for a 9mm height for the timepiece. The second and perhaps more compelling reason was the watch’s rarity. It is believed that no more than 30–50 examples of this watch were ever made. Today, the prices of the 5041 have come down significantly to the US$60,000 range, which to my mind, makes them one of the most undervalued complicated Patek Philippes out there.

Ref. 5059

A more robust-style Patek perpetual calendar, featuring an officer’s caseback

Ref. 5059
Ref. 5059

In 1999, Patek Philippe took the same retrograde perpetual calendar movement, the calibre 315 S QR, and housed it in a 36mm, decidedly thicker, more robust and aggressively-styled officer’s caseback to create the reference 5059. Whether or not you respond to this model is something of a matter of personal taste. I happen to like it, especially the hunter caseback that is hinged so that you can flip it up to display the movement that is protected underneath. The particularity of the 5059 has to do with its very long straight lugs, where the strap is affixed using a large visible screw head, giving the timepiece a dash of vintage military-style panache. The dial features a plethora of information with Roman indexes, a chemin de fer for the minutes and a full seconds track, which can be read off the watch’s large centrally mounted hand. Prices for the 5059 are slightly soft at the moment and pre-owned watches are trading between US$30,000–50,000.

So, here ends this historical journey of Patek Philippe with the perpetual calendar just before the turn of the new millennium.