Patent Article by William S. Ramsey, P.C.


William S. Ramsey
Attorney at Law
410-740-2225 or email:
Not Legal Advice.

Research in Motion, Ltd. (RIM), manufacturer of the BLACKBERRY personal digital assistant, has been found by a jury to have willfully infringed a patent on portable text messaging which belongs to NTP, Inc. What does patent infringement involve? How does one avoid it

Patent infringement involves making, using, selling, offering to sell or importing anything which infringes (that word again) a valid patent claim. Infringement is a strict liability tort. It occurs whether or not the infringer deliberately infringes or even knows of the existence of the patent. Willful infringement is infringement with actual knowledge of the existence of the patent and can carry increased penalties. Every person has a duty to avoid patent infringement.

Every patent consists of a written description, drawings in appropriate, and at least one claim. The claim is like a boundary – it defines exactly what the invention is. A patent claim clearly defines what cannot be done without infringing the patent.

For example, suppose you have invented a nuclear powered car and have claimed it as follows: A car comprising a body, a nuclear reactor, and 4 wheels.

Is the patent infringed by a car comprised of a body, a nuclear reactor, and 5 wheels? Yes, because every element of the claim is contained in the accused car. A car with 5 wheels necessarily is a car with 4 wheels. This is called literal infringement, which occurs when the accused device contains all elements of the claim.

Is the patent infringed by a car comprised of a body, an engine, and 3 wheels? No, because the element "4 wheels" is missing in the accused car. Here there is no literal infringement

If this were all there is to infringement, patents would fulfill their purpose of clearly delineating the boundaries of the protected invention.

The basic problem is that inventions are objects, chemicals or processes. Patent law, however, requires the description and claims be stated in words. The translation from things to words is always difficult. It is very hard to foresee and adequately claim all the variations of an invention legitimately protected by the patent.

So the Supreme Court in 1853 created the concept of infringement by Doctrine of Equivalents. In that case, Patent No. 5,175 covered a railroad coal car which, because of shape of the car body, was capable of carrying twice the weight in coal of previous cars. The relevant part of the claim was the phrase "in the form of a frustum of a cone"

The accused car body was not in the form of a cone but had the form of a pyramid having 8 sides. In cross-section the patented car body was a circle. The accused car body in cross-section was a polygon with 8 sides.

Clearly the accused car body did not literally infringe the patent. The Supreme Court, however, decided the accused car body nevertheless did infringe the patent. A polygon with 8 sides was equivalent to a circle in this case.

The Doctrine of Equivalents has been battered and modified over the years but survives. It is rare that an accused device will copy exactly every element of a patented invention. Patents would be greatly reduced in value if only literal infringement were recognized. The Doctrine of Equivalents seems to be involved in every infringement case.

The Doctrine of Equivalents is in tension with the idea that a patent clearly tells the world the boundaries of the claimed invention. A lawyer is always needed to evaluate
the breath of a patent claim.

There is a lesson here for RIM and for all of us. Always have a Plan B. RIMıs position with respect to NTP would be vastly improved if RIM could immediately install new and different portable text messaging software. That doesnıt appear to be the case, however, leaving RIM somewhat at the mercy of NTP. Itıs always good to ask the question – what happens if our lawyers are wrong? Who will go out of business? They or us?