Produced from 1956 to 1962, the BMW 503 made its debut alongside the BMW 507 at the 1955 Frankfurt Motor Show. It received an update in 1957, with the earlier cars referred to as Series I and the later cars Series II; the former were distinguished by a column gear shift, hydraulic window lifts, and for the cabriolet, a hydraulic-operated hood. All were powered by a 3.2-liter V-8 engine that the factory rated at 140 horsepower, and clothed in svelte aluminum coachwork provided by Bertone.

This BMW 503 Series I Cabriolet is one of just 78 such examples constructed. Imported to the United States sometime during the 1970s or 1980s, it was then owned by a Mr. Henri de Forrest of Van Nuys, California. Prior to his ownership, chassis 69178 was registered in California as 1BGS 994, and Mr. de Forrest kept this plate until 1981, when he changed the car’s registration to BMW57. Historic imagery on file depicts this lovely BMW on Mr. de Forrest’s driveway, sporting the same white paintwork, black soft-top, and blue-and-white vinyl upholstery with which it still presents today.

As per the sales agreement on file, Rudi Klein’s Porche Foreign Auto Wrecking purchased this 503 Cabriolet in June 1984 for the princely sum of $11,000. It was subsequently brought to the storage buildings at Porche Foreign Auto’s yard and remained there—quietly interred among Klein’s personal trove of significant vehicles until July 2024, when RM Sotheby’s staff arrived on-site to catalogue and photograph the entire collection.

Today this remarkably rare, coachbuilt BMW remains in the same configuration as when Rudi Klein purchased it 40 years prior, and as such the condition is reflective of sitting for such a length of time. Lying in wait for 40 years, this BMW 503 Series I Cabriolet presents as an excellent foundation for a restoration.