Jepson Claims

Jepson Claims

by Dennis Crouch

The chart above presents the powerful trend in the use of Jepson claim language in US patents over the years. It shows a clear decline in the percentage of patents that include Jepson claim language from 1980 to the present. In the early 1980s, around 8% of patents included at least one claim in Jepson format.  That figure has steadily decreased over the decades, falling to near 0% in recent years.

The Jepson format is a way of writing patent claims where the preamble states the known prior art, and the body specifies the improvements made over this prior art. Typically, the transition phrase will be in the form “wherein the improvement comprises” or “the improvement comprising.”

The patent regulations indicate that any “improvement” invention should be drafted in Jepson format.

Where the nature of the case admits, as in the case of an improvement, any independent claim should contain in the following order: (1) A preamble comprising a general description of all the elements or steps of the claimed combination which are conventional or known, (2) A phrase such as “wherein the improvement comprises,” and (3) Those elements, steps and/or relationships which constitute that portion of the claimed combination which the applicant considers as the new or improved portion.

Continue reading Jepson Claims at Patently-O.

Jepson Formats and Means Limitations Under More Fire

by Dennis Crouch

I have been following the pending Federal Circuit case of In re Xencor.  It is a quirky case involving both a Means-Plus-Function Claim and a Jepson claim.  In its decision, the PTAB went off the rails with its means-plus-function analysis.  In particular, the Board held that the MPF claim was invalid for lack of written description because the specification did not describe equivalents to the disclosed structure.

There is some logic to the decision. Let me try to explain: First, we know that written description doctrine requires a showing of possession of the full scope of the claims.   With MPF claims, we know that the statute requires a particular construction that includes both the structure described in the specification and “equivalents thereof.” 35 U.S.C. 112(f).  What we see here is that equivalents of the disclosed specification are within the literal scope of the claims — ergo, the written description must show possessions of those equivalents.

If you recall, a Jepson claim begins with a recitation something that is known or conventional, and then particularly claims the improvement — typically using a phrase such as “wherein the improvement comprises.”  The Jepson claim issue on appeal is the extent that the preamble portion of the claim must have been sufficiently supported by the original specification — even if the preamble carries no patentable weight for novelty or obviousness.

Continue reading Jepson Formats and Means Limitations Under More Fire at Patently-O.