Patently Obvious has a terrific rundown of the major themes in most of the amicus briefs filed last week in Phillips v. AWH, the Federal Circuit case on claim construction now up for decision on rehearing en banc. The court has a chance in this case to clear away an enormous amount of legal underbrush in the claim construction area, beginning with the ambiguity that currently surrounds the proper role of dictionaries — both lay and technical — in that process. Most of the briefs appear to be at least moderately hostile to reliance on dictionaries, particularly non-technical dictionaries. Polk Wagner (professor at UPenn) and Joe Miller (at Lewis & Clark) offer a not-entirely-contrary view, one that focuses on the certainty and predictability that peripheral claiming is supposed to provide and that is therefore more sympathetic than most of the briefs to the use of dictionary definitions.
Part of the divide here is related to an underlying conflict in the law (and perhaps on the Federal Circuit) regarding what claims and claim construction mean. Patent law reflects two only partly compatible concepts: In part, the patent claim represents the actual invention, and the process of claim construction is merely the process of divining what the invention truly is, as understood from the perspective of the imaginary Person of Ordinary Skill. Claims, in short, represent Truth. In part, the claim is a proxy — the first among many, in patent law — for the venerable balance between the interest of the inventor and the incentive that is his or her due, on the one hand, and the interest of the public and the progress of the art, on the other hand. Claims, in short, represent Policy.
Dictionary use may be easier to stomach so long as the Policy view predominates. The Truth view relies more directly on the PHOSITA concept itself, and it tolerates dictionaries mostly (and perhaps only) to the extent that they are part of the practice of the art (something that may be rare) or to the extent that they reflect it (as technical dictionaries may do).
I tend to cast my own lot with Truth. But Policy has had the upper hand at the Federal Circuit. Perhaps patent lawyers are headed for another showdown at the Supreme Court.