Judge Linn on patent drafting

Not only do patent attorneys and agents find patent drafting incredibly frustrating, but judge seem to as well. As blogged by fedcirc.us, Judge Linn, a CAFC judge, grew frustrated during oral argument and stated the following:

“This is an interesting case...it's so typical of so many patent cases that are litigated and come up to this court. We have a term in the claim that's in dispute...it's not used anywhere in the written description. If that term was used in the written description, there wouldn't be this kind of debate. We're left hanging. Why patents are written this way I don't know. And then to compound the complexity, the application only has one embodiment, which of course puts into play this debate about '...is that just an embodiment or is that the invention'. We have both of these intriguing problems which are sort of self-inflicted by practicioners. I don't know why, but they're self-inflicted problems....”

Read the fedcirc.us analysis for a more thorough description of this case and the issues presented.

Patent scope limited by the summary

Normally, the scope of a patent is limited by its claims interpreted in light of the specification. The claims are a series of sentences that describe the invention. In most cases, they are written so that they broadly describe the invention thereby giving the inventor the broadest possible patent and the broadest possible protection.

Sometimes, however, judges ruling on patent cases will rely so heavily on the specification that they artificially limit the scope of the claims. A lawyer whose case is hurt by such an interpretation often presumes that the judge couldn't understand the claims (which can often be confusing) and instead relied on the specification - a much simpler portion of the patent.

This is a case where the judge relied on the summary of the invention to interpret the claims. The summary is a minor portion of a patent that is often informal and only included to make the patent easier to find in the various patent databases.

Whether or not the ruling was legitimate, it is a great reminder the specification should in no way limit the invention or call out necessary or preferred characteristics of an invention.