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Common#5 in familyOfficial press photos

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

$32,000$48,000
varies by metal·2026 Q2
Price trend chart coming soon

The 50th Anniversary Royal Oak Chronograph 26240 re-established the chronograph family with integrated pushers and an integrated bracelet redesign; secondary prices reflect strong demand from collectors who passed on the original allocation.

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

Movement tier: unclassified · caliber AP Cal. 4401: AP's first integrated in-house chronograph, 32 x 6.8mm, 28,800bph, 70h PR, 40j, 367 parts; column wheel, vertical clutch, flyback, free-sprung balance under a full bridge, 22k openworked rotor; replaced the Frederic Piguet-based cal. 2385 in the Royal Oak chronograph from 2021 · 70h power reserve (2.9 days) · family design Gérald Genta
Medium-large: suits wrists 6.5 in+ (16.5 cm+)
41 mm case. Wears confidently on average to larger wrists. May overhang on slender builds.

Not yet rated

Community + OSINT signals haven’t landed for this reference yet. We don’t publish a rating against zero signal: the number would mean nothing. Editorial body + caliber + market value still surface above; ratings appear once the signal corpus does.

Search pre-owned listings

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Authentication

50th anniversary casebacks have specific commemorative engravings; confirm the caseback text before purchase.

Known issues in the market
  • Non-anniversary Royal Oak Chronograph cases paired with anniversary-spec dials.
  • Cal. 4401 flyback function misrepresented on listings; confirm flyback is functional, not a standard chronograph reset.
AreaWhat to checkWhat is correctRed flag
caseback50th anniversary engravingCommemorative 50th anniversary text and Cal. 4401 designation engraved on caseback; consistent with 26240 documentationMissing commemorative text; generic Royal Oak Chronograph caseback without anniversary markings
caseFlyback pusher functionSingle pusher press resets and immediately restarts chronograph; instantaneous with no hesitationTwo-press reset sequence (standard chrono behavior); any hesitation in flyback reset
dialTapisserie pattern and applied indicesRoyal Oak Tapisserie consistent with 26240 color specification; applied AP baton indices with correct lume applicationTapisserie color inconsistent with reference specification; incorrect index profile or lume color
Common legitimate replacements
  • Cal. 4401 is AP's in-house flyback caliber; third-party movement replacements are immediately detectable via caseback inspection.
  • Integrated stainless bracelet is reference-specific; non-original bracelets carry a value penalty.
Expert resources: AP 50th anniversary Royal Oak documentation at audemarspiguet.com. WatchUSeek AP forum for 26240 variant identification.

Authentication guide

Last reviewed June 2026

The 26240ST is the 50th anniversary Royal Oak Chronograph with in-house Cal. 4401. The anniversary edition features a bracelet that incorporates Tapisserie texture on the center links, matching the dial. This detail is the fastest bracelet authentication signal and differentiates it from the standard Royal Oak Chronograph.

Known reproduction risks

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MEDIUM

The 26240ST 50th anniversary edition is less widely reproduced than the standard Royal Oak, but the price premium makes it an attractive reproduction target.

  • Bracelet with flat-brushed center links rather than the authentic Tapisserie-textured links
  • Silver "AP" crown at 6 o'clock presented as a yellow-logo anniversary example
  • Movement without peripheral rotor architecture visible through caseback
  • "Grande Tapisserie" dial texture with rounded or inconsistent squares

Dial variants by era

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EraDescriptionIdentifiers
2022 to present (steel, blue/yellow AP on dial)The 50th anniversary edition uses a blue "Grande Tapisserie" dial with a yellow AP logo at 6 o'clock rather than the standard silver-tone logo. The bracelet center links are also textured with the Tapisserie pattern.
  • Blue "Grande Tapisserie" dial with a yellow "AP" crown at 6 o'clock -- yellow logo is specific to the 50th anniversary edition; standard chronograph uses silver-tone
  • Integrated "Tapisserie" bracelet: center links carry a Tapisserie relief pattern matching the dial texture; this is unique to the anniversary edition
  • Integrated pushers at 10 and 2 o'clock for the chronograph
  • Sub-registers at 3 (30-minute counter), 6 (small seconds), 9 (12-hour counter)
  • Date at 6 o'clock integrated into the small seconds sub-register area

Service part flags

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Tapisserie bracelet center links

Original: The Tapisserie-patterned center links are a 50th anniversary exclusive. The raised texture on the links should match the "Grande Tapisserie" density and relief depth of the dial. The link surface is brushed with the Tapisserie pattern superimposed.

Replacement tells
  • Standard flat-brushed center links without the Tapisserie texture -- indicates either a standard bracelet substitution or a non-anniversary dial paired with an anniversary bracelet claim
  • Tapisserie texture on links with a different square density than the dial
  • Link-to-case junction with a gap or step inconsistent with the original integrated architecture
Yellow AP crown at 6 o'clock

Original: Applied "AP" crown logo in yellow tone at 6 o'clock. The yellow tone is distinct and consistent under neutral light. The logo is raised above the dial surface.

Replacement tells
  • Silver-tone "AP" crown presented as the anniversary edition -- the standard Royal Oak Chronograph uses silver; yellow is the 50th anniversary specific element
  • Yellow applied logo that has any paint or coating inconsistency under 10x magnification
  • "AP" crown that is printed flush with the dial rather than applied above the surface

Case back markings

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2022 to present
  • Exhibition caseback displaying Cal. 4401 integrated chronograph
  • "Audemars Piguet" and "Le Brassus" on the movement
  • Peripheral rotor around the movement edge; engraved with AP pattern
  • Reference number "26240ST.OO.1320ST.04" on the caseback rim
  • Cal. 4401 uses a vertical clutch; the column wheel is visible through the caseback

Movement tells

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  • Cal. 4401 is identical in architecture to the Code 11.59 chronograph caliber; the same inspection criteria apply: peripheral rotor, vertical clutch, column wheel.
  • Zero displacement of the central chronograph seconds hand at start is the functional benchmark for the vertical clutch.
  • Power reserve is 70 hours from full wind; a significantly shorter reserve indicates mainspring wear.
Sources: Audemars Piguet — Royal Oak Chronograph 26240; Hodinkee — 26240 50th anniversary coverage, 2022.

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Buying guidance

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