By 1974 the Royal Oak launched two years earlier had become a slow-burn commercial success and an early reference for what would become the luxury steel sports watch category. Patek Philippe, the most conservative of the major Swiss houses, was watching the new category form and considering an entry. Patek had built its identity on gold dress watches (Calatrava, Golden Ellipse, complicated pocket watches); a steel sports watch ran against that identity. Philippe Stern, then in his early thirties as Henri Stern's son and the eventual head of the firm, championed the project against family scepticism.
According to Gérald Genta's own account, the design originated at lunch at the Hotel Beau-Rivage in Geneva during the 1974 Basel Fair. Genta noticed Patek Philippe executives at a nearby table; over the next five minutes he sketched a watch on the placemat based on a marine porthole he had been thinking about for some time. The case form was an oval rather than an octagon (Royal Oak), with two prominent hinged-looking "ears" on the case sides at 9 and 3 o'clock, references to the rotating-and-locking mechanism of a real ship's porthole. Genta sent the sketch to Patek the next week.
"One of the world's costliest watches is made of steel."- Patek Philippe original Nautilus 1976 launch advertising slogan
The watch that emerged through development was the reference 3700/1A, presented at the 1976 Basel Fair. Specifications: 42 mm steel case (the "Jumbo", 4 mm larger than the era's standard wristwatch and 3 mm larger than the Royal Oak 5402), integrated steel bracelet, horizontally embossed blue/grey dial, "PATEK PHILIPPE GENEVE" applied wordmark, and the JLC Cal. 920 automatic ultra-thin movement (the same base as the Royal Oak's Cal. 2121, though Patek-modified). The launch price was CHF 3,100; the marketing campaign featured the slogan "One of the world's costliest watches is made of steel".
The 1976 reception was lukewarm. Patek's traditional client base (older European families, established Swiss collectors) saw the steel sports concept as inappropriate for the maison; the new luxury sports market was still small. Annual production ran roughly 1,000-1,200 pieces through the 1980s, often sitting in dealer cases for months. The reference 3700 was discontinued in 1990 and replaced by the smaller (37 mm) 3711. By 1990s standards the original 3700 was viewed by collectors as an obscure curiosity; second-hand prices were low through the late 1990s.
The 21st-century reversal was dramatic. The 5711/1A launched in 2006 as the modern flagship: 40 mm steel case, blue dial with the original 1976 horizontal embossing, in-house Cal. 324 automatic. Sales were brisk; by the mid-2010s Patek demand had outstripped allocation; by 2018-2020 the 5711 had become the central object of the modern allocation-driven luxury watch market, with retail prices of CHF 30,000 and grey-market prices peaking near CHF 200,000 in April 2022. Thierry Stern (Philippe's son, current Patek president) discontinued the steel 5711 in 2021 in an attempt to reset the speculation pressure; the announcement created an immediate price surge as collectors raced to secure the last allocations.
The Nautilus today consists of the 5711 (discontinued 2021), the 5712 power reserve / moonphase, the 5980 chronograph, the 5990 travel-time chronograph, and the 5740 perpetual calendar; the modern flagship steel three-hander is the 5811/1G in white gold (replacement for the discontinued steel 5711, launched 2022). Vintage 3700 examples in original condition trade at CHF 80,000-CHF 250,000+; the original Tiffany & Co.-stamped 5711 last edition (170-piece run for the 175th anniversary of Tiffany, 2021) holds the highest auction price of any modern steel watch at USD 6.5 million (Phillips New York, December 2021).