Digest of EMD Millipore Corp. et al. v. Allpure Techs., Inc. (Fed. Cir. Sept. 29, 2014) (precedential). On appeal from D. Mass. Before Prost, O’Malley, and Hughes.

Procedural Posture: Plaintiffs appealed district court’s grant of summary judgment that defendant did not literally infringe the asserted claims of the patent-in-suit nor infringe under the doctrine of equivalents. The CAFC affirmed.

  • Non-Infringement: The asserted patent relates to a device for introducing or withdrawing a sample from a container holding a fluid without contaminating the fluid. The CAFC held that the district court did not err by holding that disassembly of the accused transfer member could qualify as the claimed removal of the transfer member. The CAFC reasoned that since the accused device lacks the claimed seal when it is disassembled, it necessarily lacked the claimed “removable, replaceable transfer member.”
  • Prosecution History Estoppel: The CAFC held that it was unnecessary for the district court to perform a doctrine of equivalents analysis because prosecution history estoppel barred the plaintiff from making such an argument. During prosecution of the patent-in-suit, the applicant amended the claims to overcome prior art, thus, there was a presumption that prosecution history estoppel applied to the limitation at issue. Because the plaintiff failed to make any arguments to rebut the presumption that prosecution history estoppel applied (in the district court proceeding), the CAFC held that the plaintiff should have been barred from arguing that the accused device infringes the transfer member limitation under the doctrine of equivalents. However, the CAFC concluded that this error did not change the outcome of the case, because the district court still proceeded to grant summary judgment of non-infringement under the doctrine of equivalents on the merits.