Claim construction is one of the most challenging tasks in the patent law game. We all struggle with it – prosecutors, examiners, litigators, judges. Lack of clarity and loyalty in the law aside, the task is a difficult one because, no matter how clear the meaning of a term is to you, it might have an entirely different meaning to someone else. This is often true irrespective of what the rest of the patent says about the meaning of the term, including the claim language, the specification, and the prosecution history.

Nothing illustrates this point better than a recent exchange between Judge Rader and counsel for the patent owner in Boston Scientific v. Cordis. Judge Rader asked about the meaning of a simple claim term – “implantable” – and the resulting exchange shows that a legal determination of the meaning of the term is anything but simple. “Implantable” is one of those terms you think you understand, until you really think about it…which is exactly what Judge Rader did. Ultimately, the meaning of the term was not dispositive in the case (it isn’t even mentioned in the opinion), but the oral argument should serve as a reminder to all of us about the complexities of claim language.

A transcript of the exchange appears below…but listening to the audio really underscores the point. You can download the mp3 from the court’s website (search for case number 08-1073) or listen to it on the PTP audio notes page for the case.

Judge Rader: “How can you have an implantable device before it’s sterilized? You wouldn’t implant something that’s going to kill a patient.”

Counsel (for patentee): “‘Implantable’ here, I think, clearly refers to the character, to the geometry, to the structure of the device…”

Judge Rader: “‘Implantable’ means capable of being implanted. I don’t think there’s any problem with that interpretation…You’re not going to implant an unsterile device, are you? An incomplete device….”

Counsel: “I can make two brief points on that Your Honor….”

Judge Rader (interrupting): “Get to my question: Implantable or not before it’s sterilized?”

Counsel: “It is physically implantable.”

Judge Rader: “How can it be? You’re abdicating implantation of a non-sterilized product.”

Counsel: “I’m certainly not abdicating anything. There’s no question that when a device like this is used in people it should be and must be sterilized.”

Judge Rader: “And can it be implanted before that?”

Counsel: “Yes it can be.”

Judge Lourie: “You mean physically, but it’s not medically ready.”

Counsel: “That would be correct, Your Honor.”