If someone copies the functional elements of a patented device, they may be found liable for patent infringement. To determine whether an infringement has occurred, a court looks at each “claim” of the patent. A patent may have any number of claims, but each claim is a one sentence description of the invention. If you were to look at a claim in the abstract, you would probably have no idea what the invention was. That is because the claim lists only the essential elements of the invention, just enough to define a combination of elements no one has ever combined before. If anyone makes, uses, or sells something with every one of the claimed elements, they infringe the patent. If they can avoid using even a single element of the claim, they do not infringe that claim.
The key therefore, and the point where skillful drafting determines the difference between a narrow patent and a broad patent, is to include only the minimum number of elements in the claim. This makes it difficult for a would-be infringer to eliminate any single element. In a patent infringement trial, the issue revolves around whether if each element of a patent claim, or its equivalent, can be found in the accused device. If the accused device does indeed include every element of the claim, the device infringes that claim and the infringer is liable to the patent holder for associated damages.
Regardless of the number of claims included within the patent, if the accused device infringes a single claim, the infringer is liable for the same amount of damages as if the infringer had infringed every claim of the patent. If the accused infringer is found to have infringed the patent, under the patent laws the court may grant an injunction and/or award the patent holder damages in the form or lost profits. By law, in no case may a court award compensatory damages which are less than a reasonable royalty. In the case of willful infringement, the court, by law, may award treble damages and attorney fees. Tomorrow, Internet Patents.