Rule 11 contains a safe harbor, which allows a party to withdraw a claim within 21 days of receiving a sanctions motion. In this case, the plaintiff moved to voluntarily dismiss a design patent infringement claim within 21 days of receiving the sanctions motion. Rule 11 did not permit sanctions. The Defendants then sought sanctions under the court’s inherent authority, which the court denied. Sanctions under the court’s inherent authority are exceedingly rare and occur where the court believes that the party committed some egregious misconduct.
In sum, this is a classic example of the Rule 11 safe harbor in action.
Source: CAFFEINATE LABS, INC. v. VANTE INC., Dist. Court, D. Massachusetts 2017 – Google Scholar