Home > claim construction > Beware the Object of the Invention

Beware the Object of the Invention

One thing that can be good when working as a lawyer is to have a way with words.  As a patent prosecutor, you must also be very careful with your words.

It is well known that prosecution history estoppel can be used to limit the scope of patent claims.  A recent decision from the Middle District of New Carolina also reminds prosecutors of the need to have caution in drafting a patent’s specification.

In BASF Agro B.V., Arnhem (NL), Wädenswil Branch, et. al. v. Makhteshim Agan of North America, Inc., et. al., the accused infringer (Makhteshim) argued that the patentee (Kimura, who assigned his patent rights to BASF) disclaimed claim coverage over Makhteshim’s method of applying insecticide.  Interestingly, Makhteshim argued that the disclaimer was in a single sentence of the patent’s specification (U.S. Pat. No. 6,414,040), in which the patentee described the objects of the invention.

In its decision finding noninfringement, the court agreed.

The court stated (at pp. 18-19):

The use of an exterior barrier as a required element of treatment is prior art as defined and clearly disclaimed by Mr. Kimura.  Under Northern Telecom, because Mr. Kimura clearly and unmistakably disclaimed the use of a prior art barrier, the prior art barrier and Mr. Kimura’s invention became “mutually exclusive.” See Northern Telecom Ltd., 215 F.3d at 1297.  Thus, by definition, one practicing a form of treatment which requires both an exterior barrier element and an interior loophole element is not practicing Mr. Kimura’s invention. This court finds that Mr. Kimura’s description of his invention as “a termite treatment without barrier,” (U.S. Pat. No. 6,414,040, col. 1, ll. 43-44), excludes barrier treatments from the invention and therefore the combination of a barrier treatment and Mr. Kimura’s loopholes does not infringe the patents at issue.

 The entirety of Kimura’s disclaimer read: “Another object of the instant invention is to provide a termite treatment without barrier,” with the key word being without.  The court found this to be a clear disclaimer of claim scope, and contrasted this disclaimer to cases where the patentee was either silent on the issue, or stated that certain features were merely undesirable, in which cases courts do not find disclaimers of claim scope.

  1. January 25, 2012 at 11:18 AM

    I have been trying to get away from using the expression “. . . another object of the invention is . . .” because it seems like I could easily leave out one of the “objects” of my invention and thus limit myself. Some applicants dispense with the Summary altogether. At some point, there probably was some ruling that said such language was best practices because it seems like many patents and applications use the “object of the invention” construction. Do you know the history on this expression? Do you use it when writing your applications?

  2. January 25, 2012 at 11:52 AM

    Good question regarding history of the expression. I don’t know its way-back history, but it’s part of the patent rules in 37 CFR 1.73, which states: “§ 1.73 Summary of the invention. A brief summary of the invention indicating its nature and substance, which may include a statement of the object of the invention, should precede the detailed description.”
    As for writing applications, I have now transitioned away from prosecution and now do litigation exclusively. However, when writing, I was taught always to avoid using the word “invention” and to avoid characterizing any particular “thing” as “the invention.”

  1. No trackbacks yet.

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out /  Change )

Google photo

You are commenting using your Google account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s

%d bloggers like this: