International Watch Company

The International Watch Company, also known as IWC, is a high-end Swiss watch manufacturer located in Schaffhausen, Switzerland. IWC is an active member of the Federation of the Swiss Watch Industry FH. IWC Schaffhausen is notable for being the only major Swiss watch factory located in eastern Switzerland, as the majority of the well-known Swiss watch manufacturers are located in the western part of the country.

The company has kept detailed records for every watch that has left the factory since 1885. Since that date, details of the caliber, materials used, and cases have been entered into the records. In the case of later models, these also include the reference number, delivery date, and the name of the authorized dealer. For a small fee, the owner can obtain precise information about their watch, as long as the watch is at least ten years old. The company claims that its service department has the parts and is capable of repairing and maintaining watches from every era since IWC's foundation in 1868.

Some modern movements in watches of IWC are based on movements supplied by ETA and heavily modified by IWC. This is common practice by many high end watch marques. In particular, the Caliber 30110 is a modified ETA 2892A2, and the Caliber 79230/79320/79350 is a modified ETA/Valjoux 7750. Like all high end automatic watches, IWC watches lose or gain approximately 4 seconds a day. Movements not based on ETA movements include the Caliber 5000 and the Caliber 8000, which use the Pellaton winding system, and the pocket watch movements used in the Portuguese F.A. Jones and other IWC pocket watches. IWC also used a JLC meca-quartz movement in their older Portofino chronographs.