Judge Sleet’s recent order construing terms of patents in suit in this case between Bristol-Myers Squibb and Merck & Co. includes an interesting discussion of a limiting claim preamble. As Judge Sleet explained, the “parties’ dispute focuses primarily on whether a limitation should be incorporated in the terms that indicates the goal of the treatment” of metastasis of cancer cells using anti-PD-1 antibodies. “In the patents at issue, the claims explain what the method of treatment consists of, yet Merck would also have the court construe treatment to require the attempted result based upon the goal identified in the preamble: suppression of metastasis or proliferation of cancer cells. The court declines to limit the terms in this way.” Bristol-Myers Squibb Co., et al. v. Merck & Co., Inc., et al., C.A. No. 14-1131-GMS, order at 1 n.1 (D. Del. June 6, 2016).
Further, Merck argued that certain “wherein” clauses should be deemed limiting in that they require a particular effect, citing Griffin v. Bertina, 285 F.3d 1029 (Fed. Cir. 2002). Judge Sleet found, however, that although “that case did feature ‘wherein’ clauses like the patents at issue, the court is persuaded that in this case there will not be confusion about the reason for administering anti-PD-1 antibodies.” Id.