Patents That Are Dominated By Other Patents
Obtaining a patent generally provides the patent owner with the ability to prevent others from making, using, selling, offering to sell or importing the patented invention unless permission has been given by the owner. However, owning a patent does not grant the patent holder the absolute right to make and sell the patented invention, and it is possible that doing so may be an infringement of another unexpired patent. This concept is probably best illustrated by the following scenario.
If a first person invents a machine with parts A and B and files a patent application, a patent may be granted if the combination of parts A and B is new and unobvious. The first person then has the right to prevent others from making, using, selling, etc. a machine with parts A and B. A second person may invent a machine that includes parts A and B, but also includes part C which improves the operation of the machine as compared to one with only parts A and B. The second person may also be granted a patent on the machine with parts A, B and C if that combination of parts is also new and unobvious.
But if the first person’s patent has not expired, the second person will not have the right to produce and sell a machine with parts A, B and C without getting permission from the first person. Since a machine with the combination of parts A, B, and C includes parts A and B, it infringes the patent of the first person. The addition of part C to the machine, while deserving of a patent, does not avoid infringement of the first person’s patent.
Submitted by Patent Attorney Jeff Proehl