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Donald Duck, Patents, and Ping Pong Balls

Donald Duck 1949There is a well-known story among IP lawyers about prior art coming from, of all places, a comic strip.  The story not only explains how prior art works in layman’s terms, but also makes the “treasure hunt” even more mysterious!


In the mid 1960’s, a Dutch ship carrying thousands of sheep sunk off the coast of Kuwait.  The shipping company and its insurer were liable for the ship, not only the cost of the vessel itself but for the damage that the rotting cargo could have on the freshwater harbor.  In short, the ship had to be raised quickly from the ocean floor.

The Danish inventor Karl Krøyer, also known for patenting a sugar substitute and a highway surfacing material, was called upon for a solution.  He and his team successfully devised an idea to pump millions of small foam-like balls through a tube into the hull of the ship.  The foam balls would make the ship buoyant enough to float toward the surface.  The plan worked, and the event made news around the world.  In the aftermath, some media accounts drew comparisons from the real-life event to a 1949 Donald Duck comic strip, in which the characters raise a sunken yacht by pumping ping pong balls into it.

Here’s the part of the story that we can’t confirm, but is the reason for its fame in the IP world: Krøyer applied for patents in Great Britain and Holland for this method of ship-raising.  He recieved a patent in Britain, but evidently not in Holland.  As the story goes, the Dutch examiner cited the Donald Duck cartoon as evidence of prior art for the ship-raising idea, and denied the patent.

Moral of the Story: Non-Patent Literature

The story deserves some skepticism because, as with any form of law, nothing is cut and dry in patent examination.  In fact, our own community of Researchers debated on the validity of prior art coming from fiction, and mentioned the Donald Duck story.  As one commenter suggested: “A science-fiction novel might describe an invention without going into details. While this will describe the basic idea behind the invention, it does not enable the skilled person to construct the invention.”  “Enabling” is a key facet of prior art.  On the other hand, if one can demonstrate obviousness, then a patent can be rendered moot.  In this case, Donald Duck may have succeeded in making the idea obvious. 

Putting aside these unknown details, the main idea of the story remains relevant in prior art searches.  Prior art can come from anywhere, and often from unexpected places.  The winning references in Article One Studies are most often “non-patent literature”—meaning any documentation of an idea that’s not a patent or patent application.  Ideas come in many forms, and they need not be in the form of a previous patent in order to show that a current patent is invalid.

Non-patent literature is especially valuable because it can describe a piece of technology in a completely different context than an application or patent might.  People who perform initial prior art searches may not have the time, resources, or highly specific expertise required to find “outside the box” non-patent literature.  That means Article One Studies are a perfect opportunity to take a stab at a hunch or a seemingly weird idea about where a technology might fall across disciplines.  Take a risk; you might just strike NPL gold!

For more detail on the Donald Duck stoy, check out Ius Mentis and Comic Book Resources.

Bonus Video!

The ever-popular Mythbusters television show on Discovery Channel actually tried to raise a ship Donald Duck-style.  While it doesn’t touch on the patent or IP sides of the story, it’s worth sharing because it’s so darn cool!


The Mythbusters used conventional ping pong balls, just like the cartoon, rather than Mr. Krøyer’s high-tech foam-like material. (Albeit on a much, much smaller ship).  Enjoy!



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