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The Genta-designed original Nautilus; the porthole case language it introduced is still in production fifty years later.

Rare · ~3,000-3,500landmark#2 in familyOfficial press photos

Originality

Originality matters on this reference. An original dial and hands command a significant premium. Service replacements typically trade at a 20-40% discount to original examples.

Condition affects price

Pre-owned watches trade across a wide condition spectrum. These ranges are typical for the secondary market.

New Old Stock
Unworn example retaining original packaging, tags, and warranty documentation.
+30–50% vs median
Unpolished
Worn but the case has never been polished; original brushed and polished surfaces are intact.
+15–25% vs median
Polished
Case has been professionally or amateur polished at some point; edge definition is softened.
-15 to -5% vs median
Recently Serviced
Movement has been recently serviced with documented service records; case condition varies.
At median
Project
Needs service, has dial or hand issues, non-original parts, or other remediation before daily wear.
-50 to -25% vs median

Full condition grading guide →

Market price

$80,000$150,000
steel·2026 Q2
Price trend chart coming soon

The first-generation 3700 Nautilus is a significant vintage collector piece; original steel examples in unpolished condition with correct dials command auction-level prices, and recent Phillips results have pushed strong examples well above $100,000.

Editorial estimate, 2026 Q2. Actual prices vary by condition, date, and box/papers status.

Movement tier: unclassified · caliber Patek Cal. 28-255 C: ultra-thin automatic with date, 19,800bph, 40h PR, 29j; 3.05mm thick; integrated winding; used in 3700 Nautilus · 40h power reserve · family design Gérald Genta
Medium-large: suits wrists 6.5 in+ (16.5 cm+)
42 mm case. Wears confidently on average to larger wrists. May overhang on slender builds.

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Authentication

The original 3700 Nautilus is a vintage reference with distinct authentication challenges from the modern 5711. Movement and dial aging consistency are primary concerns.

Known issues in the market
  • Dials have been refinished to restore faded Nautilus embossing; original aged dials are preferred by collectors.
  • The integrated bracelet has been replaced or modified on many surviving examples.
  • Cal. 28-255 C movements have been serviced extensively and some have non-original parts.
AreaWhat to checkWhat is correctRed flag
dialHorizontal stripe pattern agingOriginal 3700 dials show natural aging with subtle color shift toward warm brown-blue; embossing depth is consistentUniform blue with no aging on a stated 1970s-1980s dial; artificially enhanced or repainted dial pattern
movementCal. 28-255 C identificationJaeger-LeCoultre base movement, modified by Patek; extra-thin automatic with Patek finishing standardNon-JLC-base architecture in the 3700; movement serial inconsistent with case generation
Common legitimate replacements
  • Bracelet links and clasp are commonly replaced on vintage Nautilus; original bracelets command a premium.
  • Crown replacement is documented; confirm period-correct profile.
Expert resources: Phillips Geneva auction archives contain authenticated 3700 examples with cataloged condition notes. The Patek collectors forum at WatchUSeek has vintage Nautilus authentication discussions. Extract of the Archives from Patek confirms factory specification.

Authentication guide

Last reviewed June 2026

The original Nautilus 3700 is the most significant Genta-designed sport watch of the 1970s. Dial aging consistency, Cal. 28-255 C movement integrity, and bracelet originality are the primary authentication pillars.

Known reproduction risks

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HIGH RISK

Complete replicas of the 3700 are less common than 5711 fakes but exist at mid-price points.

  • Horizontal embossing that appears flat or printed under directional lighting -- genuine 3700 embossing casts a shadow and is tactile
  • Applied "Patek Philippe" text that is flat or printed rather than three-dimensional
  • Octagonal bezel that does not integrate correctly with the round case flanks -- the Genta bezel-to-case transition is a precise geometry
  • Exhibition caseback showing a non-JLC-architecture movement
MEDIUM

Authentic-case examples with non-original or partially replaced movement components.

  • Movement without Geneva seal striping on the bridges -- indicates non-Patek service finishing
  • Non-original bracelet with different link dimensions or finishing direction from the authentic 3700 specification

Dial variants by era

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EraDescriptionIdentifiers
1976 to 1983 (early 3700)Blue-grey embossed horizontal stripe dial. Slightly warmer blue tone than later production.
  • Blue-grey horizontal embossed stripe texture -- the embossing is tactile and three-dimensional
  • "Patek Philippe" applied text (raised, not printed) with Calatrava cross above 12
  • Baton indices with lume filling; tritium lume ages to cream-to-tan on examples from this era
  • No date window on the ref. 3700/1 (time-only); date present on the 3700/1A
1983 to 1990 (later 3700)Slightly revised dial proportions in later production. Same horizontal embossed pattern.
  • Horizontal stripe embossing consistent with early production but sometimes slightly more saturated blue
  • Tritium lume plots show visible aging consistent with 1980s production
  • Applied "Patek Philippe" text with the same three-dimensional Calatrava cross

Service part flags

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Dial

Original: Original 3700 dials show natural aging over 40-plus years: subtle color shift toward warm brown-blue, lume patina matching the production era, and no signs of mechanical refinishing. The embossing depth should be consistent from edge to edge.

Replacement tells
  • Uniform vivid blue with no aging on a stated 1970s-1980s dial -- Patek dials from this era show subtle tonal shift toward warm brown-blue
  • Embossing that fades or becomes less defined toward the dial edges -- indicates dial refinishing that did not fully restore the texture
  • Applied "Patek Philippe" text that shows any loss of three-dimensional quality or flat-printing characteristics
  • Lume plot color inconsistent with the dial aging tone
Integrated bracelet

Original: Original 3700 bracelet uses the folded-center-link design specific to the Nautilus. The bracelet tapers toward the PP clasp. On a 40-plus-year-old watch, the bracelet may show wear consistent with the case; an overly pristine bracelet on an aged case is a flag.

Replacement tells
  • Bracelet that does not taper correctly toward the clasp -- correct taper is a defining Nautilus design element
  • Center links with incorrect brushing direction or polishing that does not match the case finishing
  • Non-PP clasp markings or clasp with typography inconsistent with known Patek 1970s-1980s production
  • Replacement bracelet from a later Nautilus generation with different link dimensions
Crown

Original: Period-correct crown at 9 o'clock position with Patek coin-edge profile. Winding is smooth with correct resistance for an ultra-thin movement.

Replacement tells
  • Crown at 3 o'clock -- wrong position for all Nautilus references
  • Crown profile that does not match known Patek 3700-era crown geometry
  • Rough winding engagement suggesting the crown tube or stem has been damaged and replaced with a non-original part

Case back markings

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1976 to 1990
  • Exhibition caseback (display window) -- the 3700 has a display caseback showing Cal. 28-255 C
  • "Patek Philippe Geneve" engraved on the caseback in correct Patek typeface
  • Reference 3700/1A (or 3700/1 for no-date) engraved on the case band
  • Serial number on the case band at 9 o'clock position
  • Swiss hallmarks for the stated case material (steel) stamped on the case band

Movement tells

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  • Cal. 28-255 C is a Jaeger-LeCoultre base movement (JLC Cal. 920) modified by Patek to their finishing standard. The movement is ultra-thin at 2.45mm.
  • No quickset date -- the date (on the 3700/1A variant) corrects only by rotating the crown through the hours.
  • JLC-base architecture: the movement uses a specific bridge layout characteristic of the JLC 920 family. A watchmaker familiar with JLC movements can confirm the base architecture.
  • Patek finishing standard: all exposed bridges should have Geneva seal striping (Cotes de Geneve), polished chamfers, and blued screws. Any deviation from this standard suggests either non-Patek service parts or a non-Patek movement.
  • An authentic service record from Patek Philippe or a Patek-authorized watchmaker is the strongest provenance document available for the 3700.
Sources: Phillips Geneva -- authenticated 3700 auction archives; WatchUSeek Patek Philippe forum -- vintage Nautilus 3700 authentication discussions; Patek Philippe Extract of the Archives -- confirms factory specification by serial.

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