Design patent infringement

Three-way visual comparison test
Three-way visual comparison test

Design patent infringement isn’t based on exact copying. Rather the test is if an “ordinary observer” will see “substantial similarity”. 

Determining if a particular design of interest does, or does not, infringe upon another design patent is an interesting gray area of intellectual property law.

According to the 2008 Federal Circuit ruling in Egyptian Goddess, Inc. v. Swisa, Inc.” 543 F.3d 665: to infringe, a given design does not have to be an exact copy of another design patent.  Rather, the question is one of “substantial similarity” under the “ordinary observer” test.

Great — what the heck is this, and how does this test determine design patent infringement?

The underlying idea is that customers looking to purchase a design patented product “Y” should not be deceived by similar looking product “X”.

So as a practical matter, you should run this test using ordinary observers. Realize that if you personally are involved, it may be difficult for you to be fully objective.  In this case, you are probably not a suitable “ordinary observer”.  Instead, determine if disinterested outsiders see “substantial similarity“.

Although sometimes the differences between a given design and a particular design patent may be so great that no further comparisons are necessary, sometimes the designs are close. Here a “three-way visual comparison test” can be useful. This test can be done by making a composite illustration showing the patented design on one side, the “accused design” (i.e. the design being investigated) in the middle, and other designs representing the closest prior art on the other side.

Essentially it is a pattern recognition problem.  The idea is to use the prior art examples to instruct the ordinary observers as to how much variation is typical in this field.  Then the ordinary observer can determine if the design of interest is overly close to the design patent of interest, or not.

This sort of approach was used to compare handheld blender designs in Braun Inc. V Dynamics Corp. 975 F.2d 815, in 1992.  As you can see in the above image, the “accused design” was visually much closer to the patented design than it was to the closest prior art. The court determined that the “accused design” was in fact infringing.

The best times to consider these issues are before you start producing and selling a new design. So if you have a new design that you are worried about, get the opinion of some neutral outsiders ASAP.  Indeed, consider running some focus groups as appropriate. If things look too close, consider making some further design changes, and trying again.

Design patents

For stronger design patents – less detail can give you broader coverage, so consider turning some solid lines into dotted lines.

design patent
Design patents can be like the disappearing Cheshire Cat

On the surface, design patents – a patent that covers the ornamental appearance of an article of manufacture, seem simple. File multiple drawings showing your design from multiple angles – often all six sides of an imaginary cube, as well as in perspective. If (under a famous court case called the Egyptian Goddess test), an ordinary observer (familiar with the prior art designs of similar products) will confuse someone else’s product with the patented design, then there is infringement.

This raises interesting questions of pattern recognition. The problem is often explained by analogy to the Cheshire Cat from Alice in Wonderland.  How much of the cat do you need to see in order to identify it as a Cheshire Cat?

In a design patent, the parts that are required are shown in solid lines, and the optional parts are shown in dotted lines.  As more and more solid lines are turned into dotted lines, the design becomes more general, but of course at some point, the design then becomes too general to be unique or even recognizable.

When broad coverage of a design is desired, consider filing multiple versions (or alternatively continuations) of a design patent.  Narrower but safer versions can have more solid lines; in riskier but broader versions, replace the less essential solid lines with dotted lines.  Perhaps a subset or outline of your product is distinct enough to warrant design patent protection?  If you think that your design may have multiple distinct sections, consider putting in dotted lines to show these sections in the initial filing, since the USPTO won’t let you do it later.

Compared to utility patents, design patents are relatively inexpensive to file, and relatively easy to get.  However again, the design patent is only for the artistic and non-functional aspects of the design. Design patents now have a 15 year lifetime, and no maintenance fees are required.

A few more tips — design patent examiners have a well-developed ability to detect inconsistencies between drawings and/or ambiguity in drawings.  Problems can often be avoided by first making good quality 3D CAD files, and then making these 3D CAD files available to the patent attorney.

International design patents

Good news for US inventors who are interested in filing international design patents.

Design patents are for unique designs for something that otherwise functions according to prior art.  In the US, inventions that function differently from prior art are covered by “utility patents”, while the unique ornamental appearance of a design is covered by a “design patent”.  Design patents are relatively easy to get, and presently last 14 years.

Although the Patent Cooperation Treaty (PCT) has provided utility patent inventors and owners with a simple (if expensive) way to begin to file their utility patents in various countries, the PCT system does not provide a mechanism by which an American design patent can be filed internationally.  This was a nuisance, because design patent standards can differ substantially from country to country, which made the process of obtaining international design patents (industrial design applications) complex and expensive.

Fortunately this is about to change.  On December 19, the Hague Agreement Concerning the International Registration of Industrial Designs was signed into law in the US.  The Hague Agreement can be viewed as a “PCT-like application” for design patents.

In addition to providing a standardized procedure for international filings, the Hague Agreement also extends the life of design patents to 15 years.

This agreement has actually been in the works for some time.  The original Hague Agreement was established in Geneva in 1999, and was ratified by the Senate in 2007!