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September 2017 Newsletter

Vol 10, Issue 3

Introduction to Reading Patent Claims

By Thomas R. Knight


A patent document is generally divided into two broad sections: the Claims and the Specification.

The Claims define the actual scope of a patent's protection. Broad protection is generally desirable, but claims must be narrow enough to be new and non-obvious to be allowable over the prior art (anything patented, described, or already known in the world). Most patents include both broad and narrow claims. 

The Specification constitutes the remainder of the document, which includes both text and drawings. The Specification provides definitions, details, and specific examples such that a person having ordinary skill in the art could practice the claimed invention. Providing specific examples does not usually limit the scope of the patent. 

Reading the Claims

There are two types of claims: Independent and Dependent.

Independent claims do not reference any other claims and, thus, stand alone. Independent claims define the broadest scope of protection. 

A dependent claim is one that references another claim, adding further limitations to the claim it depends upon. Therefore, for any limitation added in a dependent claim, the claim it depends upon does not usually require that limitation. Dependent claims also provide backup protection if a broader claim is later held to be invalid.

Claims begin with preambles, which can add context. If the preamble ends with "comprising," the claim covers anything having at least the elements listed. In contrast, "consisting" is closed-ended. Thus, a 3rd party device having all claimed elements, but also more, infringes a claim ending with "comprising," but not one ending with "consisting." 


Claim 1:  A wagon, the wagon comprising four sides, a handle, and wheels.

Claim 1 is independent, not referencing any other claims. It is open-ended based on using "comprising."

Claim 2:  The wagon according to claim 1, wherein the wheels are four air-filled tires.

Claim 2 references (thus, depends upon) claim 1. Claim 2 claims another wagon like claim 1, but adds that "wheels" means four wheels, and specifically air-filled tires.



Claim 1 does not limit the number of type of wheels, thus any number or type is potentially covered. Since the wagon claimed in claim 2 limits these to four and air-filled, claim 1 is not limited to four or air-filled. Thus, without explicitly claiming it, claim 1 also covers the six wheeled, solid version shown above. Likewise, claim 1 covers wagons having more than those with four sides, a handle, and wheels, such as those with an added seat. 


Andrus Included on 2017 IAM Patent 1000 List

Andrus was once again included in the guide entitled IAM Patent 1000 - The World’s Leading Patent Practitioners. The IAM Patent 1000 is a standalone publication that identifies individual and firm expertise in all major areas of patent law and practice. Through an extensive research process by a team of highly qualified analysts, the publication identifies the top patent practitioners and law firms in 40 of the world’s most important jurisdictions and 20 U.S. states. In addition to firm-wide recognition, Joseph Kuborn, Aaron Olejniczak, Peter Holsen and Tambryn VanHeyningen were featured individually, based on positive feedback from clients and associates.


Andrus Sponsors MBA Golf Outing Benefiting the Milwaukee Justice Center

In August, Andrus Intellectual Property Law sponsored the Milwaukee Bar Association’s golf outing benefiting The Milwaukee Justice Center (MJC), and the Andrus golf team (Joe Kuborn, Aaron Olejniczak, Peter Holsen and Kevin Spexarth) successfully defended their first place trophy in the golf tournament that day!