Tag Archives: means-plus-function

Means-Plus-Function Claims in Patent Eligibility and Infringement Analyses

by Dennis Crouch

Means-plus-function claims have generally been disfavored because of the tendency of courts to  either (1) narrowly construe their scope when corresponding structure is detailed in the specification or (2) render them invalid as indefinite when the specification lacks sufficient corresponding structure. If Impact Engine’s petition is well received, there is a good chance that this historically popular claim style will see a revival. 

The Federal Circuit’s recent decision in Impact Engine v. Google has again raised the issue of over the proper treatment of MPF, this time regarding patent eligibility and infringement analyses. Appeal No. 22-2291  (Fed. Cir. July 3, 2024).  I had skipped a write-up of the non-precedential decision, but now Impact Engine has petitioned for en banc review, arguing that (more…)

USPTO ARP Panel Restores MPF Sanity, but Still Rejects Xencor’s Claims

by Dennis Crouch

In a new Appeals Review Panel (ARP), the USPTO has clarified the Office’s position on means plus function claims — explaining that the specification need not describe statutory equivalents to satisfy the written description requirement.  The outcome here shows value for the intentional use of means-plus-function limitations as a mechanism for expanding patent scope when genus claims are otherwise unavailable.

Still the court maintained the written description rejection on other grounds — finding that the broad preamble “method of treating a patient” to be limiting and not adequately supported by the specification.  Perhaps on remand the patentee will amend the preamble to instead claim a “means of treating a patient.”  (more…)

In re Xencor: USPTO’s Inaction Following Federal Circuit Remand

by Dennis Crouch

On January 23, 2024, the Federal Circuit granted the USPTO’s request for a remand in the case of In re Xencor, Inc. The appeal focused on two important issues concerning written description requirements for means-plus-function (MPF) and Jepson claims in the context of antibody patents. The USPTO had indicated that it wanted to reconsider its approach to these issues and convene its newly established Appeals Review Panel (ARP) to clarify its position. (ARP is the new POP). As part of its justification for remand, the Federal Circuit noted its expectation “that proceedings will be conducted expeditiously.”

However, more than two months after the remand order, there has been no visible progress in the case. The USPTO has not docketed the case with the ARP, and no public announcement has been made regarding the composition of the panel that will review the case. Furthermore, the prosecution history of the application in question (USPTO Application Number 16/803,690) does not reflect any updates or changes since the remand.

This lack of action is particularly concerning given the significance of the issues at stake. The PTAB previously made two controversial rulings that were on appeal: (1) that under 35 U.S.C. 112(f) equivalents require explicit written description support and (2) that non-limiting Jepson claim preambles also require such support, even if they do not limit claim scope.

Meanwhile, the USPTO did recently issue examination guidance on examining means-plus-function claim limitations under 112(f).  The troubling aspect of the memo, however, is that it does not provide any guidance on the Xencor enablement issue.

Citations:
[1] https://patentlyo.com/patent/2023/12/motion-remand-xencor.html
[2] https://patentlyo.com/patent/2024/01/important-antibody-description.html
[3] https://cafc.uscourts.gov/01-23-2024-23-2048-in-re-xencor-inc-order-23-2048-order-1-23-2024_2257719/