Linguistic Modals Used in Patents

The linguistic constructions collectively called "modals" have a limited, but important, place in the written portion of patents. Modals are generally found in the background and brief description of the invention (e.g., objectives of the invention) portions of the patent specification, but not generally in claim recitations.

Modals include verbs and adverbs that express the concepts of possibility, probability, necessity, obligation, and permission. Core verbs (i.e., "auxiliary verbs") expressing modality are: may, might, can, could, will, would, shall, should and must ["Adverbs and Modality in English", Hoye, 1997, 058221535-8].

Modals can also be described as showing emotion (e.g., imperatives) and, in some cases, predicting the future (e.g., probability and possibility). In the Background portion of patents, the application writer describes a general "need" for the invention and how this need "will" be fulfilled. Here are a few examples:

There has been a long standing need for ..., which this invention fulfills.
An objective of this invention is to be able to ....
This invention will ....

By contrast with predicting a future possibility or probability, patents describe actual inventions, i.e., a concept that has been (supposedly) reduced to practice and is expected to work as described in the detailed portion of the specification, including any necessary experimentation within the capability of someone of ordinary skill in the art.

In the detailed description of the invention, a general modal expression can be used to describe the possibility of using alternatives in an invention. This sentence/paragraph construction should be included to avoid overly limiting the legal protection only to the known embodiments described in the specification. Here are examples:
The device can include alternative .... (features, materials, arrangements, etc.)
The material can be modified by substituting ... with ... (features, materials, etc.)

In the one-sentence recitation of a patent claim, words describing a probability or possibility should be avoided, since they can render the claims as being unclear or indefinite under 35 U.S.C. 112.

Francis Lorin
siberkhem.com