Patek Philippe’s “Asprey” Ref. 2499 perpetual chronograph is to Patek Philippe collectors what Paul Newman’s “Paul Newman” Daytona Cosmograph Ref. 6239 is for Rolex enthusiasts: one of the most historically important and enormously rare wristwatches in the world. Sold at Sotheby’s November 13 auction for $3,915,000, the yellow gold Ref. 2499, one of two perpetual calendar chronographs, is the most complicated of the pair, double signed on the dial by Asprey and Patek Philippe, and the most expensive timepiece of the year. But first, a little back story.

Known as the “ultimate Patek,” Ref. 2499 was manufactured between 1950 and 1985. Nearly 350 wristwatches were made during that time, averaging nine a year. Although large for its day, “The Asprey”, with its 37.6mm diameter case, was manufactured in 1952 and sold in 1956. It is one of the first series pieces manufactured and, as far as we know, was the only piece with the Asprey signature. What’s more, there are no more than 40 pieces made in yellow gold.

“The Asprey” Twenty-Four Ninety Nine is a legend in the world of collecting. According to the story, it was sold by its owner in 1990 and later bought by a collector who then consigned it to Sotheby’s. Last seen in 2006, it sold for CHF 2.2. million, making it the most expensive first series in gold at the time. It has been in the same private collection since 2006. But here’s the kicker, though: a first series Serpico y Laino-signed 2499 went under the hammer and sold for CHF 3,252,500 ($ 3.23 million) on November 12, just one day before the historic auction. And Christie’s sold a third series, bearing no additional signature, for CHF 672,500 ($668,500) that very same day.

“This is the only known 2499 to be retailed by Asprey and is the most complicated Patel Philippe wristwatch to be sold by Asprey, “ said Sam Hines, Global Head of Sotheby’s Watch Division. “The watch,” he continues, “was sold to David Duggan watches in London by the original owner in 2005. The hands are also very interesting as they are luminous, which is also very rare feature in itself. Following on from the record sale last week of the pink gold 2499 Tiffany in Hong Kong, there is a huge appetite for watches of this caliber and we are very much looking forward to the sale of these extraordinary collectors’ watch.”

While the identity of the buyer’s was not immediately known, the successful bidder was described as a young Asian woman in torn jeans in the back row of the sale room who spoke Chinese. There is, however, a larger point: a few timepieces bandied about here or there gives no one pause. But much like the excitement and enthusiasm behind, let’s say, Paul Newman’s “Paul Newman” Daytona Cosmograph Ref. 6239, indicates that “The Asprey’—aside from being this year’s the most expensive lot of Geneva sales—demonstrates genuine interest from collectors. And with more than two dozen yellow gold pieces out there, there is a definitive market for 2499s and collectors are willing to pay. How much is anybody’s guess. One thing is for sure: it gives new meaning to the phrase, “You never actually own a Patek Philipp.”