British watch retailer chain Watches of Switzerland Group is contemplating a listing on the London Stock Exchange to further grow in its home market as well as across the pond, according to Bloomberg.

Now owned by American private equity outfit Apollo Global Management, the group is the largest in the United Kingdom, with 2018 revenue of £773m, which is just over US$1 billion. The group owns over 130 stores in the UK that bear familiar high street names, including Mappin & Webb and Watches of Switzerland.

About half its sales comes from Rolex watches, making Watches of Switzerland the biggest retailer of Rolex in the United Kingdom. In fact, the group is also the biggest retailer for Patek Philippe, Cartier, and Omega.

Having grown sales at an average of 18% a year since 2014, the group started its North American expansion in 2017, when it bought the Mayors, which has stores in Florida and Georgia. And earlier this year Watches of Switzerland opened its newest American store inside New York’s Hudson Yards shopping complex, joining its store inside the Wynn Las Vegas.

Watches of Switzerland isn’t the only European retail giant expanding in the United States, where a fragmented market and ageing stores mean many retailers are struggling. The continent’s biggest watch retailer, Switzerland’s Bucherer, acquired two American retail chains, Tourneau as well as Baron & Leeds, in 2018. It has kept both brand names, while investing heavily in stores and marketing to grow its presence.

A listing would see about 25% of the group’s shares publicly traded, with Apollo retaining its majority stake. The group would be valued at up to £1 billion (US$1.3 billion) in a listing, according to a source quoted by Reuters.

One of the most intriguing watches that will be offered in the upcoming Geneva watch auction season is the prototype Patek Philippe Aquanaut ref. 5060 that’ll go under the hammer at Antiquorum.

Labelled “prototype” on the dial, and “labo” (short for laboratoire) on the movement, the watch is equipped with a “comet” power reserve, a complication that was never found on the production Aquanaut.

The “comet” power reserve located at 11 o’clock is familiar as the signature feature of the Nautilus ref. 3710/1A. Named after the motion of the indicator, the power reserve hand moves from the narrow to the wide portion of the power reserve scale as the watch is wound up, but once it is fully wound, the entire power reserve sub-dial rotates if winding continues. That’s because the sub-dial is linked to the slipping barrel that sits underneath, so when the watch is wound with a full mainspring the barrel rotates without tightening the mainspring any further.

The dial is a smooth black, with hands and hour markers identical to that of the Nautilus

But the unnecessary complexity of the idea meant it was overly difficult to explain and understand, which is presumably why Patek Philippe abandoned the feature after the ref. 3710/1A was discontinued in 2005.

Featuring a date function and a chequerboard dial, the production Aquanaut ref. 5060A was launched in 1997 as the more casual and affordable cousin of the Nautilus. This prototype, on the other hand, has the same calibre 330 as the Nautilus ref. 3710/1A, which was introduced a year later. So it stands to reason this prototype was made to test a concept that was discarded in favour of the Nautilus.

The movement is engraved “LABO No 04”

This is a proper prototype watch – the Oxford English Dictionary defines prototype as “a first or preliminary version of a device or vehicle from which other forms are developed” – rather than the pseudo-prototypes, identical to the stock models and numbered “0” or “00”, which are often sold by watch brands themselves for special occasions or charity.

Prototype watches are almost always sold at Geneva auctions because they are usually owned by former watchmakers or employees of watch brands. One recently sold but vintage example was the Omega tourbillon wristwatch that sold at Phillips two years ago for US$1.4m. And another was a modern day Jaeger-LeCoultre Reverso with a prototype dial that sold for US$40,000, or about eight times what the stock model would go for.

But only a tiny number of prototype Patek Philippe watches of any vintage have appeared in public; examples include the ref. 3412 designed by Gilbert Albert and a Nautilus ref. 3700 “Jumbo” with a white dial.

Antiquorum states that because this watch is a prototype, there is no extract from archives available.

The Aquanaut prototype has an estimate of 50,000-80,000 Swiss francs, and is lot 726 in Antiquorum’s Geneva watch auction that place on May 11 and 12, 2019. For more information, visit Antiquorum.swiss.