Means-Plus-Function Patent Claims: Anticipating the Outcome of Xencor

Course Details
- smart_display Format
On-Demand
- signal_cellular_alt Difficulty Level
Intermediate
- work Practice Area
Patent
- event Date
Monday, December 18, 2023
- schedule Time
1:00 p.m. ET./10:00 a.m. PT
- timer Program Length
90 minutes
-
This 90-minute webinar is eligible in most states for 1.5 CLE credits.
This CLE webinar will guide patent counsel on means-plus-function (MPF) antibody claims, particularly in light of the USPTO's adverse decision in Xencor. The panel will discuss the potential outcomes and the best practice options flowing therefrom, including best practices to avoid such an adverse decision in future antibody MPF claims.
Faculty

Mr. Irving has 47 years of experience in the field of IP law. His practice includes due diligence, patent prosecution, reissue and reexamination, patent interferences, and counseling, including prelitigation, Orange Book listings of patents covering FDA-approved drugs, and infringement and validity analysis in the chemical fields, as well as litigation. He has served as lead counsel in many patent interferences.

Ms. Brougher is a patent attorney who focuses on all aspects of services related to patents in the areas of biotechnology, pharmaceuticals and medical devices, including patentability opinions, due diligence, patent drafting, domestic and foreign patent prosecution, development and management of patent portfolios, and general client counseling during all phases of a product’s lifecycle, from concept to commercialization.
Her patent experience covers a variety of complex and innovative inventions involving small molecule drugs, biologics, cell-based technologies, compositions, drug formulations and drug delivery systems, immunotherapeutics, medical devices, diagnostic tests, nanotechnology, and immunology, particularly vaccines and antibodies. Ms. Brougher also has experience counseling clients on the Hatch-Waxman Act and is monitoring developments involving biosimilars under the Biologics Price Competition and Innovation Act.

Ms. O’Brien has more than 20 years of experience representing domestic and foreign clients of all sizes in patent procurement, litigation, and client counseling, with a particular emphasis on chemical, biochemical, and pharmaceutical technologies. Exemplary areas of her technical expertise include polymer chemistry; ceramics; glass; food chemistry; cosmetics; paper products; adhesives; and pharmaceutical products, including new chemical entities and formulations and novel solid forms, including polymorphs, cocrystals, and amorphous forms of compounds.
Description
Nearly all technological fields use MPF claiming. MPF claims, often perceived as narrow, can provide more protection for patent applicants than other claims. Following the Supreme Court's decision in Amgen (2023), many recommended using MPF claims for biopharma inventions. However, in the USPTO's decision in Xencor the Office is possibly closing the door on MPF claims for antibody patents.
There are two central issues: (1) Did Xencor sufficiently describe their antibody in the specification? (2) Assuming Xencor did, is Xencor's claim 9 unpatentable because Xencor did not, in the specification, set forth all possible equivalents to the disclosed antibody?
If (1), Xencor would lose, but the panel will explain how the decision would not be a body blow to MPF claims for antibodies. If (2), Xencor loses, the panel would then rue the future of MPF antibody claims, possibly with weeping, wailing, and gnashing of teeth and otherwise rail against such severe limitations being placed on antibody MPF claims, possibly rendering them worthless.
If the Federal Circuit, however, upholds (1) but not (2), then counsel should worry that failure to describe sufficiently the structure, materials, or acts corresponding to the claimed function under a 112(f) scenario may result in an unpatentable or invalid claim under 112(b). Also, even if (2) is not upheld, counsel will have to use best practices to clearly link the "means for" limitation to structures and/or acts in the specification.
As the panelists will explain, one might conclude that there is little possibility of the Federal Circuit sustaining point (2). Point (1), however, is not so clear. The finding of insufficient description of the antibody in the specification is most likely a question of fact, and it may be that the Federal Circuit will not overturn that factual finding of PTAB. The panelists will explain that if (2) is rejected, then counsel can save the MPF antibody claim by making sure at least one antibody designated as corresponding to the "means for" limitation is, incontrovertibly, sufficiently described.
Listen as our authoritative panel of patent attorneys examines MPF antibody claims, particularly in light of the USPTO's adverse decision on claim 9, and also in light of the Xencor brief and the amicus briefs that have been filed so far. The panel will predict how point (2) will be decided and what are the best practice options flowing therefrom. For educational purposes, the panel will assume arguendo that point (1) will be decided adversely to Xencor and then explain what best practices will be to avoid such an adverse decision in future antibody MPF claims.
Outline
- MPF antibody claims and the benefits of using them
- USPTO decision in Xencor
- Written description in Section 112(a) and Section 112(f)
- Definiteness of MPF antibody claims under Section 112(b)
- Amicus briefs
- What's the alternative if MPF is not available
- Best practices throughout
Benefits
The panel will review these and other noteworthy issues:
- What are the benefits and limitations of using MPF patent claims for antibody patents?
- What are the potential implications of the USPTO's decision in Xencor?
- What are the alternatives if MPF is not available?
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