How Far Is Too Far? Unreasonable Claim Constructions Can Lead To Sanctions

Once a patent infringement lawsuit is filed, much time and effort is devoted by the parties and the court to arrive at the appropriate interpretation of the claims.  But how important is it to think about claim construction arguments before filing suit?  In Source Vagabond Systems Ltd., v. Hydrapak, Inc., the Federal Circuit recently reiterated that it is very important for counsel—and the patent owner—to ensure that all infringement arguments raised are based on claim construction positions that are reasonable and legally sound.  753 F.3d 1291, 1301 (Fed. Cir. 2014).  Failure do so, which can also amount to a failure to perform a reasonable prefiling investigation, can lead to a violation of Rule 11 that may result in sanctions including expenses and attorney fees.