What are preferred embodiments?
In any other context besides patents, “preferred embodiment” would sound quite strange. Yet, the term is used so commonly and frequently in utility patents that the inexperienced reader might be tempted to gloss it without understanding its meaning. Why does a specification have to repeat it 75 times? What exactly is the inventor (or, more likely, the patent attorney) trying to say when something is referred to as a preferred embodiment? Is there something the patentee is trying not to say when they use that term? Let’s find out.
To put it simply, a preferred embodiment is an example of an invention. An invention might be singular in the sense that it consists of a core concept or idea, but there may be multiple examples of how that concept would play out. For example, certain core features can be replaced with alternate features that accomplish the same purpose. An invention may comprise a variety of different combinations of features. Certain structures or steps may have variations that would produce that same result.
How is the description of the invention different than claims?
A brief background into the parts of a utility patent will help provide a more thorough understanding of this peculiar term. Every utility patent will have at least two parts:
- description of the invention; and
- claims.
The terms “preferred embodiment” will show up in the description, and not in the claims. This makes sense because the description is the section of a utility patent where the inventors flesh out the details of the concept and the various examples that would embody their idea.
In most cases, the usage of preferred embodiment occurs most frequently in the section of the patent entitled Detailed Description of the Preferred Embodiments. This is the written section of the specification that contains numerals referring back to the drawings (e.g., “In FIG. 1, the device 10 comprises a portion 20 . . . ).
Does a preferred embodiment limit your patent?
Your patent rights are defined by the claims, and not by the description. It would be a mistake to assume that a patent covers what you see in the drawings and written description. That being said, the description of the invention does provide context to what is recited in the claims.
While a particular preferred embodiment shown in your description should not confine your patent rights to only that example, such an embodiment can place parameters or boundaries on what certain claim terms mean. Just because your claims recite a particular structure does not mean that you have free range to cover all possible structures that may be unrelated or even opposite to your shown structure.
How to decipher the preferred embodiment code
Perhaps one helpful way to interpret “preferred embodiment” is to think of the author saying: “This is one example of my invention, but not the only way it can be done.” The inventor/patentee is saying that there may be other ways to accomplish the same purpose or result, and that the claims could possibly encompass those other ways.
That is also the reason why other terms frequently show up in the description, such as “preferably,” “optionally,” “alternatively” and so forth.
