The day has finally arrived where the full Federal Circuit will reconsider the precedent established in Cybor Corp. v. FAS Technologies Inc. In the 1998 case, the Federal Circuit established that claims construction rulings must be reviewed de novo on appeal and no deference is given to the district court. This might result in a new standard for claim construction review.

On March 15, the Federal Circuit granted an en banc rehearing of Lighting Ballast vs. Phillips Electronics & Universal Lighting Technologies and requested that the parties specifically brief the following:

[vision_pullquote style=”3″ align=”center”] Should Cybor be overruled and should the Federal Circuit afford any deference to any aspects of the district court’s claim construction and if so, which aspects should be afforded deference. [/vision_pullquote]

The Cybor decision has been both a blessing and a curse for all who practice in patent litigation since it has led to about 50% of the district court cases being reversed on appeal when the claims construction was at issue. This high reversal rate permits the losing party to continue the litigation as there is a 50-50 chance they will get another bite at the proverbial apple, and gives uncertainty to the prevailing party knowing that they could be easily reversed.

So why does the Federal Circuit want to review Cybor? Cybor established that claim construction is a question of law and therefore must be reviewed de novo. However, this is not always the case. Claim construction is not a simple proposition and the district court invests lots of time and energy in conducting Markman hearings where they review the facts relevant to the arguments made concerning claim meaning and assess the credibility of experts, inventors, and other witness who offer proof of in support of these underlying facts. These types of factual inquires are generally given deference in other circumstances but not so in claim construction.

The two most likely outcomes from the en banc review of Lighting Ballast is that Cybor is upheld or the court establishes a new standard in which factual issues related to claim construction are given deference. Although this new standard could be an improvement and incentivize the district courts to conduct a more thorough analysis of the claims since they will be less frequently overturned on appeal, it will also bring more uncertainty to the practice. The precedent established in Cybor was to avoid any ambiguity on what constitutes a factual inquiry and what constitutes a legal inquiry when evaluating claim language. Although claim construction is clearly not a pure question of law, it will be difficult to tease out what constitutes a question of fact when the two inquiries are so heavily intertwined.

Regardless of how the Lighting Ballast is decided, a review of Cybor has been long coming, and it appears to have finally been taken up en banc. A decision affecting the review of claims construction rulings will have wide ranging effects for all patent litigators and so we await this decision with bated breath.