Omit Unnecessary Elements

Omitting unnecessary elements is critical to drafting short claims. Consider the very first person to invent a chair of any type. He claims "a chair having four legs, a vertical back, held together with nails, screws, bolts or dowels". That claim is way too narrow! The seat doesn't have to be flat, the back doesn't have to be vertical, the chair could be built with some other number of legs, and the seat, back, and legs could be held together with connectors other than those listed. The following chart shows how the original claim should be reworded to omit unnecessary elements.

Figure 44 — All Unnecessary Elements Should Be Omitted

Most patent attorneys are adamant in saying that they eliminate all of the unnecessary elements in their patent claims. But the facts belie their words. One can pick almost any patent, in almost any field, and find claims that are bloated with unnecessary elements. Consider the following claim in U.S. 4958145 for a sensor that detects improper posture while lifting an object:

1. A back incline indicator for indicating whenever the back of a user is bent beyond an acceptable limit, comprising:

(a) a hollow casing having a side plate,

(b) attaching means on the casing for securing the casing to the back of a shirt collar of a user with the side plate resting against the back of the user,

(c) electric audio signal means in the casing having an electric circuit including a source of electric potential, and

(d) electric tilt switch means in said electric circuit and mounted in said casing for closing said electric circuit and activating said signal means when said casing side plate is disposed in a plane which forms with a vertical line an included angle of a predetermined magnitude and for opening said circuit and deactivating said signal means when said casing side plate is disposed in a plane which forms with a vertical line an included angle of less than said predetermined magnitude.

That claim is just terrible. Why recite that the casing is hollow? For that matter why recite a casing at all? It is perfectly possible to produce the device as a solid electronic device, similar to an RF (radio frequency) tags. In that embodiment there would be no casing at all, let alone a hollow casing. The point is that the housing has nothing whatever to do with the invention. Recitation of "a housing" would therefore have no effect on patentability. The same analysis, of course, applies to several other elements in the claim. There is absolutely no reason that the claim should recite an attaching means for attaching the casing to the back of a shirt collar. The device could just as readily be worn on the front of the user. If the element is not needed for patentability, it should be eliminated (at least from the broadest claim).

U.S. 5749838 provides another good example:

1. A posture training device, comprising:

a rigid frame positionable against the back of a person at the intersection of a backbone curve defined by the person's backbone and a transverse curve thereof;

a rigid generally box-shaped hollow module disposed in the frame and movably engaged therewith between a good posture position, corresponding to respective first convexities of the curves, and a poor posture position, corresponding to one or both of respective second convexities of the curves, each second convexity being greater than the respective first convexity;and

a tactile signal generator mounted on the module for generating a tactile signal when the module is in the poor posture position.

This claim is also a waste of good paper. It makes no sense to require the device to be attached to a rigid frame. Why not just say a frame? Indeed, why recite the frame at all? The rest of the claim is also replete with unnecessary elements, including the rigid, box-shaped, hollow module, and the business about one convexity being greater than another. The invention is providing a posture sensor with tactile signal generator. Why not just claim this as "A posture sensor with a tactile signal generator?"

U.S. 6059576 (May 2000) "Training and safety device…" provides another example of a bad patent from the same field. Here, claim 20 is quite short, and one would think that in such a short claim the attorney would have omitted unnecessary elements. But he didn't.

20. A method to monitor physical movement of a body part comprising the steps of:

attaching a portable, self-contained movement measuring device to said body part for measuring unrestrained movement in any direction;

measuring data associated with said physical movement;

interpreting said physical movement data based on user-defined operational parameters and a real-time clock; and

storing said data in memory.

Here, the claim requires that the device measure unrestrained movement in any direction. First of all, if the device is measuring movement, what difference does it make whether the movement is restrained or unrestrained? Second, the limitation of "movement in any direction" should have been jettisoned during drafting. All a competitor has to do to circumvent the claim is to produce a device that cannot measure movement in a given direction, such as straight up and down. Third, even if the "any direction" element were needed for patentability, it makes no sense to include the element of a "real-time clock" in the claim. If the invention is really nothing more than the combination of (a) a sensor that works in any direction and (b) a real-time clock, the inventor would have been better off spending his money on a good vacation rather than securing a patent.

Here is yet another example. The following claim is directed to a reader for laboratory tests. The chemistry is performed inside a flexible bag that has multiple chambers, and the machine uses feet to move the fluids from chamber to chamber. The bag is inserted into the machine at an opening, but the chambers can be anywhere within the bag. The invention relates to repeated heating and cooling of the fluids, and it was completely unnecessary and inappropriate to recite limitations with respect to the processing stations positioned along the opening.

1. A thermal cycler comprising:

a processing unit having an opening to receive a sample vessel containing a sample, the processing unit having a first processing station and a second processing station positioned along the opening,

the first processing station including a first compression member adapted to compress the sample vessel within the opening and a first energy transfer element for transferring energy to the sample at the first processing station…

What then is to be done about unnecessarily bloated claims? The best way to prevent unnecessary elements from slipping into abyss of dismal claiming is to have another patent attorney review the claims before they are filed. Even without knowing much about the specific technology, a fresh reading by the other attorney can go a long way towards eliminating unnecessary claim elements. When the attorney is forced to justify every single word in his claim, his drafting of claims tends to become much more succinct. That practice is also incredibly useful for the second reader. Finding mistakes in the work of others makes it much easier to find similar mistakes in one's own work.