My last column was the first of two columns discussing some of the most common misconceptions or myths about patents.  Here is the second part, starting with number five on my list. 

  1. A Patent Does Not Give the Patent Owner the Right to Practice the Invention.

Inventors and patent owners often assume that a patent gives them rights to practice the patented invention, i.e., freedom from infringement.  Not true.

A patent is a grant to its owner of the right to exclude others from making, using, offering to sell, and selling the patented invention in the United States, or importing the invention into the United States.  These rights are called exclusionary rights.  A patent does not provide its owner with the rights to do these things.  An invention may be patentable but still infringe another person’s patent.  In such a case, the patent owner may have a patent on the invention but cannot make or use the invention unless they obtain a license from the owner of the patent that is infringed.

  1. Patents Do Not Infringe Other Patents.

A patent cannot infringe another patent.  Only a machine, article of manufacture, composition of matter, or process can infringe a patent.

As stated above, a patent gives its owner the right to exclude others from making, using, offering to sell, selling, or importing the patented invention.  The patent is infringed if any of these acts are committed in the United States without the patent owner’s permission.  Thus, there is no infringement unless someone makes, uses, offers to sell, or sells the invention in the United States, or imports the invention into the United States.  An invention described in a patent may infringe another patent, but only if it is made, used, offered for sale, sold, or imported in the United States.  The patent itself is not an act of infringement.

  1. Patentability and Patent Infringement are Not the Same Thing.

Inventors often think that if their invention is patentable, then it cannot infringe other patents.  Not so.  Patentability and patent infringement are two different things.  An invention may be both patentable and infringe an existing patent.  In both cases, the starting point of the analysis is the claims.

To determine if an invention is patentable, the invention, as it is claimed, is compared to what is known in the field (the prior art).  In general, prior art includes written documents (such as other patents, published articles, catalogs, and websites), as well as actions by the inventor and third parties, that exist before the patent application is filed.

The first requirement of patentability is that the claims must be novel (new or different) over the prior art.  The test for novelty is performed by looking at each element of the invention as claimed.  If all of the elements of the claimed invention are present in a single prior art reference, then the invention is not novel and is said to be anticipated by the prior art.  The invention is not patentable.

The second requirement of patentability is that the claims must be nonobvious over the prior art.  The invention is obvious if the differences between the invention and the prior art are such that the invention, as a whole, would have been obvious at the time it was made to a person with ordinary skill in the art.  Unlike the test for novelty, the test for obviousness is not limited to a single prior art reference – any number of references can be combined to render an invention obvious.  For obviousness to be found, every element of the claimed invention must be present or suggested in the prior art, although not necessarily in the same reference.

To determine if an invention infringes an existing, in force (not expired) patent, the claims of the patent in question are compared to the invention (in a patent infringement action, the district court first interprets or construes the claims to determine their meaning and scope).  If each element of a claim is present in the invention (literally, or in some cases, by an equivalent), that claim is infringed.  Only one claim need be infringed for the patent to be infringed.

Thus, although it sounds counter-intuitive, an invention can be patentable over a prior art patent and, at the same time, infringe the same patent.