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The United States Court of Appeals for the Federal Circuit recently granted en banc review in Lighting Ballast Control LLC v Philips Electronics North America Corp to decide whether to afford deference to a district court’s interpretation of patent claims, a step that has been heralded as potentially “lead[ing] to fundamental, far-reaching changes in patent law and patent litigation strategies.” Over the next few months, the parties, scores of amici, and commentators will spend reams of paper and untold amounts of money arguing whether claim construction—interpreting the short, numbered paragraphs at the end of the patent that define the patentee’s legal rights—should continue to be reviewed de novo or should be reviewed more deferentially. These efforts will be futile.

The Federal Circuit should be commended for addressing claim construction en banc for a fourth time in twenty years. Claim construction is the single most important event in any pa-tent case. It is a threshold question for virtually every other issue and is often case dispositive or, at least, case determinative. Scholars, judges, and practitioners criticize the Federal Circuit’s claim construction doctrine for creating unpredictability and uncertainty, high reversal rates, panel dependence, disincentives to settle, and increased litigation costs. These problems normally are ascribed to one or both of two causes: (1) institutional design, and primarily the Federal Circuit’s de novo review of claim construction; and (2) a deep and persistent methodological split over the relative effect on claim interpretation of the description of the invention in the patent specification and the “ordinary” meaning of claim language as derived from dictionaries, expert testimony, and other extrinsic sources.

It is not surprising that the Federal Circuit chose the first issue to review en banc. The standard of review for claim construction has been the more popular target for scholars and judges, with deferential review seen as a panacea that will cure all that ails the claim construction precedent. Yet, it was the wrong choice. Increased deference to district court claim constructions will do little or nothing to improve claim construction as long as the methodological split remains. And because the proper standard of review depends on the nature of the claim construction inquiry, the Federal Circuit cannot even effectively resolve this issue without first resolving the methodological schism.

The best path forward for the Federal Circuit is to dismiss the grant of en banc review in Lighting Ballast as improvidently granted and wait for an en banc petition that presents the methodological split. This will not happen. Instead, the Federal Circuit likely will adopt a more deferential standard of review, and practitioners and scholars will herald a new day of certainty and predictability in claim construction, only to find a few years from now that claim construction is just as unpredictable and uncertain, panel dependent, and prone to reversal as ever.