The Patek Philippe Calatrava Reference 3565/1 "IOS Edition" is a historically significant luxury vintage timepiece commissioned in the late 1960s. This highly collectible model represents the largest corporate watch order in the history of Patek Philippe.

• The Commission: The watch was ordered by Bernie Cornfeld, the CEO of Investors Overseas Services (IOS) Ltd., a dominant financial fund at the time. 

• The Milestone: It served as an exclusive corporate trophy gifted to top-performing financial traders who surpassed $1,000,000 in revenue sales, earning them the title of a "Million Dollar Associate". 

• Production Scale: Patek Philippe manufactured just over 1,000 examples of this specific reference between 1968 and 1971.

• FeatureSpecification DetailsCase Dimension35mm diameter, featuring a slim, lugless "Disco Volante" profile (~9.6mm thick).MaterialSolid 18k Κίτρινος Χρυσός case with an integrated hand-crafted Milanese mesh gold bracelet.ΜηχανισμόςUltra-premium Caliber 27-460M automatic movement featuring 37 jewels and an 18k gold rotor stamped with the Geneva Seal.Dial DesignSatin champagne sunburst dial decorated with thin black Roman numerals and a date window at the 3 o’clock position.Provenance MarkersCaseback explicitly engraved with "IOS Million Dollar Associate" alongside the IOS logo. Some rarer variants feature an "IOS" imprint directly on the dial at 6 o'clock.