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I have absolutely zero understanding of patent law, and have only just discovered that it's illegal for me to reproduce a game called "9 Square in the Air" for personal use due to two "ornamental design" patents they were able to secure, and because of their price purchasing is out of the question as a college student. It may sound ridiculous, since I'm well aware no one is going to "come after me" over something I build for my backyard, but I'd like to obey the law.

My friend has argued that all I have to do is modify the design in some manner in order to achieve enough of a change for it to be legal. My question then stands, what is enough of a change for a patent to no longer apply?

For example, if the result is still 9 squares in the air using PVC piping, does it really matter what else I change since it will perform the same function?

The two design patents: http://www.google.com/patents/USD656995 http://www.google.com/patents/USD650445

A patent created by some prior to them for the game idea itself (no idea how they got away with that): http://www.google.com/patents/US7608000

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I have had the same problem of wanting to build one myself. Would you be able to build it out of wood instead? would that bypass the patent restrictions, if it wasn't pvc pipe? –  user3735 May 6 '13 at 22:46
The materials are not indicated in the patent, so I'm going to give an (un)educated answer that no, that probably wouldn't make a difference. –  xtraorange May 7 '13 at 2:41

2 Answers 2

USD656995 is an "ornamental design" for a 9-square game that includes telescoping legs. The test of another design is that it won't be mistaken for the patented design. Nine circles or hexagons would clearly qualify. If squares are required, then have the legs mid-span instead of at the corners, or make them wider flat plates at the top instead of the same size as the legs, etc.

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Thank you for your response! Unfortunately none of the above suggestions are possible with PVC piping, though I greatly appreciate the input. If it has the same base design, but adds more to it (i.e. if I ran a PVC pipe around the perimeter at mid-height), would that be enough, or does it need to modify the base design rather than add to it? –  xtraorange Mar 13 '13 at 17:59

Any improvement that you make to the product or item.

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No - it needs to be a change in the external look. Improvement implies functionality. –  George White Mar 13 '13 at 8:24
Paul, no offense, but you are way off. Search design-around strategies. –  Yorick Mar 16 '13 at 14:43

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