Professor Demchick's Blackboard

Dr. Demchick has been a college and university faculty member for many years. On these Blackboard Pages he does a little teaching. These pages are intended as general, introductory information. Compromises were made between including details in these pages and keeping the pages readable for a general audience. These pages are not intended as legal or other professional advice.

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CLAIMS

Claims are a key part of a patent. The claims state, in formal language, what is special and new about what is being patented.

With very limited exceptions, the patent holder can only prohibit others from making something which is within the scope of a claim. A few examples:

A claim which includes "…comprising eight spikes…" (probably) could not be used to prohibit someone from making the same sort of thing with six spikes.

A claim that includes "…a plastic liner…" (probably) could not be used to prohibit someone from making the same sort of thing with a glass liner.

A claim that includes "…including an indicator light…" (probably) could not be used to prohibit someone from making the same sort of thing with a buzzer instead of an indicator light.

So it might seem like a good idea to leave out all the details from a claim. However, it is important to write a claim so that it does not include anything that is prior art (e.g. something previously sold in the United States or something previously described in a publication in any country). A claim should not be allowed by the patent office if it is written in a way that includes any prior art. If the patent office does allow such a claim, the claim is likely to be invalidated if it is challenged in court. Writing a patent claim which is limited enough, but not too much, is tricky.

Inventors who represent themselves often end up with problematic claims. Often the inventor ends up writing a "picture claim." A picture claim is one that gives a very detailed description of the invention (it "paints a picture" of the invention with words). A claim like that is likely to be approved by the patent office. However, the patent protection is likely to be very weak. The claim (probably) cannot be used to prohibit someone from making something very much like the invention if they change one of the details in the claim.

The patent office has specific rules about the mechanics of how claims are to be written.

A patent may include more than one claim. A patent application with more than twenty claims (or more than three independent claims) requires payment of an extra fee.

Provisional patent applications are not required to have claims. However, some caution should be exercised. Failure to specifically point out and distinctly claim the subject matter which the applicant regards as the invention in the U.S. Provisional Patent Application could have a negative impact on patent rights in other countries. Therefore, in my practice I include wording to protect foreign patent rights.

There has been a United States patent system almost as long as there has been the United States. However, the patent system has undergone many changes. Even early patent applications included a description of the invention. Without claims, there was a great deal of guesswork about what aspects of an invention were at the heart of that invention.