Patek Philippe Ref. 3970

A complication few wanted to buy

Patek Philippe made the world's first serially produced perpetual calendar chronograph wristwatch, the ref. 1518, in 1941, and only 281 were made. Its successor, the ref. 2499, followed in 1951, and just 349 were made over its long run. Both are now among the most expensive wristwatches in the world. The ref. 3970 is the watch that took over from them, introduced in 1986, one year after its sister perpetual calendar, the ref. 3940.

The timing was strange. Quartz watches had upended the industry, and, as one former auction specialist put it, people in the 1980s did not care about complicated watches, or even chronographs. John Reardon, a longtime Patek Philippe specialist who later wrote books on the brand, has said that retailers did not even want to take the 3970 from Patek because it was too hard to sell. He remembered the 3970 and the split-seconds ref. 5004 as watches that were 'not easy to sell' in the early 2000s.

They were also expensive. By 2000 a gold 3970 retailed for about $77,000 and a platinum 3970P for about $90,000, which made it one of the costliest regular-production watches of its time. These were watches a retailer could simply order for a client, long before the era of waiting lists and allocations.

Over time the 3970 and the 3940 became the core of a revival of traditional, complicated watchmaking at Patek Philippe. The brand's 150th anniversary in 1989, marked by the Caliber 89, then the most complicated watch in the world, gave that revival a stage, and the 3970 was the most important complicated wristwatch in the regular catalog.

A Lemania engine, finished in Geneva

The 3970 was the first Patek Philippe chronograph built on something other than a Valjoux movement. Its caliber CH 27-70 Q starts from the Lemania 2310, a manual-wind, column-wheel chronograph first introduced in 1942 and credited to designer Albert-Gustave Piguet. The same family of movements gave Omega its caliber 321, the movement of the early Speedmaster, and was also used by Vacheron Constantin, Breguet and others.

The 2310 is compact, about 27 mm across and 6.74 mm thick, which is what allowed Patek Philippe to keep the 3970 small. Patek started from the updated 2320 version, with 21 jewels, and took it apart: the swan-neck regulator was removed, a polished cap was added to the column wheel, and with the perpetual calendar module on top the jewel count rose to 24. Assembly, adjustment and finishing were done in-house. The movement runs at 18,000 beats per hour and has a 60-hour power reserve, and by one account it was the first chronograph movement to carry the Geneva Seal.

One watch writer judged Patek's version the most elaborate of all the brands that used this Lemania base, and noted that even Vacheron Constantin did not have a comparable perpetual calendar chronograph until 2000. The same caliber went on to power the cushion-shaped ref. 5020 from 1994 and the 3970's successor, the ref. 5970.

The cases came from Ateliers Réunis, the casemaker Patek Philippe had acquired, which stamped its key number 28. Specialists believe that master case maker Jean-Pierre Hagmann made some cases for early 3970s, a possibility collectors check by looking for his hallmark.

Four series, told apart by backs, hands and fonts

The dial follows the family layout: day and month in two windows below 12, the date with moon phase at 6, a 30-minute chronograph register with a leap-year indicator at 3, and running seconds with a 24-hour indicator at 9. The calendar disks were made in Italian, English, German and French, which is why experienced buyers check that 'MAR' means March and not Marzo. The series were defined later by collectors, not by Patek Philippe, and the changes were gradual, since parts were made in batches and used as they came to hand.

The first series, made in 1986, numbers about 100 watches, all in yellow gold. It has a snap-on solid case back with no real water resistance, leaf-shaped (feuille) hands, baton markers and sub-dials noticeably darker than the rest of the dial, a two-tone look that sets it apart. A sister reference, the 3971, launched alongside it with a sapphire snap-on back; one account puts total 3971 production below 300.

The second series introduced a solid screw-down back, and with it the 3970E name, and opened the line to yellow, rose and white gold and platinum. Sources date it differently, 1987 to 1990 in one account and 1986 to 1991 in others. About 650 were made, a figure that includes 150 to 200 ref. 3971s. White gold is very rare here: one account says 14 are known, another says six.

The third series, from 1989 to about 1995, roughly doubled the annual output, with about 1,350 made. Every watch now came with both a solid and a sapphire screw-down back, and the dial changed to baton hands, pointed faceted markers and a brighter silver surface. The fourth series, from about 1994 to 2004, numbers about 2,000 and differs mainly in its case and movement number ranges and a folding clasp in place of the pin buckle.

Sources disagree on the total. One collector's guide says about 4,000, another 'over 3,000,' and a third estimates 2,400 to 3,600. They also disagree on the case height, given as 13 mm in one guide and 13.5 mm in another. All agree the case is 36 mm across.

From below retail to six figures

For years the 3970 was the overlooked member of its family. By the time the 5970 arrived it looked small, and in 2004 standard 3970s often sold at auction below their retail price, roughly $60,000 to $70,000, with almost no difference between a first series ($76,200) and a fourth series ($64,400). As late as 2014 an auction specialist struggled to find bidders for a yellow gold 3970E estimated at $60,000 to $80,000, and in 2018 a leading watch magazine asked why no one seemed to care about the reference.

Special dials were the exception. In November 2013 a special-dial 3970 sold in Hong Kong for $339,552, then the highest price for the reference. In late November 2016 Eric Clapton's white gold 3970, with a salmon dial, Breguet numeral at 12 and tachymeter scale, sold in Hong Kong for HK$3,560,000, or $459,000, about $50,000 more than his split-seconds ref. 5004 brought in the same sale. His rose gold 3970 brought roughly $200,000 less than the white gold one.

The highest public price for any 3970 is $785,000 (HK$6,104,000), paid in Hong Kong in October 2021 when that same possibly unique white gold watch, made in 2008, returned to auction; its catalog noted it had first been offered five years earlier. Similar special-order yellow and rose gold examples have passed $600,000.

Then the first series took off. In 2024 several first-series watches reset the market: one with movement number 875004 sold for $416,000 in Hong Kong in November; one numbered 875015 brought $305,000 in Geneva the same month; and in December, in New York, $312,000 was paid for the second 3970 ever produced, movement number 875001, owned and worn by Tom Brady. Later-series yellow gold 3970s in the same November sales brought $120,000 to $170,000. A first series sold in Basel in March 2024 is reported at $281,000 in one list and $218,000 in a photo caption from the same guide, so that figure is left out of the price history.

As of February 2025 about 16 first-series watches had appeared on the market, fewer than a quarter of those made.

Clapton, Ovitz and the London edition

Patek Philippe made special 3970s for important clients during and after regular production. Eric Clapton's commissions typically added Breguet numerals, chronograph scales and unusual dial colors. Michael Ovitz, the Hollywood agent and former Disney president, later commissioned several, identifiable by his logo at 6 o'clock. After production ended in 2004, special orders continued, often with a Breguet 12, a tachymeter scale and combinations such as black dials in rose gold or platinum and salmon in white gold. Sets of four 3970s, one in each metal with full Breguet numerals, are believed to have been made for top clients around the end of production.

In 2015, for the Watch Art Grand Exhibition in London marking its 175th anniversary, Patek Philippe released a selection of previously discontinued pieces with special dials, among them a 3970 in rose gold (3970ER-028) and platinum (3970EP-046) with a black dial, Breguet numeral at 12, applied dot markers and tachymeter. One guide says about five were made; an auction catalog calls the platinum one it sold 'one of three known.' That watch had stayed in its factory seal until January 17, 2023, when it was opened for shipping, and it sold in Geneva later that year for CHF 571,500, about $636,000.

Rare variants also existed inside regular production: black dials on platinum, usually with diamond markers; a few original doré (champagne) dials in yellow gold; dials co-signed by Tiffany & Co.; and the 3970/2 on an integrated gold bracelet, of which as few as 10 are reported in yellow gold. A fourth-series 3970EP-019 fitted with a special replacement dial around 1997 sold for $352,800 at auction in 2023.

The numbers

Reference

3970 (3970E from the second series); 3970/2 on bracelet; sister ref. 3971 with sapphire back (1986 to the second series)

Caliber

CH 27-70 Q, manual wind, Lemania 2310/2320 base, 24 jewels, 18,000 beats per hour, about 60 hours of power reserve

Case

36 mm; height given as 13 mm or 13.5 mm by different sources; 18K yellow, rose and white gold, and platinum

Production years

1986 to 2004

Production by series (estimates)

First about 100 (1986); second about 650 including 150-200 ref. 3971; third about 1,350 (1989-1995); fourth about 2,000 (1994-2004)

Total production

Not published; estimates range from 2,400-3,600 to about 4,000

Retail

About $77,000 in gold and $90,000 in platinum in 2000

Timeline

1. 1941

   Patek Philippe introduces the ref. 1518, the first serially produced perpetual calendar chronograph wristwatch.

2. 1951

   The ref. 2499 succeeds the 1518; 349 are made over its run, which sources end between 1985 and 1987.

3. 1985

   The ref. 3940 perpetual calendar is introduced, one year before the 3970.

4. 1986

   The ref. 3970 and its sapphire-backed sister ref. 3971 are introduced; about 100 first-series 3970s are made in yellow gold with snap-on backs.

5. 1987

   The second series begins (1986 in some accounts), with a screw-down back (3970E) and all four case metals; about 650 are made with the 3971.

6. 1989

   Patek Philippe's 150th anniversary; the third series begins, with baton hands and pointed markers, about 1,350 made.

7. 1994

   The fourth series begins, adding a folding clasp; about 2,000 are made. The cushion-cased ref. 5020 uses the same caliber.

8. 2000

   A gold 3970 retails for about $77,000 and a platinum 3970P for about $90,000.

9. 2004

   Production ends; the 40 mm ref. 5970 succeeds it. Standard 3970s sell at auction for $60,000-70,000, below retail.

10. 2008

    A white gold 3970 with salmon dial and Breguet numeral is made for Eric Clapton.

11. Nov 2013

    A special-dial 3970 sells in Hong Kong for $339,552, a record for the reference at the time.

12. 2015

    Patek Philippe releases black-dial 3970s in rose gold and platinum for its 175th-anniversary exhibition in London.

13. Nov 2016

    Clapton's white gold 3970 sells in Hong Kong for $459,000, outpacing his ref. 5004 in the same sale.

14. 2018

    A leading watch magazine asks why no one seems to care about the 3970.

15. Oct 13, 2021

    Clapton's white gold, salmon-dial 3970 returns to auction in Hong Kong and sells for HK$6,104,000 (about $785,000), the highest public price for the reference.

16. Jan 17, 2023

    A sealed platinum London-exhibition 3970 is opened for shipping; it later sells in Geneva for CHF 571,500 (about $636,000).

17. Nov 2024

    A first-series 3970J, movement 875004, sells in Hong Kong for $416,000; another, 875015, brings $305,000 in Geneva.

18. Dec 2024

    The second 3970 ever made, movement 875001, owned by Tom Brady, sells in New York for $312,000.

19. 2026

    The reference marks its 40th anniversary.

The world in 1986

• Jan 28, 1986

  The Space Shuttle Challenger breaks apart 73 seconds after launch, killing its crew of seven.

• Feb 9, 1986

  Halley's Comet reaches perihelion on its second visit of the 20th century.

• Feb 17, 1986

  The Single European Act is signed.

• Feb 22, 1986

  The People Power Revolution begins in the Philippines against President Ferdinand Marcos.

• Apr 26, 1986

  The Chernobyl nuclear disaster strikes in the Soviet Union.

• Jul 5, 1986

  The Statue of Liberty reopens to the public after its centennial restoration.

• Oct 11, 1986

  Ronald Reagan and Mikhail Gorbachev meet in Reykjavík to discuss missile reductions.

Price record

A realized auction price is what a buyer actually paid on the date shown, including the buyer's premium where the sale reported it. It is the strongest kind of reference price, and it is a record of one sale of one object on one day, not a promise of what the next example will bring.

By reference price, Patek Philippe Ref. 3970 is number 21 of 100 in the watches entries of the FLOAT 100. 54 of those 100 rest on a realized sale; the rest carry an asking price or a guide value, and each page says which. Rank within the FLOAT 100 itself (33 here) is editorial: how much an object defines its field, not price alone.

Did you know

• The 3970 was the first Patek Philippe perpetual calendar chronograph made in series in white gold.
• Despite arriving in the free-spending 1980s, the 3970 was smaller than the 2499 it replaced: 36 mm against 37.5 mm.
• A 1990s Patek Philippe advertisement in Paris showed a woman diving into the sea to rescue not her drowning companion but his 3970.
• The 'E' in 3970E stands for étanche, French for waterproof, after the screw-down back introduced with the second series.
• In 2004 a first-series 3970 sold at auction for about the same as a fourth-series one; twenty years later the earliest watches bring two to three times as much.
• A platinum 3970 made for the 2015 London exhibition stayed in its factory seal until January 17, 2023.
• Collectors check the calendar disk language closely, because 'MAR' can mean the Italian Marzo as easily as March.