Chief Judge Gregory M. Sleet recently issued a claim-construction opinion notable for what it did not construe. On review of a magistrate judge’s recommendation, the Court rejected the defendants’ attempts to argue issues beyond the scope of the Markman proceeding:
“The defendants have also made a number of claim differentiation . . . and other invalidity arguments, though they couched these arguments as claim construction objections. Such validity arguments are not properly resolved at the claim construction stage.”
The Court’s decision stands as a warning to D. Del. practitioners: aggressive Markman tactics will not succeed in this district. (See also footnote 5 of the Court’s opinion.)