Donald Duck and the Sunken Yacht Patent

Did you know that Donald Duck and his nephews prevented a patent from being filed? In 1949, they saved Scrooge McDuck’s ship using a proprietary technique that wasn’t attempted by anyone else for 15 years!

The Story

In September of 1964, a freighter called “Al Kuwait” capsized at the docks in Kuwait’s harbor. The ship was carrying 5,000 sheep, which threatened to contaminate the city’s drinking water supply. The city needed a method to raise the ship as quickly as possible. Cranes would take too long, and would risk breaking the ship.

Al-Kuwait Boat Donald Duck

Courtesy of New York Times


The Solution

Luckily, the Danish inventor Karl Kroyer came up with a method of raising a sunken ship. He filled the ship with 27 million plastic balls made of an “expandable polystyrene foam” that weighed 65 tons! The total cost to save the ship was high, almost $345,000, but it saved the insurance company almost $2,000,000, according to a contemporary New York Times article (8 March 1965, page 58). 

Salvage Principle Karl Kroyer Donald Duck

Courtesy of

The Patent

Kroyer received patents for this method in the United Kingdom (GB 1070600) and Germany (DE 1247893). The patent showed “buoyant bodies inserted into a sunken vessel through a tube from a salvage ship”.

However, when Kroyer applied for a Dutch patent (NL 6514306), the application was not approved. The Dutch Patent Office found an old issue of the Donald Duck magazine which shoed the same invention!

Kroyers Patent Donald Duck

Donald Duck

In the 1949 Donald Duck story “The Sunken Yacht (by Carl Barks), Donald and his nephews raise Scrooge McDuck’s ship by filling it with ping pong balls through a tube.

Donald Duck Sunken Yacht

Since ping pong balls are considered buoyant bodies, and they were fed through a tube, the Donald Duck story shows the same technique that was claimed through the patent. If you’re curious, the official name for this is a “novelty-destroying prior art”.

Images from 'The Sunken Yacht', © 1949 Walt Disney Corporation.

Images from ‘The Sunken Yacht’, © 1949 Walt Disney Corporation.

Have you ever heard this story before? Let us know your thoughts in the comments!